106A ANNUAL MEETING ABSTRACTS presentation of this information within electronic medical records. Thus, any provider in a variety of tissues, including thyroid in two-thirds. The purpose of this study is to reviewing a patient record will have immediate access to detailed and current knowledge investigate whether there is correlation between the thyroid pathology and the PTEN on that patient’s particular leukemia or lymphoma. mutation in a specific exon. Design: All thyroid lesions from patients with known PTEN mutation were retrieved 479 Virtual Educational Portal for the Digital Slide Image Repository from the Departments of Pathology of Brigham and Women’s Hospital and Children’s at a Large Academic Multi-Institutional Center Hospital. Specimen photographs, histopathology, clinical and molecular findings were reviewed. SJ Sirintrapun, RA Cecil, T Harper, M Castine, L Drogowski, J Duboy, J Ho, JL Fine, L Results: Eleven cases of PHTS [Cowden syndrome (CS) 7 cases; Bannayan-Riley- Anthony, AV Parwani, DM Jukic. University of Pittsburgh Medical Center, Pittsburgh, Ruvalcaba syndrome (BRRS) 4 cases] in 7 females and 4 males were studied. The PA; University of Pittsburgh, Pittsburgh, PA. mean age at diagnosis of the thyroid lesion was 27 years (range 11-68). Each thyroid Background: At the University of Pittsburgh Medical Center, because of geographic had multiple pathologic findings including: multiple adenomatous nodules (MAN, n=7 logistics, the educational use of glass slides has been difficult. Capturing glass slides cases), with focal clear cell changes (n=3 cases), papillary carcinoma (PTC, n=4 cases), digitally became the solution to providing availability. The premise is for educational follicular carcinoma (FC, n=3 cases), and multiple follicular adenomas (FA, n=2 cases). slides to be viewable at any computer and at any institution associated with UPMC. Eight cases (73%) showed marked lymphocytic thyroiditis, and one also had C cell In order to unite the entire collection of educational digital slides from the different hyperplasia. Correlation of the 7 germline mutations and pathologic findings revealed: sites and servers, we developed a web-based “virtual” portal which provides the main exon 5 (cases 1, 2, 8) FC and MAN, multifocal PTC and nodular hyperplasia, and MAN, gateway by which our entire digital slide image repository can be easily accessed and respectively; exon 6 (cases 5, 10, 11) PTC, multiple FAs and PTC microcarcinoma, and utilized by even the most amateur of users. FC, respectively. The case with mutation in exon 8 (case 7) revealed FC and MAN. Design: The educational teaching slides are scanned and captured on the Trestle Digital Conclusions: Both benign and malignant multicentric and distinct thyroid lesions Slide Maker (DSM) or Aperio ScanScope system and stored on a Stored Area Network were observed in PHTS; no morphologic differences were seen between those in CS (SAN) server. Digital viewers include the proprietary ImageScope and Trestle’s Java and BRRS. Although, there was no correlation between specific germline mutations viewer. The database used to provide context is Microsoft SQL Server. The web (exons) and morphologic findings, the presence of MAN in a background of lymphocytic based portal is created on a SUNONE platform via a Cold Fusion MX Enterprise thyroiditis is distinct and characteristic of this syndrome. Middleware. Results: Since early 2004, over 5000 digital slide images have been scanned and Age Gender Diagnosis Diagnosis PTEN gene mutation Thyroid Diagnosis collected, with our web based portal only recently providing centralized access. Medical (yrs) students, residents, fellows, or attendings no longer need to go to specific physical M BRSS 24 R130Q; 389 G>a at codon 130, Exon 5 FC, MAN, LT locations to obtain glass slides. Training is facilitated with the web-based viewers. When F CS 38 Y180X, Exon 5 PTC, NH, LT using the Trestle viewer, history and case notes can be annotated on the slide simulating F CS 34 No MAN, PTCmicro, LT a question and answer format. Key histologic features can be marked aiding in training F CS 64 NA MAN F CS 22 c.609_611delTCCinsATAAAT, Exon 6 PTC,MAN, LT an inexperienced eye. Distribution of unknown slides is performed without the need F CS 48 NA PTC, MAN for multiple recuts, loss of material, or transportation hindrances. M CS 12 c.968dupA, Exon 8 FC, MAN, LT Conclusions: With our digital slide images, the entire slide is captured digitally and M BRRS 23 c.389G>A, Exon 5 MAN, LT therefore simulates the reality of evaluating a glass slide. Skills such as screening, F CS 68 NA PTC, FAs finding the essential areas of interest, and knowing how to navigate through a slide F BRRS 11 c.512-513InsA, Exon 6 FAs, PTCmicro M BRRS 13 c499_505del7ACTATTC, Exon 6 FC, LT can be practiced over the internet. With static images, because the area of interests are immediately shown, these key intangible skills are lost in the learning process. Our centralized web portal provides an invaluable tool and further enhances our commitment 482 Familial Non-Medullary Thyroid Carcinoma: Morphologic to education in pathology. Patterns Indicating an Inherited Trait J Dotto, W Faquin, P Sadow, H Kozakewich, V Nosé. Brigham and Women’s Hospital, Boston, MA; Massachusetts General Hospital, Boston, MA; Children’s Hospital, Endocrine Boston, MA. Background: Non-medullary thyroid carcinoma (NMTC) is quite common, although only 5% are familial (FNMTC). Clinically, FNMTC can be divided into two major 480 A Comprehensive Survey of Kinase Pathway Mutations in groups, syndromes characterized primarily by non-thyroid tumors [PTEN Hamartoma Poorly Differentiated Thyroid Carcinomas Using High-Throughput Mass Tumor Syndrome (PHTS) and Familial Adenomatous Polyposis (FAP)] and those Spectrometry-Based Genotyping characterized primarily by FNMTC (FPTC). DA Chitale, M Ryder, JCR Filho, J Knauff, M Ladanyi, J Fagin, R Ghossein. Henry Ford Design: Thyroid cases of FNMTC were retrieved from our files, 1999 to 2007. Specimen Hospital, Detroit, MI; Memorial Sloan Kettering Cancer Center, New York, NY. photographs, stained slides, medical records, and molecular findings were reviewed. Background: Poorly differentiated thyroid carcinoma (PDTC) represents the major We correlated thyroid pathology with molecular genetic findings. cause of death from thyroid carcinomas. Aim: 1) To perform a comprehensive screen Results: We identified 22 cases of FNMTC (11 PHTS, 8 FAP, 3 Multiple FNMTC). for known thyroid cancer-associated kinase pathway mutations in PDTC using a high PHTS (7 females and 4 males) had mean age of detection of a thyroid lesion at 27 years throughput genotyping technique. 2) To correlate the mutation status with known (range 11-68). The most common findings were multiple adenomatous nodules (MAN, clinicopathologic parameters. 7 cases) with clear cell changes (3 cases), followed by papillary carcinoma (PTC, 4 Design: PDTC were defined on the basis of high mitotic activity and/or tumor necrosis. cases), follicular carcinoma (FC, 3 cases), multiple follicular adenomas (FA, 2 cases), DNA was extracted from 43 paraffin-embedded tissue blocks from 36 patients. The and C cell hyperplasia (1 case). Eight cases (73%) showed lymphocytic thyroiditis. Seven samples were then genotyped using a highly multiplexed Sequenom mass spectrometry- patients had confirmed PTEN germline mutations. Eight FAP patients (all females), based mutation assay that screened for 11 mutations in BRAF, 8 in NRAS, 7 in HRAS had a mean age at diagnosis of thyroid carcinoma of 34 years (range 18-53). Five were and 11 in PIK3CA. Mutations were confirmed by direct sequencing. diagnosed as PTC, cribriform-morular variant (CM-PTC), 2 as PTC, follicular variant, Results: Overall, mutations were found in 14 (39%) of the 36 samples tested. BRAF and one was classical PTC. Mean tumor size was 1.3 cm; seven cases were multifocal V600E mutations were identifed in 7 (19.4%) of 36 patients with the following with multiple encapsulated nodules with marked sclerosis. In CM-PTC, the cribriform phenotypes (3 tall cell, 2 non-tall cell papillary, 1 follicular, 1 with a mixture of follicular, pattern predominated over the morular component, with no lymphocytic thyroiditis. oncocytic and papillary). NRAS mutations at codon 61 were found in 6 (17%) of the Six patients had APC germline mutations. From the preponderance of FNMTC (FPTC) 36 cases (including 3 non-tall cell papillary, 2 follicular, 1 with a mixture follicular, cases, one of three (mean age 56 years) with multifocal PTC had an abnormal tumor oncocytic and papillary). Only 1 patient had HRAS mutation at codon 61, in a PDTC karyotype with a breakpoint in 19p13.2 suggestive a TCO gene mutation. Tumor size with a follicular phenotype. Mutation at codon 1047 of PIK3CA was detected in one ranged from 0.8 to 2.5 cm. Two tumors were multifocal with extrathyroidal extension, tumor with a papillary phenotype. One patient had concomitant BRAF V600E and NRAS vascular invasion and lymph node metastasis. Lymphocytic thyroiditis was uniformly mutations, both confirmed by direct sequencing; this tumor showed a mixture of Hurthle, present. Follow up (24 to 186 months) showed no tumor recurrence. follicular and nuclear papillary areas. BRAF mutation was present in all PDTC with Conclusions: Multifocal involvement of the thyroid was a common feature in all tall cell morphology (3 of 3, 100%) and in only 4 (12%) of the 33 remaining patients FNMTC inherited tumor syndromes. Lymphocytic thyroiditis was present in both PHTS (p=0.005). The mortality rate from PDTC was 67%. There was no significant correlation and multicentric FPTC. Characteristic morphologic findings, such as CM-PTC, MAN, between the mutation status and other clinicopathologic parameters such as extra-thyroid and multicentric FPTC, should alert pathologists to notify clinicians of the possibility extension (ETE) and survival. The presence of ETE and extra-thyroid vascular invasion of an inherited trait, such as FAP, PHTS, or FPTC. correlated with death of disease (p=0.004, 0.017 