Ovarian neoplasms of the thecoma-fibroma group. ImmunohistochemicaI stain for inhibin, CD 99, Melan A, CD 117

Hippokratia 2002, 6(1):3-10

A Kostopoulou, S Angelidou, M Leontsini


Ovarian neoplasms of the thecoma-fibroma group constitute an important part of sex cord-stromal tumors. They rarely occur in extraovarian sites. In recent years, sex cord-stromal neoplasms have been investigated by the use of several new immunohistochemical markers. The aim of the present study is to examine immunohistochemically ovarian tumors of the thecoma-fibroma group and the potential use of several markers for diagnostically problematic cases. Eighteen neoplasms of the thecoma-fibroma group from the archives of our laboratory were examined with immunohistochemical stains for inhibin a, CD 99, Melan A, COl17 (c-kit). Several tumors that are considered in the differential diagnosis were examined in comparison: leiomyomas, stromal tumors of the gastrointestinal tract, fibromatoses. Immunohistochemical stain for inhibin a was positive in 67% of tumors of the thecomafibroma group. CD 99 stain was positive in 39%. Stain for CD 117 (c-kit) was negative in the above neoplasms, while it was positive in GISTs. Immunohistochemi­cal stain for Al03 was positive mainly in sclerosing stromal tumors. In conclusion, the immunohistochemical stain for inhibin a and the negative stain for C0117 may help in the differential diagnosis of problematic cases of the above group. Immunohistochemical stain for AI03 may help in the diagnosis of sclerosing stromal tumors.