Histogenetic Consideration of Ovarian Sex Cord-stromal Tumors Analyzed by Expression Pattern of Cytokeratins, Vimentin, and Laminin: Correlation Studies with Human Gonads

Abstract

A total of 30 sex cord-stromal tumors including 9 adult type and 5 juvenile type granulosa cell tumors (GCTs), 4 Sertoli-Leydig cell tumors (SLTs), 1 gynandroblastoma, 5 thecomas, 2 fibromas and 3 sclerosing stromal tumors were immunohistochemically evaluated by means of cytokeratins of different molecular weight, vimentin and laminin with regard to the histogenesis of these tumors and to the embryogenesis of the sex cord and stroma of developing gonads. For comparison, 7 embryonic gonads, 9 fetal and 9 adult ovaries, 14 fetal and 5 postnatal testes, and 1 gonadoblastoma were also examined. The coelomic epithelium of all gonads were positive for both cytokeratins (CAM 5.2 and AE1) and vimentin. In fetal ovaries, the granulosa cells of primordial follicles express low molecular weight cytokeratins only and those cells of more maturing follicles did not express any cytokeratin or vimentin. In adult ovaries, the granulosa cells of primordial follicles coexpressed low molecular weight cytokeratins and vimentin, but those cells of more maturing follicles expressed vimentin only. In fetal testes before 20 weeks gestational age, the Sertoli and Leydig cells did not express any cytokeratins and vimentin. After that time, both cells expressed vimentin only throughout life. The rete ovarii and rete testis from fetal to adult life coexpressed both low molecular weight cytokeratins and vimentin. The rete ovarii in all ages and rete testis in prenatal and childhood ages were surrounded by the laminin-positive basement membrane, however, the rete testis in adult were not. In neoplasia, the GCTs, thecomas, fibromas, and sclerosing stromal tumors expressed vimentin only.(ABSTRACT TRUNCATED AT 250 WORDS)