Adenomatoid Tumor of the Ovary: an Immunohistochemical and Ultrastructural Study

Toshio Hirakawa, M.D., Masazumi Tsuneyoshi, M.D. and Munetomo Enjoji, M.D.* Second Department of Pathology, Faculty of Medicine, Kyushu University 60, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812 Downloaded from https://academic.oup.com/jjco/article/18/2/159/898496 by guest on 25 September 2021

Abstract

A rare case of adenomatoid tumor arising in the ovary is presented. At autopsy on a 61-year-old woman, a soft, solid and cystic tumor, measuring 0.8 X 0.7 cm, was detected in the hilus of the left ovary. Light microscopic study showed char- acteristic features of adenomatoid tumor. Alcian blue stain, with and without hyaluronidasc pretreatment, revealed the presence of hyaluronic acid on the luminal surface and in the vacuoles of the tumor cells. Immunohistochemical stains of tumor cells were positive for low-molecular-weight cytokeratin (PKK.1), vimentin, and carbohydrate antigen (CA) 125, whereas they were focally positive for high- molecular-weight cytokeratin (348E12). They were negative for factor Vlll-related antigen (FVIII-RAG), Ulex europaeus I lectin (UEA I), carcinoembryonic antigen (CEA) and epithelial membrane antigen (EMA). Ultrastructural studies disclosed surface microvilli and bundles of tonofilaments. These observations strongly support the idea of this tumor being of mesothelial origin.

Upn. J. Clin. Oncol. 18: 159-166, 1988) Key words: Adenomatoid tumor—Ovary—Immunohistochemistry—Ultrastruc- ture

Introduction Case Report

Adenomatoid tumor originates mainly in A 61-year-old Japanese woman was ad- the genital system: epididymis, fallopian tube mitted to Kyushu University Hospital with and uterus, and is one of the rarest ovarian a rapidly enlarging tumor of the left neck. neoplasms.1' The histogenesis of the adeno- Radiation, chemotherapy and hyperthermia matoid tumor remains controversial. It is were administered but she died one year generally regarded as being of mesothelial later. Autopsy revealed a poorly differenti- origin,2"7' but some cases of endothelial ated adenocarcinoma arising in the head of origin have been documented.8"10' the pancreas with widespread metastasis. The We report here a case of adenomatoid tumor of the left neck proved to be a metas- tumor of the ovary, and the light micro- tasis of the pancreatic carcinoma. A small scopic, histochemical, immunohistochemical nodule was incidentally detected in the left and ultrastructural features are described. ovary.

Methods Received: December 19, 1987. Accepted: February 10, 1988. Ten percent formalin-fixed, paraffin-em- *For reprints and all correspondence. bedded materials were used for light mi-

18(2) 1988 159 HIRAKAWA ET AL.

Table I. Primary Antibodies Used

Antibody Source Dilution Cytokeratins, monoclonal Cytokeratin PKK1 Labsystems 1:300 Cytokeratin 34/9E12 Enzo Biochem 1:2000 Vimentin, monoclonal Dakopatts 1: 100 Carbohydrate antigen (CA) 125, monoclonal CIS 1: 10

Factor VUI-related antigen (FVIII-RAG), Downloaded from https://academic.oup.com/jjco/article/18/2/159/898496 by guest on 25 September 2021 polyclonal Dakopatu 1:500 Ulex europaeus I lectin (UEA I), HRP*-conjugated Vector Lab. 10 mcg/ml Carcinoembryonic antigen (CEA), polyclonal Zymed Lab. 1: 100 Epithelial membrane antigen (EMA), monoclonal Dakopatu 1: 100