respectively). Conclusions: 1) Kinase pathway mutations are present in a substantial number (39%) of patients with PDTC.2) Although extra-thyroid extension rather than mutation was 483 Immunohistochemical Expression of Notch Molecules in Human a predictor of outcome, a significant number of PDTC may be amenable to targeted Pituitary Adenomas: Their Relationship with Subtypes of Adenomas therapy based on the presence of certain kinase pathway mutations. N Egashira, S Takekoshi, M Takei, A Teramoto, RY Osamura. Tokai University School of Medicine, Isehara, Kanagawa, Japan; Nippon Medical School, Tokyo, Japan. Background: Notch signaling molecules (ligands and receptors) are type I 481 Thyroid Pathology in PTEN Hamartoma Tumor Syndrome (PHTS): transmembranous proteins that regulate the cell differentiation and proliferation through A Clinocopathologic and Molecular Genetic Analysis of a Distinctive cell-cell interactions. Under the activation by Notch ligands, the Notch intracellular Entity domain (NICD) is cleaved and translocated into the nucleus. So far, in human pituitary J Dotto, H Kozakewich, V Nosé. Brigham and Women’s Hospital, Boston, MA; gland, it has been reported that NOTCH3 mRNA was expressed in clinically non- Children’s Hospital, Boston, MA. functioning adenomas. NIH array database indicated that, in human pituitary gland, four Background: PHTS is a complex disorder caused by germline inactivating mutations of Notch receptors (NTCH1, 2, 3, 4) and five Notch ligands (DLL1, 3, 4, Jagged1, 2) are the PTEN tumor suppressor gene. Carriers develop both benign and malignant tumors identified. This study is aimed at to elucidate the relationship between the expressions ANNUAL MEETING ABSTRACTS 107A of Notch molecules and subtypes of human pituitary adenomas, in order to clarify the 485 Molecular Classification and Prognostication of Adrenocortical role of Notch signaling. Tumors by Gene Expression Profiling Design: Tissues from total 66 cases of pituitary adenomas (19 GH producing adenomas: TJ Giordano, R Kuick, DG Thomas, M Vinco, D Sanders, J Bauersfeld, T Else, P Gauger, GHomas, 9 PRLomas, 7 ACTHomas, 1 TSHomas, 14 gonadotropin (Gn)-omas, 12 null G Doherty, G Hammer. University of Michigan, Ann Arbor, MI. cell adenomas) were subjected to the following immunohistochemical studies. The Background: Our understanding of the pathobiology of adrenocortical carcinoma tissues were fixed in formalin and embedded in paraffin. All antibodies against Notch (ACC) has improved considerably over the last decade. Yet many unanswered questions molecules (NOTCH1, NOTCH3, DLL1) were supplied by Santa Cruz (CA, USA). remain. For instance, can ACC be divided into molecular subtypes and, if so, what is ABC method was used. the underlying basis for those subtypes and do they possess clinical significance. To Results: NOTCH 1 was positive in the nuclei (nuclear translocation) in GHomas,PRLomas address these and other questions, we performed a whole genome gene expression study and TSHomas. JAGGED1 and JAGGED2 were positive in GHomas and PRLomas. Only of a large cohort of adrenocortical tissues and analyzed the data in conjunction with JAGGED2 was positive in TSHomas. ACTHomas showed the presence of NOTCH1 pertinent clinicopathologic data. and/or NOTCH3. Only DLL1 was noted in ACTHomas. In Gn-omas and null cell Design: Using Affymetrix Human Genome U133 Plus 2.0 oligonucleotide arrays adenomas, NOTCH1 and NOTCH3 as well as all three ligands were positive. The containing over 54,000 probe sets, transcriptional profiles were generated for 10 normal ligands were localized on the cell membrane of the tumor cells. adrenal cortices (NCs), 22 adrenocortical adenomas (ACAs), and 35 ACCs using RNA Conclusions: Our data suggest that NOTCH1 and NOTCH3 signaling may play some derived from frozen human tissues. The pathology of each case was reviewed and patient roles in the functional differentiation particularly for cellular subtypes GH-PRL-TSH outcome data was obtained. cells in human pituitary adenomas, i.e. (1) NOTCH3 signal transduction may be Results: The overall morphological classification of adrenocortical tumors was specifically functional in GHomas, (2) Active NOTCH1 may function in PRLomas recapitulated using principal components analysis of the entire data set. The NC and and JAGGED2 activated Notch signaling in TSHomas. ACAs cohorts showed relatively little intra-group variation, whereas the ACC cohort revealed significant diversity indicative of a high level of gene expression variation. Further cluster analyses of the ACC cohort revealed 2 distinct subtypes that reflected tumor proliferation, as measured by mitotic activity, and aneuploidy. These ACC clusters were associated with differences in patient survival (p=.0167). A highly robust (false discovery rate of 0.004%) list of 2,875 differentially expressed genes in ACC compared to NC and ACA combined was generated and used in pathway enrichment analysis to assign biological significance of the gene expression profile. Conclusions: Gene expression profiles can accurately classify adrenal cortical tumors and divide the ACCs into subtypes with prognostic significance. In addition, expression profiles can provide vital insight into the pathobiology of ACC that will be required for the development of novel targeted therapies.

486 Automated Quantitative Analysis (AQUA) of Claudin 1 as a Diagnostic Marker of Papillary Thyroid Carcinoma TJ Giordano, D Sanders, R Koenig, Y Nikiforov, DG Thomas. University of Michigan, Ann Arbor, MI; University of Pittsburgh, Pittsburgh, PA. Background: The diagnosis of thyroid tumors, especially follicular patterned tumors, is often problematic with significant interobserver variation. Thus, novel markers are needed to assist in the evaluation of these nodules. Using a DNA-microarray based approach to marker discovery, claudin 1 was previously shown to be expressed in papillary thyroid carcinoma (PTC) at high levels compared to other thyroid tumors. Claudin 1 immunohistochemistry was also previously shown to support this finding using semi-quantitative manual scoring. Here, we used automated quantitative analysis (AQUA) to explore claudin 1 expression in a cohort of PTCs and follicular adenomas (FAs). Design: Tissue arrays that contained 97 FAs, 109 primary PTCs and 54 metastatic PTCs 484 Retroperitoneal Paraganglioma, 70 Cases: Attempt to Histologically were constructed with duplicate tissue cores and used for fluorescent staining. These Predict Malignant Behavior cases represented the full morphologic spectrum of these tumors and were independent JC Fanburg-Smith, A Auerbach, CS Heffess. Armed Forces Institute of Pathology, of the cases used to generate the DNA microarray data. Automated quantitative analysis Washington, DC. (AQUA) was performed with the PM-2000 instrument (HistoRX, New Haven, CT) using Background: Retroperitoneal pargangliomas (RP) are rare. Most malignant RP require the following detection design: DAPI for nuclei, anti-cytokeratin 18 antibody for the metastasis for diagnosis. Predictors of behavior are controversial. tumor mask, and anti-claudin 1 antibody for the marker antibody. A 1:200 dilution of Design: 200 cases coded as RP were reviewed. Inclusion required adequate material, anti-claudin 1 antibody was used. definite non-adrenal retroperitoneal location, and correct diagnosis, based on morphology Results: AQUA scores were generated for the tissue cores and analyzed using an and IHC for chromogranin and sustentacular cells for S100. Malignant(M) was defined unpaired T-test with Welch correction. Expression of claudin 1 in the primary PTC by known metastases. Histologically malignant (HM) required angiolymphatic space cohort was significantly higher than in the FA cohort (676 +/- 435 vs. 238 +/- 184, p < invasion, central tumor necrosis of large spindle cell nests, and/or high mitotic activity 0.001). Likewise, claudin 1 expression in the metastatic PTC cohort was significantly (>20/10 hpf). Histologically atypical (HA) showed capsular invasion and large spindle higher than in the FA cohort (512 +/- 251 vs. 238 +/- 184, p < 0.001). cell nests. Functional (F) required production of catecholamines; patients often had Conclusions: These results demonstrate that claudin 1 is expressed at significantly headache, nausea/vomiting, palpitations. Multiple paragangliomas (MP) had >1 lesion higher levels in PTC compared to FA and provide additional support for the use of in a sympathetic distribution; pigmented paraganglioma (PP) melanin pigment. claudin 1 as a diagnostic immunohistochemical marker of PTC. Results: 70 cases included 8 M, 13 HM (2 with pseudopapillary pattern), 5 HA, 3 MP, and 41 paraganglioma (3 PP, 27 F, 1 Carney Triad with gastrointestinal stromal tumor). 487 BRAF Mutational Analysis in Papillary Carcinomas with Mixed 5M had metastases to regional lymph node and 3 to distant bone, 5 were non-F, sizes Follicular and Papillary Growth Patterns ranged 6-13, median 11, cm. All but one (8 male, HA with capsular invasion and 2 M Jakubowski, JL Hunt. Cleveland Clinic, Cleveland, OH. mits/10 hpf) met our HM criteria. The 11 HM cases had >2 mits/10 hpf and uniformity Background: Current literature suggests that up to 60% of papillary carcinomas have of tumor cells, 7 were non-F, sizes ranged 6-19, median 10, cm. HA (5-19 cm) were mutations in the BRAF gene. However, follicular variant of papillary carcinoma has a all non-F, the 3 MP (3-8 cm) all F. Histologically benign (HB) had small Zellballen much lower frequency of mutation. Tumors with mixed patterns of growth, including clusters of ironically pleomorphic with multinucleated cells, pseudonuclear inclusions, distinctive area of follicular and papillary growth, have not been well studied for the no cytoplasmic hyaline globules, and absence to 1 mit/10 hpf. Brown fat was observed presence of the BRAF gene mutation. outside of capsule in F tumors. All had pericapsular hypertrophic nerve with ganglion Design: Cases of papillary carcinoma were identified with well defined conventional cells. Overall 39 F: 31 M, ages ranged 8-84, median 47, only 6 patients under 19 years. papillary growth pattern, alongside other areas with follicular growth pattern. The TNM Neither age nor gender correlated with histologic classification. Preoperative MIBG stage was obtained, along with demographic information. The different growth pattern scan reliably predicted MP. Occasionally organs or vessels required removal at surgery; areas were separately microdissected and DNA was extracted from the resulting tissue rarely non-F tumors caused blood pressure elevations during surgical manipulation. fragments. PCR was performed for an amplicon in BRAF exon 15 that includes the Preliminarily, 1M with bone metastasis died of disease at 3 years; all HB or MP were mutation site. Cycle sequencing was performed using the BigDye Terminator kit and alive up to 21 years. analysis was performed on an ABI automated sequencer (Applied Biosystems). The Conclusions: RP has pericapsular hypertrophic nerve and lacks cytoplasmic globules. forward and reverse sequences were analzyed for point mutations. FRP have perilesional brown fat. Lack of F, angiolymphatic space invasion, central Results: DNA extraction and PCR amplification was successful in all cases. 