VOLUME 32 | SUPPLEMENT 2 | MARCH 2019 MODERN PATHOLOGY

2019 ABSTRACTS PANCREAS, GALLBLADDER, AMPULLA, AND  EXTRA-HEPATIC  BILIARY TREE (1667-1734)

MARCH 16-21, 2019 PLATF OR M & 2 01 9 ABSTRACTS P OSTER PRESENTATI ONS

EDUCATI ON C O M MITTEE

Jason L. Hornick , C h air Ja mes R. Cook R h o n d a K. Y a nti s s, Chair, Abstract Revie w Board S ar a h M. Dr y and Assign ment Co m mittee Willi a m C. F a q ui n Laura W. La mps , Chair, C ME Subco m mittee C ar ol F. F ar v er St e v e n D. Billi n g s , Interactive Microscopy Subco m mittee Y uri F e d ori w Shree G. Shar ma , Infor matics Subco m mittee Meera R. Ha meed R aj a R. S e et h al a , Short Course Coordinator Mi c h ell e S. Hir s c h Il a n W ei nr e b , Subco m mittee for Unique Live Course Offerings Laksh mi Priya Kunju D a vi d B. K a mi n s k y ( Ex- Of ici o) A n n a M ari e M ulli g a n Aleodor ( Doru) Andea Ri s h P ai Zubair Baloch Vi nita Parkas h Olca Bast urk A nil P ar w a ni Gregory R. Bean , Pat h ol o gist-i n- Trai ni n g D e e p a P atil D a ni el J. Br at K wun Wah Wen , Pat h ol o gist-i n- Trai ni n g Ashley M. Ci mino- Mathe ws

ABSTRACT REVIE W B OARD

Benja min Ada m Ta mara Giorgadze Ta mara Lotan Steven Salvatore Mi c h ell e Af k h a mi Raul Gonzalez Anthony Magliocco Souzan Sanati Narasi mhan ( Narsi) Agara m Purva Gopal Kr uti M a ni ar Sandro Santagata R o u b a Ali- F e h mi Anuradha Gopalan Jonathan Marotti A nj ali S a qi G h a s s a n All o Jennifer Gordetsky E mil y M a s o n Frank Schneider Isabel Alvarado- Cabrero Rondell Graha m Jerri McLe more Jeanne Shen C hristi na Ar n ol d Alejandro Gru Bruce Mc Manus Ji a qi S hi Rohit Bhargava Nil e s h G u pt a David Meredith Wun-Ju Shieh Justin Bishop Ma mta Gupta A n n e Mill s G a bri el Si c a Jennifer Boland Kriszti na Ha nley Neda Moata med D e e pi k a Sir o hi Ele na Brac htel Douglas Hart man Sara Monaco K alli o pi Si zi o pi k o u M aril y n B ui Yael He her Atis Muehlenbachs Lauren S mith S helley Calt har p Walter He nricks Bit a N ai ni Sara Szabo Joanna Chan J o h n Hi g gi n s Di a n n a N g J ulie Ter uya-Fel dstei n Jennifer Chap man M ai H o a n g Tony Ng Gaetano Thiene H ui C h e n M oj g a n H o s s ei ni Ericka Ol gaar d Khin Th way Yi n g b ei C h e n Aaron Huber Jac q ueli ne Parai Rash mi Tondon Benja min Chen P et er Ill ei Yan Peng Jose Torrealba Rebecca Chernock D oi n a I v a n D a vi d Pi s a pi a E vi V a ki a ni Bet h Clark W ei Ji a n g Alexandros Polydorides Christopher VandenBussche Ja mes Conner Vi c ki e J o Sona m Prakash Sonal Var ma Alejandro Contreras Kirk J o nes Manju Prasad E n di W a n g Cla u di u C otta Neerja Ka mbha m Peter Pytel Christopher Weber Ti mothy D’ Alfonso Chiah Sui ( Sunny) Kao Joseph Rabban Olga Weinberg Farbod Darvishian Dipti Kara mchandani Stanley Radio Sara Wobker Jessica Davis Darcy Kerr E mad Rakha Mi n a X u Heather Da wson Ashraf Khan Preetha Ra malinga m Shaofeng Yan Elizabeth De micco Rebecca King Pri y a R a o A nj a n a Y el d a n di Suzanne Dintzis Mi c h a el Kl u k Robyn Reed A ki hi k o Y o s hi d a Mi c h ell e D o w n e s Kristine Konopka Mi c h ell e R ei d Gl ori a Y o u n g D a ni el D y e Gre g or Kri n gs Natasha Rekht man Minghao Zhong Andre w Evans Asangi Ku marapeli Mi c h a el Ri v er a Y a oli n Z h o u Mi c h a el F e el y Alvaro Laga Mi c h a el R o h Hongfa Zhu De n nis Firc ha u Cheng- Han Lee Andres Ro ma Debra Zynger Larissa F urta d o Z ai b o Li Avi Rosenberg A nt h o n y Gill H ai y a n Li u Est her ( Dia na) R ossi R y a n Gill Xi uli Li u Peter Sado w P a ul a Gi nt er Yen- Chun Liu S a i a S al ari a