* HRP, honermdUh peroxidaK. croscopic, histochemical and immunohisto- reagents were purchased from BioGenex chemical studies. Tissue specimens were cut Laboratories (StrAviGen B-SA immunostain- and stained with hematoxylin and eosin ing kits No. 295007 and 295008, Dublin, (H.E.), alcian blue with and without pre- CA, U.S.A.). The application of biotinylated treatment of testicular (bovine testis H-3506, anti-immunoglobulin antibody was skipped Sigma Chemical Co., St. Louis, MO, U.S.A.) in the slides treated with horseradish per- and streptomyces hyaluronidase (Strepto- oxidase-conjugated Ulex europaeus I lectin myces hyalurolyticus No. 100740, Seikagaku (UEA I). The sections were rinsed with Kogyo, Tokyo), periodic acid-Schiff (PAS), three bath changes of PBS between all in- mucicarmine, Masson's trichrome, silver im- cubations. The reaction was developed with pregnation for reticulin and elastica van diaminobenzidine and hydrogen peroxidase. Gieson. Counterstaining was performed with methyl For the immunohistochemical study, Bio- green. tin-StreptAvidin (B-SA) Amplified system, a For the electron microscopic study, small modification of the avidin-biotin-peroxidase blocks of formalin-fixed tissues were post- complex (ABC) method of Hsu et al.,lx) fixed in 3% glutaraldehyde solution (buff- was applied. Five micron sections were de- ered at pH 7.4) and then in 1% phosphate- paraffinated with xylene and rehydrated in buffered osmium tetroxide. Following de- a graded series of alcohol. The sections for hydration, the tissue blocks were embedded cytokeratins were treated with 0.1% trypsin in Epon 812, and cut on an ultramicrotome. (Type II, pancreatic No. T-8003, Sigma Ultrathin sections were stained with uranyl Chemical Co.) in phosphate-buffered saline acetate and lead citrate, and examined in (PBS; pH 7.4) at 37°C for thirty minutes. an electron microscope. All sections were incubated in 0.3% hydrogen peroxidase in methanol for thirty min- Pathology utes and subsequently exposed overnight at 4°C to the primary antibodies at given dilu- Grossly, the tumor was located at the tions (Table I). PKK1 recognizes low-mo- hilus of the left ovary (Fig. 1). It was a lecular-weight cytokeratin proteins of 44 ,46, grayish white, solid and cystic, spongy soft, 52 and 54 kD, whereas 346E12 recognizes poorly circumscribed mass, measuring 0.8 X high-molecular-weight cytokeratin proteins 0.7 cm. Between the tumor and the ovarian of 57 and 66 kD. Biotin and streptavidin surface was an inclusion cyst 0.9 cm in di-

160 Jpn. J. Clin. Oncol. OVARIAN ADENOMATO1D TUMOR ameter. The tumor had no apparent relation vacuoles of varying sizes in the stroma (Figs. to the fallopian tube or uterus. The other 2 and 3). Tumor cells contained round to pelvic organs were unremarkable. oval nuclei with an eosinophilic cytoplasm. Light microscopic sections presented the Occasionally, the nuclei were displaced by typical appearance of a common adeno- cytoplasmic vacuoles, giving the appearance matoid tumor, with anastomosing gland-like of signet-ring cells. Nuclear atypia or mitotic spaces lined by flattened or cuboidal cells, figures were absent, which clearly distin-

or small clusters of tumor cells containing guished the lesion from the metastatic pan- Downloaded from https://academic.oup.com/jjco/article/18/2/159/898496 by guest on 25 September 2021 creatic carcinoma. Some nuclear grooves were evident. The luminal surface was often fluffy and resembled a brush border. The stroma was relatively loose and contained elastic and collagen fibers and fibroblasts. Elastic fibers were recognized as an eosinophilic, fibrillar or granular structure on the H.E. section and were also demonstrable by elastica van Gieson's stain. Small aggregates of lymphocytes were present in the stroma. Smooth muscle cells were absent, except for the vascular wall. The inclusion cyst adja- cent to the tumor was lined with a single layer of ciliated cuboidal epithelium. There Fig. 1. Sectioned surface of the left ovary was no transition between the cyst and the showing adenomatoid tumor in the hilus (arrow). An inclusion cyst is present between tumor. the tumor and the serosal surface (arrow head). Alcian blue-positive material was present

Fig. 2. Adenomatoid tumor characterized by anastomosing gland-like spaces and small clusters of vacuolated tumor cells. The stroma is infiltrated by lymphocytes (hematoxylin and eosin X 118).