73% of necrosis of large spindle cell nests, and increased mitoses may predict malignant the tumors were positive for the BRAF mutation. In comparing the follicular and the behavior. While the final outcome of MRP is yet to be determined, 11% are M and papillary growth patterned areas, the BRAF mutation was concordant in all cases. Two 30% HM. cases had an additional separate focus of microscopic follicular variant of papillary carcinomas. Both of these were negative for the BRAF mutation. Conclusions: Papillary carcinomas of the thyroid with papillary growth and areas of follicular growth have a high frequency of BRAF mutations. The BRAF mutational profile is identical in the follicular areas and in the conventional papillary growth 108A ANNUAL MEETING ABSTRACTS areas. These molecular data support the common diagnostic decision that a tumor with angiogenesis and angiectasis. Anti-VEGF antibody (bevacizumab) is known to be as any amount of conventional papillary growth should be designated as a conventional an antibody for therapeutic agents designed to inhibit tumor angiogenesis. As most papillary carcinoma, regardless of the presence of follicular growth pattern areas. endocrine tumors are rich in vascularity, anti-VEGF can be expected to exert anti-tumor effects. The aim of this study is to elucidate the inhibitory effects of anti-VEGF antibody 488 Parathyroid Carcinoma Can Be Differentiated from Benign on rat PRLoma induced by estrogen. Parathyroid Lesions Using HRPT2 and Galectin-3 Immunohistochmical Design: Female F344 rats of 7 weeks of age were injected (i.m.) with 0 (Control), Stains, a Tissue Microarray Study 3000 µg/kg/week of estradiol (E2-treated) for 10 weeks, and the half of E2 treated rats received 5 mg/kg of anti-VEGF antibody (Anti-human and murine VEGF monoclonal E Khanafshar, GG Fernandez-Ranvier, E Kebebew, QY Duh, D Tacha, OH Clark. antibody; Ava, G6-31, kindly supplied by Genentech Inc.) intravenously at 2 days after University of California, San Francisco, San Francisco, CA; Biocare Medical, Concord, each E2 injection (Ava-treated) for 3 weeks. The animals were sacrificed at 13-week CA. of E2 dosage, their pituitary glands were removed and weighed. Samples of each Background: Parathyroid carcinoma, atypical parathyroid adenoma, and group were examined histopathologically. Formalin-fixed paraffin embedded tissues parathyromatosis can be differentiated relatively easily from typical parathyroid were used for immnohistochemistry. PRL cell proliferation was detected by Ki-67 adenomas, but distinguishing them from each other by histological features only could immunohistostaining, and the number of apoptotic bodies was determined by TUNEL be difficult and challenging. method in sections of the E2-induced PRLoma. Design: Total 69 specimen from 60 patients with parathyroid carcinoma, atypical Results: Pituitary weights in the G6-31-treated group were decreased compare to that adenoma, parathyromatosis, parathyroid adenoma, and parathyroid hyperplasia were of E2-treated group. On the other hand, histopathological examination revealed that the selected (18 carcinomas, 3 atypical adenomas, 16 cases of parathyromatosis, 18 number of distended blood vessels in the anterior lobe was diminished by Ava treatment parathyroid adenomas and 14 cases of parathyroid hyperplasia). Tissue cores with compare to E2-treated group. The Ava treatment also lowered proliferation of PRL cells a diameter of 1 mm were prepared from the paraffin blocks and placed in a tissue evaluated by the numbers of Ki-67-positive cells and increased the number of apoptotic microarray (TMA) recipient paraffin block. Slides were prepared from the block bodies determined by TUNEL method. and stained by Galactin-3 and HRPT2 (Parafibromin) according to the manufacturer Conclusions: These results suggest that this experimental design of E2-inducled rat instructions. The slides read by a pathologist, and a surgeon. They all scored as positive PRLomas will serve as a model to study the therapeutic effects of anti-VEGF antibody or negative. on vascular rich endocrine tumors. Results: Loss of expression of HRPT2 was seen in 6 out of 18 (33%) carcinoma specimen but not on any of the other four categories. Strong Galectin-3 expression was seen in 16 out of 17 (94%) carcinomas. It was negative or weakly positive in other four categories (see table 1). Results of HRPT2 and Galectin-3 stains in Parathyroid Lesions HRPT2 HRPT2 Galectin3 Galectin-3 Positive Negative Positive Negative Carcinoma 12/18 6/18 (33%) 16/17 (94%) 1/17 Atypical adenoma 2/2 0/2 2/2 0/2 Parathyromatosis 16/16 0/16 4/16 12/16 Adenoma 18/18 0/18 1/18 17/18 Hyperplasia 14/14 0/14 2/14 12/14 68 samples scored for HRPT2 and 67 for Galectin-3 Conclusions: Loss of expression of HRPT2 along with diffuse strong positivity for Galactin-3 can be seen only in patients with parathyroid carcinoma. These two stains can be used for differentiating challenging cases, when the morphological features fall short of diagnosis of carcinoma.

489 Immunohistochemical Expression of Parafibromin Is of Limited Value in Distinguishing Parathyroid Carcinoma from Adenoma S Mangray, KC Kurek, E Sabo, RA DeLellis. Rhode Island Hospital, Providence, RI; Children’s Hospital, Boston, Boston, MA. Background: The HRPT2 gene is responsible for the hyperparathyroidism-jaw 491 Gene Expression Profiling Unravels Molecular Mechanisms of tumor (HPT-JT) syndrome and has also been shown to be involved in parathyroid Progression in Primary Pancreatic Endocrine Tumors and Matched Liver carcinogenesis. Loss of nuclear expression (diffusely absent or weak staining) of Metastases parafibromin (PFib), the protein product of theHRPT2 gene, by immunohistochemistry A Nasir, DT Chen, GC Bloom, NA Nasir, NM Gardner, J Strosberg, P Hodul, SA (IHC) has been reported to be useful in distinguishing parathyroid carcinoma (PTHCa) Enkemann, BA Centeno, D Coppola, MP Malafa, TJ Yeatman, LK Kvols. H. Lee Moffitt from sporadic adenomas (PTHAd) (Am J Surg Pathol 2006;30:1140-1149). We Cancer Center and Research Institute, University of South Florida, Tampa, FL. investigated PFib expression in a spectrum of parathyroid lesions to determine whether Background: Pancreatic endocrine tumors/carcinomas (PETs/PECAs) are rare, yet it was reproducible and, moreover, whether PFib could be used to classify cases of so clinically challenging neoplasms. Development of metastases results in a significant called “atypical adenomas” (APTHAd) as PTHCa. drop in patient survival. However, the biology of progression of these tumors is largely Design: Archival cases of normal parathyroid glands, hyperplastic glands, sporadic unknown. adenomas (PTHAd), PTHCa and APTHAd were studied. Cases of APTHAd were Design: In order to gain insight into the molecular mechanisms of progression of PETs/ characterized by the presence of a thick capsule, fibrous bands, mitotic activity, nuclear PECAs, we selected A) 6 pairs (N=12) of metastatic primary (MP)-PECAs and matched pleomorphism or necrosis, but lacking features for an unequivocal diagnosis of PTHCa: liver metastases (MLMs) from 6 patients (mean age 59 years, 3/3 M/F) and B) 5 non- 1. presence of definitive invasion through the capsule into soft tissue or adjacent thyroid; metastatic (NM)-PETS from 5 other patients (mean age 66 years, 3/2 M/F). Methods: 2. vascular space or perineural invasion; or 3. metastases. IHC was performed on paraffin Frozen tissues from 17 PETs/PECAs and 2 normal pancreas were macrodissected to embedded 4 micron sections using a commercially available mouse monoclonal antiPFib achieve 80-98% of tumor enrichment. The extracted RNA was run on Affymetrix U133 antibody (SC-33638, Santa Cruz, CA). Staining patterns were categorized into 3 groups plus 2.0 gene chip. RMA and t-test were used to identify differentially expressed genes as defined in the study above: 1. diffusely strongly positive if >95% of nuclei showed between A) MP-PECAs and NMP-PETs, and B) MP-PECAs and their MLMs. Candidate staining; 2. negative staining when > 99% of cells completely lacked nuclear staining; gene selection was based on lower p-values, high fold change, gene function/class and and 3. weak staining for all other patterns. extensive literature search. Results: There was diffuse strong staining in all 24 normal glands, 31 hyperplastic Results: Gene list A. Fifty four transcripts were differentially expressed between MP- glands and 30 sporadic adenomas studied. Five of 13 (38.4%) carcinomas showed diffuse PECAs and NMP-PETs, using p-value <0.01 and fold-change values >1.2, >1.5, >2, strong positive staining while 3/13 (23.1%) had absent staining and in the remaining 5 >4 (54, 25, 10 and 1 gene respectively). Gene list B. 222 transcripts were differentially cases (38.5%) there was weak staining (median percentage of positively stained nuclei expressed between MLMs and MP-PECAs at p-value <0.01 and fold-change values 55%, range 20-70%). In the APTHAd group 14/18 (77.9%) cases demonstrated diffuse >1.2/>1.5/>2/>4/>8 (222-29-5-1 and 1 gene respectively). Insulin-receptor, SMURF1, strong staining, 1/18 (5.5%) absent staining and the remaining 3 cases weak staining RNF43 and AKR1C2 were among the upregulated, while glucagon, RASSF5, RERG, (positive staining of up to 30% of nuclei). RUNX1T1, ST14 and PDGFRL, were among the downregulated genes in list A. Conclusions: Loss of parafibromin expression in PTHCa was found to occur at a Similarly, osteonectin and FGFR2 were among the upregulated, while APRIN, SSTR1, substantially lower rate than reported (61.6% vs 91%) and PFib expression in APTHAd CHGA, NRCAM, RASSF3, ST18 and SMAD1 were among the downregulated genes was more in keeping with that of PTHAd. Additionally, the wide range of positive nuclear in list B. Based on their functions, all of these genes were selected as “candidate staining in IHC category 3 limits the use of PFib in routine clinical practice. progression genes” for validation on independent test sets of archival primary-PETs/ metastatic-PECAs. 