T o cit e a b str a ct s i n t hi s p u bli c ati o n, pl e a s e u s e t h e f oll o wi n g f or m at: A ut h or A, A ut h or B, A ut h or C, et al. A b str a ct titl e ( a b s #). I n “ Fil e Titl e. ” Modern Pathology 2019; 32 (s u p pl 2): pa ge#

1667 Intracholecystic Papillary-Tubular Neoplasms: Is a Size Cut-Off Justified? Heba Abdelal1, Deyali Chatterjee2 1Washington University School of Medicine, St. Louis, MO, 2Washington University, St. Louis, MO

Disclosures: Heba Abdelal: None; Deyali Chatterjee: None

Background: In the current WHO classification of tumors of the gallbladder (2010), polypoid well-demarcated intra-cholecystic lesions are classified as adenomas or intracystic papillary neoplasms, without a clear demarcation between the two entities. The term intracholecystic papillary-tubular neoplasms (ICPN) has subsequently been suggested to encompass all discrete noninvasive epithelial neoplasms in gallbladder, including adenomas. There is also a general consensus to use a size cut-off of 1 cm for ICPN. In our study, we wanted to explore the prognostic significance of smaller discrete polypoid lesions < 1cm (PL) in gallbladder, and how they relate to conventional ICPN.

Design: We searched our pathology database for all retrospective cholecystectomies (1995-2017) which had a grossly identifiable discrete polypoid lesion, and slides available for review. Polypoid lesions microscopically showing a cellular proliferation of glandular elements, arranged in various combinations of tubular and/or papillary configuration, were selected. Focal mucosal papillary hyperplasia in relation to chronic cholecystitis or cholesterolosis, and polypoid adenomyoma were excluded. Cases were classified based on greatest gross dimension, into PL (< 1cm) and ICPN (>=1cm). The clinical and follow-up information were reviewed from the electronic medical records.

Results: In our cohort, there were 22 cholecystectomy specimens (from 8 males, 14 females; with mean age 61 years), all of which were received grossly intact. 6 among them were classified as PL, and 16 as ICPN. The clinicopathologic details for the two groups are outlined in Table 1. Both groups showed similar histologic features in terms of epithelial composition, dysplasia within lesion, background flat epithelial dysplasia, or associated invasive . On follow-up, one patient each from non-invasive PL and ICPN cases, subsequently developed a biliary malignancy.

Clinicopathologic PL (< 1cm) ICPN (>=1cm) features Average size 0.4 (0.2-0.7) 1.9 (1-4.3) Total cases 6 (F=5, M=1) 16 (F=9, M=7) mean age (years) 59.7 62.5 Multiplicity of lesions 2 (33.3%) 5 (31.3%) Multiplicity of epithelial 2 (33.3%) 9 (56.3%) components Epithelial types (in Biliary (4), gastric (3), Biliary (14), gastric (5), number of lesions) intestinal (1), clear cell intestinal (3), oncocytic change (1) (1) Cytologic dysplasia 3 (50%) 14 (87.5%)

(low grade- 1, high (low grade-2, grade- 2) high grade-12) Associated invasive 1 (16.7%) 6 (37.5%) carcinoma Background flat 2 (33.3%); low grade 9 (56.3%); dysplasia (low grade- 6,

high grade-3) Subsequent biliary 1 of 5 (20%) 1 of 10 (10%) malignancy for non- invasive lesions Association with 4 (66.7%) 8 (50%) chronic cholecystitis Association with 3 (50%) 7 (43.8%) cholelithiasis Association with 1 (16.7%) 5 (31.3%) cholesterolosis Association with 1 (16.7%) 2 (12.5%) primary sclerosing cholangitis

Conclusions: Our study shows that clinical and pathologic findings between the two groups (PL and ICPN) are similar. Although the risk of high-grade dysplasia and invasive adenocarcinoma increases with size of the non-invasive lesion, they can be present in lesions less than 1 cm as well. There is also a subsequent risk of developing biliary tract malignancy elsewhere even if the lesion in gallbladder is less than 1 cm. Therefore, we feel, all discrete polypoid lesions in gallbladder have similar neoplastic potential and can be considered as ICPN irrespective of their size.

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1668 Intraoperative Electroporation: Initial Observations In Whipple Resection Specimens Andrea Agualimpia Garcia1, Sarah Hackman1, Danielle Fritze1, Daniel Mais2 1UT Health San Antonio, San Antonio, TX, 2The University of Texas Health Science Center at San Antonio, San Antonio, TX

Disclosures: Andrea Agualimpia Garcia: None; Sarah Hackman: None; Danielle Fritze: None; Daniel Mais: None

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