18(2) 1988 lfil HIRAKAWA ET AL.

negative. Mucicarmine stain showed a faint '. t/ft positivity in the luminal surface and vacuoles. Masson's trichrome stain revealed small numbers of collagen fibers in the stroma, and confirmed the absence of smooth muscle cells except in the vascular wall. Silver im- pregnation for reticulin disclosed reticulin

fibers encircling the channels and nests of Downloaded from https://academic.oup.com/jjco/article/18/2/159/898496 by guest on 25 September 2021 >: >'<• tumor cells. Immunohistochemically, tumor cells were \ \ diffusely positive for both low-molecular- weight cytokeratin (PKK1) (Fig. 4a) and vimentin (Fig. 4b) in the cytoplasm and '<,•' for carbohydrate antigen (CA) 125 on the luminal surface (Fig. 4c). They showed focal cytoplasmic positivity for high-molecular- weight cytokeratin (34BE12). Factor VIII- .»*. related antigen (FVIII-RAG), UEA I, carcinoembryonic antigen (CEA) and epithelial membrane antigen (EMA) were negative. Ultrastructural studies of the tumor cells revealed dilated intercellular and intracellu- Fig. 3. Higher magnification of Fig. 2. The lar spaces, and the tumor cells had abundant spaces are lined by flattened or cuboidal cells. Tumor cells in the stroma contain vacuoles of cytoplasmic microvilli lining the luminal varying sizes and show an appearance of signet- surface (Fig. 5a) and bundles of tonofila- ring cells (hematoxylin and eosin X 270). ments in the cytoplasm (Fig. 5b). Occasion- al desmosome-like structures were observed and basal lamina covering the surface of on the luminal surface and in the vacuoles the cytoplasm was sometimes evident. of tumor cells. This material was digested with either testicular or streptomyces hy- Discussion aluronidase, but some positivity remained even after digestion. The PAS stain was Occurrence of an adenomatoid tumor in

Table II. Clinicopathologic Features of Adenomatoid Tumors of the Ovary

Case No. AB-positive Electron Age Side Location Size (cm) material microscopy

1. Moreheadm 26 R Almost completely NS NS NS replaced the ovary 2. Lee, et a/.'1' 39 R Anteromedial 1.4x 1 NS NS aspect of the ovary 3. Williamson and NS R ? medulla 3 absent NS Moore14' 4. Ferenczy, et a/.15' 44 R hilus 0.7x0.6 present mesothelial-like 5. Bell and Flotte" 57 R hilus NS NS mesothelial-like 6. Present case 61 L hilus 0.8x0.7 present mesothelial-like

NS, not itated; R, right; L, left; AB, alcian blue.

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•* " 1

4 b.

Fig. 4. a. The cytoplasm of tumor cells stains positive for low-molecular-weight cytokeratin (PKK1) (immunoperoxidase X 280). b. Tumor cells stain positive for vimentin (immunoperoxidase X 280). c. Luminal surface of tumor cells stains positive for CA 125 (immunoperoxidase X 280). the ovary is extremely rare, and only five 26 to 61 years. All occurrences were uni- well documented cases have appeared in lateral. Four were located in the right ovary the English literature, as listed in Table and one in the left. Three cases were located Tj o, 12-ir,) Adding the present case to the in the hilus of the ovary. In another one, five, the ages of the six patients ranged from the ovary was almost completely replaced by

18(2) 1988 163 HIRAKAWA ET AL. Downloaded from https://academic.oup.com/jjco/article/18/2/159/898496 by guest on 25 September 2021

Fig. 5. a. Note the numerous microvilli on the luminal surface (L) of the tumor cells (X 8,000). b. Bundles of tonofilaments are present in the cytoplasm (X 8,000).

the tumor and the other was reported to be and it seemed to have arisen in the medulla on the anteromedial aspect of the ovary. For of the ovary. Size of tumor varied from 0.7 one case, the location was not clearly stated to 3 cm in diameter. The tumors were solid