490 Animal Model for Bevacizumab (Anti-VEGF Antibody) Therapy Conclusions: Based on gene expression profiling of unique tumor sets, we have for Human Endocrine Tumors: Targeted Inhibitory Effect of Anti-VEGF identified an expression profile that would be predictive of progression of PETs and Antibody on the Growth and Angiogenesis of Estrogen-Induced Pituitary PECAs. The most promising of the validated genes will be used to develop a clinically Prolactinoma in Fischer 344 Rats useful ‘progression assay’ for these neoplasms. K Miyajima, S Takekoshi, T Miyakoshi, J Ito, H Kajiya, N Egashira, RY Osamura. Tokai University School of Medicine, Isehara, Kanagawa, Japan. Background: We have demonstrated the high level of vascular endothelial growth factor (VEGF) expression in estrogen-induced rat prolactinoma (PRLoma) with marked ANNUAL MEETING ABSTRACTS 109A

492 Absence of BRAF Mutation in HBME1 and CK19 Positive Atypical microarrays and conventional whole sections. TTF-2 and Pax8 were also applied on Cell Clusters in Hashimoto’s Thyroiditis: Evidence Against Preneoplastic 147 cases of lung carcinomas (114 adenocarcinomas, 29 squamous cell carcinomas, Change and 4 large cell carcinomas) as well as normal tissue and common malignant tumors MR Nasr, S Mukhopadhyay, S Zhang, A-LA Katzenstein. State University of New York from other organs/sites. The extent of staining was graded as 1+, 1-25%; 2+, 25-50%; Upstate Medical University, Syracuse, NY. 3+, 50-75%; 4+, >75%. Background: An association between Hashimoto’s thyroiditis (HT) and papillary Results: All three markers were seen in all PCAs, FAs, FCAs, and ICAs in a diffuse thyroid carcinoma (PTC) has been known for decades. We undertook this study to fashion and strong intensity, whereas their expressions in MCAs were variable. Pax8 was investigate the expression of immunohistochemical markers of PTC in follicular expressed in 79% of ACAs to a variable extent, whereas TTF-1 and TTF-2 were seen epithelium of HT to identify potential precursor lesions not recognizable in routine only in 18 and 7% of ACAs, respectively. TTF-2 was negative in all other neoplastic stains. We further tested for BRAF mutation in these lesions, since this mutation is and non-neoplastic tissues including those of the lung. Pax-8 was expressed in renal present in most cases of PTC but not in HT. tubules and lymphoid follicles as well as clear cell renal carcinoma, nephroblastoma, Design: Formalin-fixed, paraffin-embedded tissue from 40 cases of uncomplicated seminoma, ovarian serous carcinoma and diffuse large B cell lymphoma, but not in HT and 19 cases of HT containing papillary microcarcinomas (PMC) elsewhere was normal tissue and carcinomas of the lung. stained with antibodies to HBME1, fibronectin1 (FN1), and CK19. BRAF mutation Conclusions: Pax8 is a useful marker for the diagnosis of anaplastic thyroid carcinoma, was analyzed by both Colorimetric Mutector Assay and an allele-specific PCR on particularly when the differential diagnosis includes pulmonary carcinoma. In DNA extracted after microdissection of small foci with positive HBME1 and CK19 differentiated thyroid neoplasms, no significant difference in expression was seen immunoreactivity. Six PMC’s, 5 PTC’s, and 4 uncomplicated HT cases were additionally between all three transcription factors. studied by this technique. Results: Scattered small (<1mm) foci of epithelial cells showed positivity for HBME1 495 Reduced Expression of the let-7 microRNAs in Human Pituitary in 4 of 40 (10%) uncomplicated HT cases and in 8 of 19 (42%) HT cases containing Adenomas Is Associated with Pituitary Tumorigenesis through Up- PMC elsewhere. The HBME1-positive foci were CK19 positive in all 12 cases, although Regulating HMGA2 Expression extensive staining was also present elsewhere in 56/59 (95%) cases. Eight of 12 HBME-1 ZR Qian, T Sano, YF Yuan, SL Asa, S Yamada, E Kudo. Institute of Health Biosciences, positive foci showed staining for FN1. Examination of H and E-stained sections in the The University of Tokushima Graduate School, Tokushima, Japan; University of areas of HBME1 positivity showed occasional cells with nuclear grooves and nuclear Toronto, Toronto, ON, Canada; Toranomon Hospital, Tokyo, Japan. overlapping and/or nuclear clearing. The findings were not, however, considered Background: The molecular pathway leading to pituitary tumorigenesis is one of the sufficient to diagnose PMC. BRAF mutation was found in 4 of 5 PTC’s and 2 of 6 challenges of the endocrine oncology. Recently, miRNAs are a recently discovered PMC, but not in any of the small foci of HBME1 positivity. class of small nucleic acids that negatively regulate gene expression. Aberrant miRNAs Conclusions: The finding of HBME1 positive cell clusters showing some morphologic expression can contribute to tumorigenesis. To understand the role of miRNAs in features of PTC in HT, and their occurrence with increased frequency in cases with pituitary tumorigenesis we profiled the miRNAs in normal pituitary tissue and in PMC elsewhere initially suggested that they might represent premalignant/dysplastic pituitary adenomas and try to detect the clinical link between miRNAs and target gene foci. The absence of BRAF mutation, however, in all 12 cases is evidence against in pituitary adenomas. a preneoplastic change, and suggests that the HBME1 positivity is a non-specific Design: We profile the expression of miRNAs in normal human pituitary tissue and reaction. Caution should be exercised in interpreting positive HBME1 staining in HT. pituitary adenomas using 2 different independent and complementary methods, miRNA The presence of extensive nonspecific staining for CK19 in HT epithelium precludes cloning and real-time RT-PCR. The most widely used programs have been employed to its utility as a marker of malignancy in this setting. identify target genes of miRNAs. Over-expression of HMGA2 has been demonstrated by immunohistochemistry. The link between let-7 and HMGA2 has been analysised. 493 Diagnostic Utility of MicroRNA Profiling in Thyroid Fine Needle Results: At first, using Effective Size-based miRNA Cloning Technology and Northern Aspiration (FNA) Samples blot, we identified about 60 miRNAs from a normal human pituitary gland and several MN Nikiforova, JE Dipaola, DL Steward, YE Nikiforov. University of Pittsburgh, pituitary adenomas. We found the frequency of let-7 family in normal tissues is higher Pittsburgh, PA; University of Cincinnati, Cincinnati, OH. than these in tumors. Then using real-time RT-PCR, we detected the expression of let-7 Background: MicroRNAs (miRNAs) are small non-coding RNA molecules that in 3 normal pituitary tissues and 55 pituitary adenomas. The reduced expression of let-7 function as negative regulators of gene expression. Specific miRNAs are found to was found in 33% (18 of 55) tumors and potentially involved in tumor procession in be differentially expressed in thyroid tumors as compared to normal thyroid tissue. human pituitary adenomas. Next we searched for putative let-7 targets through several In this study, we determined the diagnostic utility of miRNA profiling of thyroid fine the most widely used programs. We found that HMGA2 may be the most possible needle aspiration (FNA) samples and its possible role in the preoperative assessment target of let-7. Thus we examined HMGA2 expression in 90 pituitary adenomas. The of thyroid nodules. over-expression of HMGA2 was observed in 35 of 90 (39%) pituitary adenomas and Design: Sixty-two consecutive thyroid FNA samples with known cytological diagnosis, significantly related with tumor progression. Interestingly, in 55 pituitary adenomas, surgical pathology diagnosis (14 patients) and clinical follow-up of 1-3 years (48 HMGA2 over-expression was significantly related to low-expression of let-7. Thus, patients) were used for the analysis. All FNA specimens were collected into nucleic we provided clinical evidence of the link between let-7 and HMGA2. Such relation acid preservative solution (Roche). Expression of 7 miRNAs most highly upregulated between let-7 and HMGA2 also was confirmed in tumor cell lines. in thyroid tumors based on our previous studies of surgical samples, i.e. miR-187, Conclusions: Losing let-7 repression induced HMGA2 up-regulated should be important miR-221, miR-222, miR-146b, miR-155, miR-224, and miR-197, was detected using mechanism in pituitary tumorigenesis and progression. RT-PCR MicroRNA Assays on ABI 7500 (Applied Biosystems). miRNA expression was calculated relative to hyperplastic nodules (HNs) after normalization to endogenous 496 Histopathologic Characterization of Radioactive Iodine Refractory control. (RAIR) FDG-PET Positive Thyroid Carcinoma (TC) Results: Among those patients who underwent surgery, 8 had malignant tumors (7 M Rivera, RM Tuttle, R Ghossein. Memorial Sloan-Kettering Cancer Center, NY. papillary carcinomas and 1 follicular oncocytic carcinoma) and 6 HNs. All of the 8 Background: RAIR