REDUPLICATED BASAL LAMINA IN CLEAR-CELL CARCINOMA OF THE OVARY - AN IMMUNOHISTOCHEMICAL AND ELECTRON-MICROSCOPIC STUDY

Clear-cell carcinomas of the female genital tract are uncommon tumors that usually arise in the ovary, cervix, or vagina. The objectives of the present study were to examine the immunohistochemical and ultrastr uctural characteristics of 18 of these tumors and to determine whether any distinctive features were present at the different locations. The fine structure of the neoplastic cells was similar at the several sit es but there was a striking difference in the appearance of the basal lamina. Prominent reduplication of the basal lamina was seen in all 7 ovarian carcinomas, whereas it was mild in 3 and absent in 7 of the ce rvico-vaginal tumors. The distribution of eosinophilic hyaline materia l in hematoxylin/eosin sections and of immunohistochemical staining fo r type IV collagen and laminin correlated with the ultrastructural obs ervations. Reduplication of the basal lamina has been observed in a nu mber of epithelial neoplasms and viewed as a criterion of differentiat ion, but there is currently no evidence that its presence influences t he prognosis of clear-cell carcinomas of the ovary.