164 Jpn. J. Clin. Oncol. OVARIAN ADENOMATOID TUMOR or contained small cysts and were well cir- tive expression of CA 125 in adenomatoid cumscribed except for one. The patients tumors is useful in diagnosis. Bolen et a/.21' were asymptomatic or complained of ab- termed reactive non-neoplastic subserosal dominal pain. The tumors were detected cells as multipotential subserosal cells. These incidentally at laparotomy or autopsy. The cells express both low-molecular-weight cy- associated pathological findings were a cyst tokeratin and vimentin and have a capacity in the contralateral ovary removed 18 for surface mesothelial differentiation dur- months previously,12' fibromyomas of the ing which they acquire high-molecular- uterus and hydrosalpinx13' and breast carci- weight cytokeratin and progressively lose Downloaded from https://academic.oup.com/jjco/article/18/2/159/898496 by guest on 25 September 2021 noma.15' Although data on the follow-up are vimentin.-'11 The immunohistochemical fea- limited, one showed no evidence of disease ture of the present case resembles that of two years after surgery.9' Adenomatoid tu- the multipotential subserosal cells in the co- mors of other sites are generally benign, but expression of low-molecular-weight cytokera- some in the paratesticular region are re- tin and vimentin and the paucity of high- ported as malignant.16' molecular-weight cytokeratin. The possibility Histochemically, adenomatoid tumors con- of adenomatoid tumors being derived from tain acid mucopolysaccharide which stains these cells remains to be examined. with alcian blue and is digested with hy- Ultrastructurally, tumor cells were charac- aluronidase.7'171 By the use of streptomyces terized by numerous microvilli projected on hyaluronidase, which is specific to the the luminal surface, desmosome-like struc- hyaluronic acid, the present study confirmed tures, bundles of tonofilaments, well-devel- the presence of hyaluronic acid in adeno- oped basal lamina and wide inter- and intra- matoid tumor of the ovary, hence the meso- cellular spaces.7' ir'- 17) thelial nature of the lesion. Akhtar et al.17> The histogenesis of adenomatoid tumor is noted elastic fibers and active elastogenesis controversial. Most studies support a meso- in an adenomatoid tumor of the round liga- thelial histogenesis, although some examples ment. Numerous elastic fibers were also ob- of endothelial origin have been reported in served in the present pathology. epididymal8-fl) and uterine101 lesions, deter- Several immunohistochemical studies re- mined from electron microscopy*' and im- vealed that adenomatoid tumors were posi- munoperoxidase staining of FVIII-RAG.0' 10) tive for keratin2"*" or cytokeratin (PKK1),7) Our histochemical, immunohistochemical and whereas they were negative for FVIII- ultrastructural studies strongly suggested a RAG,2~7> UEA I,4- '•• 7> and CEA.3' r'» These mesothelial origin. results, suggesting a mesothelial origin, are Adenomatoid tumors should be distin- consistent with findings in the present study. guished from other tumors of mesothelial Vimentin was reported to be negative in origin such as cystic mesothelioma of the adenomatoid tumor,4' but was positive in peritoneum and rarely as malignant mesothe- the present study. Mesotheliomas has been lioma. Cystic mesothelioma of the perito- reported to be positive for EMA,18' but the neum consists of a single layer of uniform stainability in adenomatoid tumors is de- mesothelial cells lacking significant atypia batable. Some studies revealed positive,5'1(" and is located on the peritoneal surface. It but another negative.6' There has been no has been regarded as a clinically "borderline" report concerning the stainability of CA 125 variant between benign (adenomatoid tu- in adenomatoid tumors. CA 125 is expressed mor) and malignant mesotheliomas of the in normal adult and fetal tissues of coelomic peritoneum because of local recurrence re- origin, as well as in neoplasms derived from ported on occasions.22' The present case is these tissues, but some tumors of noncoelomic naturally considered to be an adenomatoid origin also express this antigen.2fl) The posi- tumor because of its location in the ovarian