PET positive carcinomas represent the major cause of deaths from malignant cases revealed >2 fold overexpression of 1-6 miRNAs tested. Among them, TC and are therefore the main focus of novel targeted therapies. Until now, the histology 7 papillary carcinomas showed at least 3 upregulated miRNAs, whereas one follicular of FDG-PET positive RAIR metastatic thyroid carcinoma has not been described. carcinoma demonstrated upregulation of miR-221 only. Five out of 6 HNs showed Design: Metastatic tissue from RAIR PET positive patients was selected for histologic downregulation of all 7 miRNAs and one HN showed upregulation of miR-197 only. The examination from 1987-2005. The biopsied metastatic site corresponded to a FDG- other 48 samples from patients who did not undergo surgery revealed no upregulation PET positive lesion sampled within 2 years of the PET scan. Microscopic examination of any of these miRNAs in 46 cases and upregulation of one miRNA in 2 cases. was performed on the metastatic deposit and the available primary tumors. Poorly Conclusions: Our results indicate that freshly collected thyroid FNA samples can be differentiated thyroid carcinomas (PD) were defined on the basis of high mitotic activity used for detection of miRNA expression. MiR-187, miR-221, miR-222, miR-146b, miR- (> 5 mitosis/10 high power fields) and/or tumor necrosis. Other types of carcinomas 224 and miR-155 were found to be highly overexpressed in FNA samples derived from were defined by conventional criteria. malignant tumors and were not overexpressed in HNs, indicating that miRNA profiling Results: 70 patients satisfied the selection criteria, of which 43 had primary tumors for may be used for refining the preoperative diagnosis of thyroid nodules. Further studies review. The cohort consisted of 33 females and 37 males with ages ranging from 22-85 are needed to fully validate the diagnostic use of miRNAs in thyroid FNA samples. years (median:55.5). The primary and metastatic tumors were classified as anaplastic (ANA), PD, Hurthle cell (HC), tall cell (TCV) and well differentiated papillary thyroid 494 Diagnostic Utility of Pax8 in Thyroid Epithelial Tumors with Special carcinoma (PTC) (frequencies listed in Table). ANA, PD, TCV and widely invasive HCC Emphasis on Anaplastic Carcinoma represented 77.1% of the metastatic thyroid carcinomas and 76.7% of the primaries. Of D Nonaka, Y Tang, L Chiriboga, M Rivera, R Ghossein. New York University School of the primary tumors classified as PTC, 70% progressed to more aggressive histotypes in Medicine, New York, NY; Memorial Sloan-Kettering Cancer Center, New York, NY. the metastasis (met). 73% of the cases classified as PD in the metastasis died of disease Background: Thyroid-specific transcription factors, Pax-8, TTF-1, and TTF-2, are with a median survival of 7 years. However the overall survival (OS) was not stratified crucial for thyroid organogenesis and differentiation. Compared with TTF-1 the other by the histology of the met in this group. Tumor necrosis in the primary was able to two markers have been scarcely investigated in surgical pathology. The goal of this study predict OS in this group of patients by Kaplan-Meier analysis (p=0.02). 71% of the is to evaluate the expression of these markers in thyroid tumors along the full spectrum PD primaries were initially classified by the primary pathologist as well differentiated of differentiation, with special emphasis on anaplastic carcinomas (ACAs). Sensitivity (WD) tumors based on the presence of a papillary and/or follicular architecture or the and specificity of these markers in thyroid tumors were assessed by evaluating their presence of PTC nuclear features. expression in non-thyroid tissues including lung carcinomas. ANA PD HC TCV PTC Design: A total of 94 cases of thyroid neoplasms were studied: 17 papillary carcinomas Metastasis 1.4%(n=1) 47.1%(n=33) 8.6%(n=6) 20.0%(n=14) 22.9%(n=16) (PCAs); 18 follicular adenomas (FAs); 16 follicular carcinomas (FCAs); 7 poorly Primary 0 48.8%(n=21) 7.0%(n=3) 20.9%(n=9) 23.3%(n=10) differentiated (insular) carcinomas (ICAs); 28 ACAs; and 8 medullary carcinomas Conclusions: 1) The majority of patients with RAI refractory PET positive metastases (MCAs). Immunostains for Pax8, TTF-1, and TTF-2 were performed using tissue have a histologically aggressive tumor in the primary, however WD RAIR metastatic 110A ANNUAL MEETING ABSTRACTS disease is observable. 2) PD is under recognized in many cases if defined by architectural thyroid (NT), papillary thyroid carcinoma (PTC), follicular adenoma (FA), hyperplastic and nuclear features alone. 3) The presence of tumor necrosis is a strong predictor of nodules (HYP) and follicular carcinoma (FC). RNA from 40 ex vivo FNA (HYP, FA and aggressive behavior even within this group of clinically aggressive tumors. PTC) was also analyzed. Small RNA U6 was used as the endogenous control. Results: miRNA were successfully extracted from all paraffin-embedded tissues and all 497 Increased Insulin-Like Growth Factor II and IGF1 Receptor Alpha but one FNA samples, with paraffin sections yielding better miRNA quality. Preliminary Expression in Pancreatic Islets of Adult Patients with Post-Gastric Bypass analysis of 6 miRNAs (miR-146a, 146b, 155, 187, 221 and 222) in 10 PTC and 10 Surgery Nesidioblastosis FA identified significant overexpression of miR-146b, 221, and 222 in PTC (P<0.05), but not miR-146a, 155 or 187. The expression of these first 3 miRNAs was examined KM Rumilla, LA Erickson, FJ Service, GB Thompson, RV Lloyd. Mayo Clinic, in an expanded sample of 5 NT, 11 HYP, 24 FA, 27 classical PTC (PTCC), 5 PTC Rochester, MN. follicular variant (PTCFV), and 2 FC. Results showed miR-146b to be most consistently Background: Hypoglycemia secondary to nesidioblastosis with hypertrophied islets overexpressed in both PTCC and PTCFV, with 28 of 32 cases having expression levels and enlarged nuclei of islet cells is rare in adults. The pathogenesis of this condition higher than all 42 cases in the other groups (p<0.001 for all pair-wise comparisons). NT, is unknown. HYP, FA and FC all showed similar expression at a lower level. miR-221 and miR-222 Design: We analyzed 24 cases of patients with post-gastric bypass nesidioblastosis and also showed higher expression in PTC than in FA, HYP and NT (p<0.001), but with 8 cases of adult patients with noninsulinoma pancreatogenous hypoglycemia syndrome substantial overlaps between PTC and non-PTC groups. Strong correlation between (NIPHS) with nesidioblastosis by immunohistochemistry. Antibodies to insulin-like miR-221 and miR-222 expression was seen (r=0.963), confirming previous finding that growth factor (IGF)1, IGF2, IGF1 receptor alpha (IGF1R alpha), epidermal growth they are coordinately regulated. When applied to 40 ex vivo FNA samples (10 HYP, factor receptor (EGFR), transforming growth factor beta 1 and 2 (TGF beta 1 and 2) 10FA, 10 PTCC, 10 PTCFV), only miR-146b and miR222 persisted as distinguishing and transforming growth factor receptor beta type III (TFG beta RIII) were used with markers between PTC and non-PTC cases (p<0.001 and p=0.021 respectively), while the avidin-biotin peroxidase method. Immunoreactivity was graded from 0 (negative) to miR221 was not significantly different (p=0.105). 3+ (strong). A control group of 44 surgically resected pancreatic tissues from 44 patients Conclusions: Formalin-fixed tissues contained well-preserved miRNA suitable for with benign exocrine tumors was also studied. Morphological features associated with expression analysis. miR-146b, miR-221 and miR-222 are overexpressed in PTC, but nesidioblastosis including ductuloinsular complexes and vascular ectasia within islets not in follicular adenoma or hyperplasia. Diagnostically, miR-146b is most promising were also studied. and may potentially be an adjunct marker for diagnosing PTC in both FNA and surgical Results: There was increased IGF2 expression in pancreatic tissues from both sets of pathology specimens. nesidioblastosis patients compared to controls (p=0.02 for each group). IGF1R alpha expression was also significantly higher in patients with nesidioblastosis compared to body mass index-matched control patients. IGF1, EGFR, TGF beta 1, TGF beta 500 CEACAM1 Expression in Pancreatic Endocrine Tumors 2 and TGF beta RIII were not significantly different in the nesidioblastosis patients S Serra, SL Asa, R Chetty. University Healt Network, University of Toronto, Toronto, compared to controls. Ectatic vessels with a peliosis-type pattern was detected more ON, Canada. frequently in both nesidioblastosis groups compared to controls (p=0.002). After insulin Background: Carcinoembryonic Antigen-related Cell Adhesion Molecule1 immunostaining the ductuloinsular complexes were not significantly different between (CEACAM1) is a transmembrane protein belonging to the CEA immunoglobulin patients with nesidioblastosis and controls. superfamily with a role in maintenance of tissue architecture, and is expressed by Conclusions: Nesidioblastosis in post gastric bypass patients and in adults with NIPHS epithelial, endothelial and most hematopoietic cells. CEACAM1 is a putative tumor is characterized by increased IGF2, IGF1R alpha, and increased ectatic islet cell vessels suppressor; it is overexpressed in non-small cell lung cancer. The aim of this study was with a peliosis-type pattern suggesting that various growth factors may contribute to to examine the expression of CEACAM1 in pancreatic endocrine tumors (PETs) and the development of this disorder in adults. correlate with clinical-pathological parameters. Design: Fifty seven cases were examined for tumor size, necrosis, local invasion (LI) 498 Loss of O6-Methyl-Guanine-Methyl-Transferase (MGMT) and lymphovascular invasion (LVI), lymph node (LNM) and liver metastasis (LM). Immunoreactivity Is a Predictor of Poor Survival in Pancreatic Endocrine The mitotic count, expressed per 10/HPF and MIB-1 index were assessed. Tumors were Tumors (PET) graded according to the WHO. A tissue microarray was constructed and stained with an extensive panel of