Immunoexpression of inhibin alpha subunit, inhibin/activin betaA subunit and CD99 in ovarian tumors.
OBJECTIVE
Anti-inhibin alpha and inhibin/activin betaA subunit and anti-CD99 monoclonal antibodies (mAbs) have recently been demonstrated to be able to label ovarian granulosa cells; thus, they may be of value in the diagnosis of granulosa cell tumors. The present study aimed to determine what combination of these mAbs may be useful for the differential diagnosis of sex cord-stromal tumors of ovary.


METHODS
Immunohistochemical analyses with anti-inhibin alpha and inhibin/activin betaA subunit antibody and anti-CD99 mAb were performed on 42 ovarian tumors, including sex cord-stromal tumors (29), ovarian epithelial cancers (10), and Krukenberg tumors (3).


RESULTS
All sex cord-stromal tumors were positive for inhibin alpha subunit, and 17 cases (58.6%) of sex cord-stromal tumors were immunoreactive for inhibin/activin betaA subunit. Epithelial tumors and Krukenberg tumors were all negative for inhibin/activin betaA subunit except mucinous carcinoma, which showed strong cytoplasmic immunoreactivity. All sex cord-stromal tumors except one granulosa cell tumor showed membranous staining for CD99. A case of serous carcinoma and a case of mucinous carcinoma were positive for CD99, and the remaining epithelial tumors and Krukenberg tumor were all negative for CD99.


CONCLUSIONS
The results of immunohistochemical analysis, together with literature review, suggest that inhibin alpha subunit may be a useful diagnostic marker for sex cord-stromal tumor of the ovary. In addition, anti-CD99 antibody may be useful for the differential diagnosis between ovarian tumors. Inhibin/activin betaA subunit has a limited usefulness in the differential diagnosis of ovarian tumor because of its wider immunoreactivity for both sex cord-stromal tumors and mucinous carcinomas. The differential diagnosis of sex cord-stromal tumors of the ovary would be better made with a combined use of both anti-inhibin alpha subunit and anti-CD99 mAbs.
Choi
Y L
YL
Department of Diagnostic Pathology, Samsung Medical Center, Kangnam-ku, Seoul, Korea.
Kim
H S
HS
Ahn
G
G
D000071443:12E7 Antigen; D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000032:analysis*; D002277:Carcinoma / Q000473:pathology*; D018269:Carcinoma, Endometrioid / Q000473:pathology; D015815:Cell Adhesion Molecules / Q000032:analysis*; D005260:Female; D005350:Fibroma / Q000473:pathology; D006106:Granulosa Cell Tumor / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D028322:Inhibin-beta Subunits; D007265:Inhibins / Q000032:analysis*; D007725:Krukenberg Tumor / Q000473:pathology*; D007984:Leydig Cell Tumor / Q000473:pathology; D010051:Ovarian Neoplasms / Q000473:pathology*; D010455:Peptides / Q000032:analysis*; D018312:Sex Cord-Gonadal Stromal Tumors / Q000473:pathology*; D013798:Thecoma / Q000473:pathology
D000071443:12E7 Antigen; D000911:Antibodies, Monoclonal; D015703:Antigens, CD; C061828:CD99 protein, human; D015815:Cell Adhesion Molecules; D010455:Peptides; C103008:inhibin beta A subunit; C094377:inhibin-alpha subunit; D007265:Inhibins; D028322:Inhibin-beta Subunits