18(2) 1988 165 HIRAKAWA ET AL. hilus. Hsu, S. M., Raine, L. and Fanger, H. The use of avidin-biotin-peroxidase complex Acknowledgments (ABC) in immunoperoxidase techniques: a comparison between ABC and unlabeled We thank Prof. K. Sueishi and Dr. K. Maeda, antibody (PAP) procedures. /. Histochem. First Department of Pathology, Kyushu Univer- Cytochem. 29, 577-580 (1981). sity, for providing the tissue specimens, and M. 12) Morehead, R. P. Angiomatoid formations in Ohara for comments on the manuscript. the genital organs with and without tumor formation. Arch. Pathol. 42, 56-63 (1946). Lee, M. J. Jr., Dockerty, M. B., Thompson, References 13) Downloaded from https://academic.oup.com/jjco/article/18/2/159/898496 by guest on 25 September 2021 G. J. and Waugh, J. M. Benign mesothe- 1) Czernobilsky, B. Primary epithelial tumors liomas (adenomatoid tumors) of the genital of the ovary in "Pathology of the Female tract. Surg. Gynecol. Obstet. 91, 221-231 Genital Tract, 2nd ed.," ed. A. Blaustein, (1950). pp. 511-560 (1982). Springer-Verlag, New 14\ Williamson, H. O. and Moore, M. P. Ovari- York. an and paraovarian adenomatoid tumors. 2) Barwick, K. W. and Madri, J. A. An im- Am. ]. Obstet. Gynecol. 90, 388-394 (1964). munohistochemical study of adenomatoid tu- 15 \ Ferenczy, A., Fenoglio, J. and Richart, mors utilizing keratin and factor VIII anti- R. M. Observations on benign mesothelioma bodies. Evidence for a mesothelial origin. of the genital tract (adenomatoid tumor). Lab. Invest. 47, 276-280 (1982). A comparative ultrastructural study. Cancer 3) Said, J. W., Nash, G. and Lee, M. Immuno- 30, 244-260 (1972). peroxidase localization of keratin proteins, ]g\ Soderstrom, J. and Liedberg, C.-F. Malig- carcinoembryonic antigen, and factor VIII nant "adenomatoid" tumour of the epidi- in adenomatoid tumors: evidence for a dymis. Ada Pathol. Microbiol. Scand. 67, mesothelial derivation. Hum. Pathol. 13, 165-168 (1966). 1106-1108 (1982). 17) Akhtar, M., Reyes, F. and Young, I. Elasto- 4) Lehto, V.-P., Miettinen, M. and Virtanen, genesis in adenomatoid tumor. Histochemi- I. Adenomatoid tumor: immunohistological cal and ultrastructural observations. Cancer features suggesting a mesothelial origin. 37, 338-345 (1976). Virchows Arch. 42, 153-159 (1983). 18) Pinkus, G. S. and Kurtin, P. J. Epithelial 5) Urdiales-Viedma, M., Martos-Padilla, S. membrane antigen—a diagnostic discrimi- and Caballero-Morales, T. Adenomatoid tu- nant in surgical pathology: immunohisto- mors. Immunohistochemical study and histochemical profile in epithelial, mesenchymal, genesis. Arch. Pathol. Lab. Med. 109, 636- and hematopoietic neoplasms using paraffin 638 (1985). sections and monoclonal antibodies. Hum. 6) Hartwick, R. W. J., Sringley, J. R., Burns, Pathol. 16, 929-940 (1985). B. and McCaughey, W. T. E. A clinico- 19) Bonetti, F., Chilosi, M., Loddo, G., Zamboni, pathologic review of 112 paratesticular tu- G., Pea, M. and Menestrina, F. Adenomatoid mors. Lab. Invest. 56, 30A (1987) (ab- tumor: immunohistochemical demonstration stract). of epithelial membrane antigen (EMA). 7) Stephenson, T. J. and Mills, P.M. Adeno- Pathologica 76, 15-19 (1984). matoid tumours: an immunohistochemical 20) Kabawat, S. E., Bast, R. C. Jr., Bhan, A. K., and ultrastructural appraisal of their histo- Welch, W. R., Knapp, R. C. and Colvin, genesis. /. Pathol. 148, 327-335 (1986). R. B. Tissue distribution of a coelomic- 8) Davy, C. L. and Tang, C.-K. Are all adeno- epithelium-related antigen recognized by the matoid tumors adenomatoid mesotheliomas? monoclonal antibody OC 125. Int. J. Gyne- Hum. Pathol. 12, 360-369 (1981). col. Pathol. 2, 275-285 (1983). 9) Bell, D. A. and Flotte, T. J. Factor VIII 21) Bolen, J. W., Hammer, S. P. and McNutt, related antigen in adenomatoid tumors. M. A. Reactive and neoplastic serosal tissue. Implications for histogenesis. Cancer 50, A light-microscopic, ultrastructural, and im- 932-938 (1982). munocytochemical study. Am. J. Surg. 10) Murao, T., Funada, K., Kondo, M. and Pathol. 10, 34-^7 (1986). Okamoto, T. An immunoperoxidase study of 22) Katsube, Y., Mukai, K. and Silverberg, S. G. factor Vlll-related antigen in adenomatoid Cystic mesothelioma of the peritoneum. A tumors of the uterus. J. Karyocytopathology report of five cases and review of the litera- 20, 21-24 (1983) (in Japanese with English ture. Cancer 50, 1615-1622 (1982). abstract).

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