endocrine markers as well as CEACAM1. The localization of the AM Schmitt, M Anlauf, S Schmid, T Rudolph, Y Jonkers, EJ Speel, H Moch, P Komminoth, stain and intensity (weak, moderate and strong) were recorded. A Perren. University Hospital Zurich, Zurich, Switzerland; City Hospital Triemli, Results: Twenty-seven were males and 30 females, age range: 23 to 80 years (mean 49.8 Zurich, Switzerland; TUM, Munich, Germany; University of Maastricht, Maastricht, years), tumors ranged from 0.8 to 11cm (mean 3.6 cm), 6 had MEN1 syndrome and 1 Netherlands; University of Kiel, Kiel, Germany. von Hippel-Lindau disease. Sixteen tumors were LI, 12 showed LVI, 15 had LNM and Background: MGMT is an important enzyme of DNA repair. Inactivation of MGMT can 6 had LM. In normal pancreatic islets, CEACAM1 immunoreactivity was weak and lead to chromosomal instability. From our previous comparative genome hybridization cytoplasmic. In PETs, CEACAM1 showed cytoplasmic staining of variable intensity (CGH) studies we know that chromosomal instability is a significant feature in advanced and, less frequently, membrane staining. CEACAM1 was negative in 20 cases (35.1%). and especially in malignant PET. A recent study has shown that MGMT promoter Of these, 1 PET was LI, 4 showed LVI but none had LNM or LM. Of the 14 cases with methylation is detectable in a subset of PET. The aim of the present study was to test a weak cytoplasmic staining, 1 was LI, 3 had LVI, 4 LNM and 3 LM. Of the 8 cases whether MGMT promoter methylation will lead to loss of MGMT protein expression with moderate staining, 1 was LI, 3 had LNM and 1 LM. Fourteen cases were strongly in PET. Furthermore, loss of MGMT expression might be a cause of chromosomal positive: 4 showed LVI, 4 LNM and 2 LM. 90% of the CEACAM1 negative cases had instability. Loss of MGMT function is thought to be a predictor of response to alkylating a MIB-1 index ≤ 2%, whereas 92.9% of CEACAM1 positive cases had a MIB-1 index agents such as temozolamide. >2% (p=0.01). 85% of the CEACAM1 negative PETs had a mitotic count ≤2/10HPF, Design: Methylation sensitive PCR (MSP) of the MGMT promoter was performed using whereas 75% of the positive PETs had a mitotic cont >2/10HPF. Insulin was positive fresh frozen tissue of 48 PET. A tissue micro array of 126 PET was immunostained for in 63.6% of the CEACAM1 negative PETs (p=0.01) and VIP positive PETs were all MGMT and scored semiquantatively. Survival data were available from 80/126 (63.5%) CEACAM1+ (p=0.01). patients. Conventional and array-CGH data were available of 42 tumors. Kaplan-Meier Conclusions: Angioinvasion, higher mitotic count and MIB-1 index, lymph node curves were used for survival analysis. Methylation status, immunohistochemistry and involvement and liver metastasis were significantly higher in CEACAM1+ PETs. data on chromosomal instability were correlated using cross tabulation. Insulin producing-PETs were significantly more frequent in CEACAM1-, whereas Results: 41/126 (33%) of the examined PET showed a complete loss of MGMT protein all VIP positive tumors were CEACAM1+. Benign and PETs of uncertain behavior expression. Concordance of MGMT protein expression and promoter methylation status were more frequently CEACAM1- and low-grade malignant cases were CEACAM1+ was identified in 19/37 tumors (51.4%). Furthermore there was no correlation between (p=0.001). MGMT status and chromosomal instability. Only loss of MGMT protein expression correlated significantly with a shortened disease free survival (p=0.0054). Conclusions: Loss of MGMT protein expression is an adverse prognostic marker in 501 FGFR3 and FGFR4 Mutational Analyses in Thyroid Carcinoma sporadic PET. Immunohistochemistry correlates better with prognosis than MGMT S Serra, S Cheng, S Ezzat, SL Asa. University of Toronto, Toronto, Canada. gene promoter methylation. This indicates that MGMT promoter methylation is Background: Four families of Fibroblast Growth Factor Receptors (FGFRs) are neither the only mechanism for loss of protein expression nor by itself sufficient encoded by 4 genes. Activating mutations of FGFR3 are frequent in multiple myeloma for MGMT silencing. MGMT immunohistochemistry might therefore be the better and transitional cell carcinoma of bladder. In addition, an FGFR4 polymorphism, Gly/ predictor of MGMT function and therefore also of response to alkylating agents such Arg388, has been associated with poor outcome in oropharyngeal, breast, colorectal as temozolamide. and prostate cancers. We examined thyroid carcinomas of follicular cell derivation for FGFR3 mutations and FGFR4 polymorphic Gly/Arg388 genotype status and their 499 microRNA Analysis as a Potential Diagnostic Tool for Papillary relationships to clinical and pathological parameters. Thyroid Carcinoma Design: We studied 115 thyroid cancers that were sub-classified with WHO criteria. Size, focality, vascular invasion (VI), extrathyroidal extension (ETE), lymph node metastasis T Scognamiglio, N Kitabayashi, XK Zhou, TJ Fahey III, Y-T Chen. Weill Cornell Medical (LNM) and distant metastasis and relevant clinical data were recorded. Representative College, New York, NY. tumor and normal tissue were microdissected for DNA extraction. Exons 7, 10 of fgfr3 Background: MicroRNAs (miRNAs) are non-coding RNAs that have been shown and exon 16 of fgfr4 were amplified and sequenced. Exon 9 offgfr4 was PCR amplified to regulate the expression of mRNAs, and miRNA microarray analysis has found and RFLP digested with BstN1 to distinguish three FGFR4 genotypes: wild type (WT), consistently altered expression of several miRNA species in thyroid tumors, suggesting heterozygous Gly 388 (Het) and homozygous Gly 388 (Hoz). their roles in thyroid carcinogenesis. Whether this differential expression can be used Results: There were 80 females (69.6%) and 35 males; 58 (50.4%) tumors were classic as a diagnostic tool in surgical pathology and fine needle aspirate (FNA) specimens papillary carcinomas (PTC), 35 (30.4%) oncocytic and follicular variant (FV) PTC, 8 was explored. (7%) tall cell (TC) PTC and 12 (10%) poorly differentiated (PDC) or anaplastic (ATC) Design: The expression of selected miRNA was evaluated by quantitative RT-PCR, carcinomas. Sixty four (55.7%) were unifocal, 50 (43.5%) had LNM, 32 (27.8%) using RNA extracted from 74 formalin-fixed paraffin-embedded sections from normal ETE and 20 (17.4%) had VI. Exons 7 and 10 of fgfr3 and exon 16 of fgfr4 had no ANNUAL MEETING ABSTRACTS 111A mutations. Germline FGFR4Gly 388 was identified in 68 patients with features shown Conclusions: The inactivating mutations and/or allelic loss of HRPT2 gene may not play in Table1. a major role of parathyroid carcinogenesis in secondary HPT due to CKD. The cancer FGFR4 Gly/Arg388 WT [N (%)] Het [N (%)] Hoz [N (%)] Significance* development may be associated with a heterogeneous genetic disorder in these cases. N 47 (40.9) 57 (49.6) 11 (9.6) Gender F 29 (36.3) 45 (56 2) 6 (7.5) P = 0.054 M 18(51.4) 12(34.3) 5914.3) 504 The Incidence of Occult Papillary Thyroid Carcinomas in Type Classic 18 (31) 35 (60.3) 5 (8.6) P = 0.05 Patients with Benign Thyroid Nodules Oncocytic / FV 17 (48.6) 15 (42.9) 3 (8.6) MD Williams, JW Suliburk, GA Staerkel, NL Busaidy, JE Lee, GL Clayman, DB TC 4 (50) 4 (50) 0 Evans, ND Perrier. M.D. Anderson Cancer Center, Houston, TX; Univeristy of Texas, PDC / ATC 7 (58.3) 2 (16.7) 3 (25) Houston, TX. LNM Yes 24 (48) 22 (44) 4 (8) NS No 21 (36.8) 30 (52.6) 6 (10) Background: Surgical excision is often required for classification of thyroid nodules Focality Uni 25 (39.1) 37 (57.8) 2 (3.1) P = 0.011 identified as follicular lesions by fine needle aspiration (FNA). Although the majority Multi 20 (45.5) 16 (36.4) 8 (18.2) of these lesions will be benign clinically occult papillary thyroid carcinoma (oPTC ETE Yes 9 (28.1) 20 (62.5) 3 (9.4) NS <1.0 cm) may be detected in the background thyroid. To account for the incidence and No 35 (46.7) 33 (44) 7 (9.3) characteristics of oPTC in patients with benign follicular thyroid nodules, we reviewed VI Yes 9 (45) 11 (55) 0 NS our experience at M.D. Anderson Cancer Center. NS: Non significant. *Chi-Square test. Design: All patients diagnosed with a follicular lesion by FNA at a single institution Conclusions: FGFR3 and FGFR4 intragenic mutations are not present in thyroid cancer. from 1990-2007 formed the cohort for this study. Patients with FNAs suspicious for FGFR4 Gly388 Het was more frequently associated with PTC and with aggressive papillary thyroid carcinoma were excluded as were cases where the FNA evaluated behavior (LNM and ETE). These data highlight the potential impact of mono-allelic thyroid nodule was malignant on the resection specimen. The histologic characteristics loss of FGFR4 function in thyroid cancer behavior. of the oPTCs and the associated follicular lesions were assessed. Results: 354 (57.8%) of the 612 patients with a follicular lesion by FNA underwent 502 Rapid In Situ Hybridization for miRNA-221 and miRNA-222 in surgery. 315 (89%) were benign thyroid nodules: follicular adenomas and adenomatous Formalin-Fixed Paraffin-Embedded Papillary Thyroid Carcinoma nodules. oPTC was identified in 17 (5.4%) of the surgical specimens with benign nodules MT Tetzlaff, ZB Baloch, VA LiVolsi, EE Furth, KT Montone. Hospital for the University (8 total thyroidectomies, 9 lobectomies). oPTC were associated with the following of Pennsylvania, Philadelphia, PA. lesions: 11 (64.7%) adenomas, five (29.4%) nodular goiters; and one (5.9%) case of Background: MicroRNAs (miRNA) are abundant non-coding RNAs that repress target Hashimoto’s thyroiditis. oPTCs ranged from 0.1 to 0.6 cm, five (29.4%) were multifocal gene expression. The altered expression of miRNAs has been correlated with a variety of of which one had extrathyroidal extension and one had lymph node metastases. Patients benign and malignant conditions. Recently, we described miRNA profiling in papillary were 41 to 71 years old (mean 56 years); 9 females and 8 males. 10 of 17 (58.8%) had thyroid carcinomas (Tetzlaff et al., 2007) and found that miRNA-221 and miRNA-222 a secondary cancer history; 2 had concomitant hyperparathyroidism. Two patients with are up-regulated in papillary thyroid carcinoma (PTC) compared to multinodular goiter multifocal oPTC received radioactive iodine. None of the patients underwent further (MNG). Our goal was to develop an in situ hybridization assay to confirm the presence surgery and there were no recurrences (mean follow-up 44 months (3-162 months)). and cellular location of these miRNAs in formalin-fixed, paraffin-embedded (FFPE) Conclusions: Our findings show 1) oPTC may co-exsist in thyroids with benign sections of thyroid carcinoma. follicular lesions, 2) features including multicentricity, extrathyroidal extension and Design: The in situ hybridization was performed on FFPE cases of PTC which had been lymph node metastases may be identified, 3) pathologic examination of the background shown to highly express miRNA- 221 and miRNA-222 by miRNA profiling. Cases of thyroid for oPTC is recommended, and 4) longer follow-up is required to determine the MNG were used as controls. Briefly, in situ hybridization was performed using manual clinical significance of oPTC in this population. capillary action technology on the MicroProbe staining system The FFPE tissues were deparaffinized, cleared, rehydated and then digested with 2.5 mg/ml of pepsin for 3 505 Methylation Screening of Thyroid Cell Lines and Tissues o minutes at 105 C. The miRNA linked nucleic acid (LNA) probes were labeled with MD Williams, JP Issa, C Lu, GL Clayman, AK El-Naggar. M.D. Anderson Cancer digoxigenin on the 3’ end (Exiqon), diluted to 20 nM/ml in a formamide-free probe Center, Houston, TX. o diluent and applied to the slides. The tissues and probe were heated to 105 C for 4 Background: Loss of vital tumor suppressor genes function through molecular minutes, allowed to cool at room temperature for 1 minute and hybridized for 2 hours alterations or epigenetic changes including methylation contribute to tumorigenesis o at 58 C. Following hybridization, the tissues were washed three times with 2XSSC in many solid tumors. Methylation of CpG rich islands in promoter regions and initial o for 5 minutes at 58 C. The tissues were incubated with anti-digoxigenin antibody exons leads to transcription suppression of involved genes. Identification of genes and conjugated to alkaline phophatase (1:200) for 1 hour at room temperature followed by pathways altered through methylation may aid in diagnosing follicular lesions and chromogen development with NBT/BCIP for 2 hours. The total procedure time was provide target regions for therapy. We screened cell lines and thyroid tissues for the approximately 5½ hours. frequency of methylation events surrounding cell cycle genes that may be involved Results: In papillary thyroid carcinoma, miRNA-221 has a faint cytoplasmic but strong in tumorigenesis. nuclear staining reminiscent of nucleolar localization. In contrast, miRNA-222 has Design: Ten thyroid cell lines (seven anaplastic carcinomas, two papillary carcinomas, predominantly cytoplasmic staining in these same cases. In situ hybridization of the and one follicular carcinoma), 33 tumor tissues comprised of five anaplastic, ten papillary probes on 2 cases of multinodular goiter showed only faint nuclear and cytoplasmic carcinomas, nine follicular carcinomas, and nine follicular adenomas and 37 normal staining. Other miRNAs exhibit a similarly non-specific faint staining pattern in both thyroid tissue, 33 of which were paired specimens, formed the materials for this study. goiter and papillary thyroid carcinoma. Methylation specific polymerase chain reaction was used to evaluate methylation in Conclusions: A rapid in situ hybridization procedure confirms the presence and cellular PTEN, TSH receptor (TSHR), thyroid transcription factor (TTF-1), p16, p14 and E- localization of miRNA-221 and miRNA-222 in FFPE papillary thyroid carcinomas. This cadherin. Methylation PCR product >10% compared to the unmethylated product was technique holds promise for characterizing and localizing miRNAs in FFPE tissues in considered methylated. the general surgical pathology laboratory. Results: Tumor cell lines regardless of diagnose showed near global hypermethylation of the PTEN, TSHR, and p16 genes, partial methylation for TTF-1 and ECAD and absence 503 Expression of Parafibromin in Parathyroid Carcinoma in of methylation in the p14 gene. The majority of tumor tissues were unmethylated with Advanced Secondary Hyperparathyroidism Patients Due to Chronic Kidney no methylation detected in the PTEN and p16 genes and rare methylation in E-cadherin Disease as noted below. Two paired normal samples had low methylation in TTF-1 with no T Tsuzuki, Y Tominaga, S Matsuoka, N Uno, T Sato, S Shimabukuro, N Goto, T Nagasaka, methylation in any tumor tissues. Low to moderate methylation in TSHR occured in K Uchida, N Maeda. Nagoya Daini Red Cross Hospital, Nagoya, Japan. most normal and tumor tissues, with higher methylation of TSHR in 2 of 10 papillary Background: Recently somatic inactivating mutations in HRPT2 have been reported carcinomas. Anaplastic carcinomas and matched normal tissues were methylated in p14 in the majority of sporadic parathyroid carcinoma in primary hyperparathyroidism (3 of 5) with methylation also noted in one of these tumors for E-cadherin. (HPT). Parafibromin, which is a tumor suppressor protein encoded by HRPT2, and Conclusions: Our study shows 1) Cell lines have high levels of gene methylation and loss of nuclear expression of parafibromin, was found in approximately 70% of the may not reflect patterns present in tumor tissues, which may limit their utility in screening carcinoma. In secondary HPT due to chronic kidney disease (CKD), parathyroid new CpG regions. 2) Global low to moderate levels of methylation of the TSHR carcinoma is very rare and whether HRPT2 plays a role in the carcinogenesis in these gene suggest a possible innate regulatory mechanism or higher gene susceptibility to cases is not investigated. We evaluated the expression of parafibromin in hemodialysis methylation which may contribute to tumorigenesis in papillary thyroid carcinoma. patients with distant metastatic parathyroid tumors. Design: Between June 1973 and August 2007, totally 2281 patients underwent 506 Papillary Oncocytic Neoplasms of the Thyroid parathyroidectomy (PTx) for secondary HPT in our hospital. We encountered five RL Woodford, JL Hunt, AM Bellizzi, X Zhang, SE Mills, EB Stelow. University of Virginia, (0.22%) patients with distant metastatic parathyroid tumors. We selected the eight Charlottesville, VA; Cleveland Clinic Foundation, Cleveland, OH. primary parathyroid glands removed from the neck at the initial and/or re-operation and Background: Papillary oncocytic neoplasms (PONs) of the thyroid are exceedingly seven distant metastatic tumors surgically resected. All materials were fixed by 10% rare entities, whose relationship to other thyroid tumors has not been thoroughly formalin, and embedded in paraffin. After antigen retrieval was by microwave in 10 elucidated. While some believe they represent variants of papillary thyroid carcinoma mmol citrate buffer (pH6.0), mouse monoclonal antiparafibromin antibody (SC-3368, (PTC), others believe them to be follicular neoplasms. This study used morphologic Santa Cruz,CA) were applied. examination, immunohistochemistry (IHC), and BRAF gene analysis to refine the Results: In only one lung metastatic parathyroid carcinoma, negative staining for classification of PONs. parafibromin was detected. In the other three lung, two regional lymph node and one Design: PONs were defined as thyroid neoplasms composed of oncocytic thyrocytes with chest wall metastatic parathyroid carcinomas, parafibromin was strongly stained in at least a focal papillary architecture and without nuclear features diagnostic of PTC. the nuclei of the parathyroid cells. Among eight primary carcinomas except for one Twelve cases fitting these criteria were identified. Patient age, sex, and tumor focality with weakly positive staining, the expression of parafibromin was detected diffusely were noted. Tumor architecture, capsular features, nuclear features, calcifications, and strongly. 112A ANNUAL MEETING ABSTRACTS necrosis, and adjacent thyroid pathology were assessed. IHC for CK19 and HBME1 the 8 patients with Paget cells (including the 3 index biopsies) there were no differences was performed. Microdissection, PCR, and sequencing of exon 15 of the BRAF gene in gender (p=0.58) or age (p=0.78) as compared to 103 adenocarcinomas without Paget were also completed. cells. Morphologically, all cases with Paget cells contained at least a component of Results: Ages ranged from 14-77 (median 59) and there were 11 women and 1 man. diffuse, poorly differentiated carcinoma (one was a signet ring cell carcinoma), and All tumors were unifocal and half had a predominantly papillary architecture (>50% Paget cells involved only squamous epithelium directly above the poorly differentiated of the tumor). Microfollicular and solid growth patterns were also occasionally noted. foci. Their staining profile was as follows (one case unavailable): PAS-D+ (7/7, 100%), Papillary fronds were lined by a single layer of cuboidal to columnar cells with oncocytic mucicarmine+ (6/7, 86%), CK7+ (7/7, 100%), CK20+ (5/7, 71%), p53 overexpression cytoplasm and prominent hobnailing. Nuclei were most often centrally located, (3/7, 43%), and E-cadherin loss (complete in 1 and faint in 3, 57%). A control group of although two tumors had uniformly apical nuclei. Chromatin was fine and dispersed 19 adenocarcinomas without Paget cells were also stained for E-cadherin; only 1 (5%) and small nucleoli were present with varied prominence. Mitotic activity was rare and showed faint expression and none had complete loss (p=0.01). all but 2 cases had minimal to mild nuclear atypia. Although rare nuclear features of Conclusions: Unlike mammary, vulvar, and perianal PD, esophageal Paget cells are PTC were seen in 3 cases, no cases, by definition had sufficient changes to warrant a almost universally associated with underlying adenocarcinoma (prevalence of secondary diagnosis of PTC. All tumors were encapsulated. Extracapsular extension (1/12) and esophageal PD = 4.9%) and not with high grade dysplasia (“in situ” disease) or primary vascular invasion (6/12) were sometimes noted. Calcifications (3/12) and definitive PD. A commonality among cases with Paget cells is the presence of focal or diffuse, psammoma bodies (1/12) were rare. Adjacent thyroid pathology included nodular poorly differentiated adenocarcinoma with discohesive cells. E-cadherin alterations hyperplasia (4/12), mild lymphocytic thyroiditis (1/12), and one minimally invasive also appear to play a role. follicular carcinoma. No cases were immunoreactive with antibodies to HBME1 and only 1 of 9 was immunoreactive with antibodies to CK19. No BRAF point mutations 509 Quantitative Immunohistochemistry of Mast Cells in the were identified (0/9). Analysis of Colorectal Carcinogenesis Conclusions: PONs are histologically, immunohistochemically, and molecularly distinct CE Aguilar, M Zhang, GY Yang. Northwestern University, Chicago, IL. from PTC and appear to be most related to follicular neoplasms. If the diagnostic criteria Background: Mast cells have been implicated in tumor progression and prognosis in for follicular neoplasms were used, more than half of the tumors would be considered part because of their hypothesized role in angiogenesis. A significant increase in the minimally invasive or angioinvasive carcinomas. number of mast cells has been observed in Min/+ mouse models of familial polyposis disease. Given the emerging link between cancer and inflammation and the recognized 507 PPARδ Is Over Expressed in Thyroid Tumors and Regulates role of mast cells as central effectors in inflammatory reactions, the aim of this work Proliferation in Primary Thyroid Cells was to study the potential role of mast cells in colorectal carcinogenesis by semi- L Zeng, M Tretiakova, X Yu, P Michalewicz, TG Kroll. University of Chicago School quantifying the number of mast cells in premalignant conditions including tubular of Medicine, Chicago, IL. adenomas with/without high grade dysplasia and hyperplastic polyps in comparison Background: Peroxisome proliferator-activated receptors (PPARs) are ligand-regulated with normal mucosa. transcription factors that have been implicated in lipid metabolism and the pathogenesis Design: Hyperplastic polyps (n=27), tubular adenomas (n=30), and tubular adenomas of thyroid tumors. Here, we determine that PPARδ is over expressed in thyroid tumors with high grade dysplasia (n=20) were selected from archived pathological specimens at and regulates proliferation in thyroid cells. our institution. Mast cells were detected immunohistochemically with mast cell tryptase Design: Thyroid tissue microarrays were constructed with 18 follicular adenomas, 20 antibody and the avidin-biotin-peroxidase approach. Mast cells were semi-quantified follicular carcinomas, 37 papillary carcinomas, 9 Hurthle cell adenomas, 9 Hurthle for at least ten microscopic fields at a magnification of 40X. cell carcinomas, 10 poorly differentiated/anaplastic carcinomas and 76 normal thyroid Results: Tryptase strongly labeled mast cells in the lamina propria of colonic mucosa tissues (ATA-27, Beecher Instruments). Immunohistochemistry was performed with and polypoid lesions. Positive staining was confined to the cytoplasm. Semi-quantitative microwave antigen retrieval and EnVision (non-biotin) detection (DAKO) using analysis of mast cells was performed. In normal mucosa, the mean number of mast antibodies against PPARδ (H-74, Santa Cruz) and Ki67 (Ki-S5, DAKO). Expression cells was 14.8 ± 3.7 (R: 11.7-22.3). In the premalignant conditions, the mean number levels were quantitated with the Automated Cellular Imaging System (Chromovision) of mast cells was 21.2 ± 7.1 (R: 10.0-39.8) in hyperplastic polyps, 21.2 ± 4.4 in tubular that recorded positive nuclear and cytoplasmic staining as a numerical score between adenomas (R: 12.3-32), and 18.4 ± 4.2 in high grade tubular adenomas. 0 and 225 normalized to an area of 1 um2. Brown positive staining was differentiated Conclusions: Our results demonstrate marked lamina propria infiltration by mast cells from blue negative counterer staining. p values were calculated using the Student’s t and in hyperplastic and adenomatous polyps, suggesting mast cell-mediated inflammation Spearman rank correlation tests. Immunoblots were performed with chemi-luminesence may be involved in early-stage colorectal carcinogenesis. Further study of mast cell- detection. PPARδ was over expressed by electroporation and knocked down by siRNA mediated inflammation in colorectal carcinogenesis is warranted. in primary human thyroid cells. Thyroid cell proliferation was determined by the incorporation of BrdU. 510 Overexpression of SmgGDS in Colon Carcinoma Results: The expression of native PPARδ was elevated 3- to 5-fold in follicular DV Baewer, F Anwar, GA Dawson, Q Xiang, CL Williams, R Komorowski, R Li. Medical adenomas (208.44, p<0.0001), follicular carcinomas (221.63, p<0.0001), papillary College of Wisconsin, Milwaukee, WI. carcinomas (394.11, p<0.0001), Hurthle cell adenomas (352.67, p<0.0001), Hurthle cell Background: SmgGDS is a guanine nucleotide exchange factor with the unique carcinomas (293.89, p<0.0001) and poorly differentiated/anaplastic carcinomas (438.60, ability to activate multiple small GTPases, implicating it in cancer development and p<0.0001) compared to normal thyroid tissues (75.19). Mean levels of PPARδ correlated progression. We previously demonstrated that SmgGDS is overexpressed in prostate, directly with those of Ki67 (R=0.8571; p=0.02381) in the thyroid tumors. PPARδ ligand breast and lung carcinomas, indicating a potential role as a diagnostic and prognostic induced proliferation in primary thyroid cells. Engineered over expression of PPARδ marker in these tumors. We also showed that reduction of SmgGDS expression using increased BrdU incorporation 55%, phospho-Rb 200% and cyclin E1 900% in just 2 siRNA in different cancer cells inhibits cell proliferation and reduces cell migration, days. Knockdown of PPARδ by siRNA inhibited proliferation 45%. further suggesting that SmgGDS may be a potential target in the treatment of these Conclusions: Our experiments demonstrate that PPARδ is over expressed in many cancers. The expression and function of SmgGDS in colon cancer has not been reported. benign and malignant thyroid tumors. PPARδ appears to regulate proliferation in thyroid In this study, we evaluated the expression of SmgGDS in a large series of colon cancer cells by modulating cyclin E1. These findings suggest that that PPARδ coordinates cell cases including invasive carcinoma (InvCa), tubular adenoma/carcinoma in situ (TA/ proliferation with lipid metabolism in a physiologic process that is deregulated during CIS) and metastatic carcinoma (Met) using immunohistochemistry (IHC). thyroid tumorigenesis. Design: A total of 163 primary InvCa cases, as well as 53 TA/CIS and 38 Met identified from the 163 cases, were selected and stained with monoclonal anti-SmgGDS antibody. Tumors having stronger intensity and/or more area of staining were considered as Gastrointestinal overexpression when compared with the adjacent benign epithelium. Results: 1. SmgGDS is overexpressed in colon cancers (see table 1). 2. Overexpression 508 Paget Cells in the Esophagus: Assessment of Their of SmgGDS is identified at different stages of tumor development in same patients. Histopathologic Features and Near-Universal Association with Underlying The expression is strongly correlated between InvCa and TA/CIS (n = 53, K = 0.89, p Adenocarcinoma = 6.1E-09) and Met (n = 38, K = 0.58, p = 0.0003). 3. Expression of SmgGDS in colon SC Abraham, H Wang, KK Wang, T-T Wu. MD Anderson Cancer Center, Houston, TX; cancer is independent of tumor stage and grade. Mayo Clinic, Rochester, MN. Overexpression of SmgGDS in Colon cancer Background: Esophageal Paget disease (PD) – intraepithelial growth of neoplastic cells InvCa TA/CIS Met with glandular differentiation – has only rarely been reported. We recently encountered 123/163 (75.5%) 42/53 (79.2%) 31/38 (81.6%) 3 endoscopic biopsies containing Paget cells in association with adenocarcinomas of Conclusions: 1. SmgGDS is overexpressed in different stages of colon cancer, indicating Barrett esophagus (BE) or the esopahgogastric junction. The aim of this study was to a potential role as a diagnostic and prognostic marker of colon cancer. 2. The increased evaluate the prevalence of primary and secondary esophageal PD and its histochemical SmgGDS expression in TA/CIS suggests its role in early colon carcinogenesis. 3. These and immunohistochemical profile. findings suggest that SmgGDS may hold value as a marker for tumor diagnosis or a Design: To search for primary esophageal PD, we reviewed the computerized database target for the prevention and treatment of colon cancer. at our institution from 1994-2007. For secondary PD, we studied 108 adenocarcinomas (81 EMRs + 27 esophagectomies) and 72 BE with high grade dysplasia (47 EMRs + 511 p16INK4a Is Surrogate Marker of High-Risk HPV in High-Grade 25 esophagectomies). Cases with Paget cells (including index biopsies) were subjected Squamous Lesions and Invasive Carcinomas of the Anal Canal, but Not to histochemistry for PAS-D and mucicarmine, and immunohistochemistry for CK7, in Anal Condyloma CK20, p53, and E-cadherin. R Balasubramaniam, CS Kong, J Erickson, N Pourmand, ML Welton, TA Longacre. Results: There were no cases of primary esophageal PD over a 13 year span. In contrast, Stanford University, Stanford, CA. Paget cells were present in squamous epithelium overlying 5/108 esopahgeal/EG Background: p16INK4a is used as a surrogate marker for high-risk HPV (HR-HPV) junction adenocarcinomas, yielding a 4.9% prevalence of secondary PD. None (0%) in the uterine cervix, and has proven useful in the diagnosis of cervical squamous of 72 BE with high grade dysplasia (“in situ” disease) had Paget cells (p=0.16). Among