Basement membrane material in ovarian clear cell carcinoma: Correlation with growth pattern and nuclear grade

Stromal hyalinization in ovarian clear cell, carcinomas has been suggested to be caused by deposition of basement membrane (BM) material, but the biol ogical and diagnostic significance of this finding remains unknown. The dis tribution of BM material in 17 primary ovarian clear cell carcinomas was ex amined semiquantitatively using hematoxylin and eosin-stained sections and immunohistochemistry with antibodies to laminin and type IV collagen. For c omparison, other surface epithelial tumors, including 8 serous tumors of lo w malignant potential, 10 serous adenocarcinomas, 6 mucinous tumors of low malignant potential, 5 mucinous adenocarcinomas, 6 endometrioid carcinomas, 4 Brenner tumors, 1 transitional cell carcinoma, and 3 undifferentiated ca rcinomas, were examined. Stromal hyalinization was found in all 17 clear ce ll carcinomas and was immunoreactive for type IV collagen and laminin. Othe r types of surface epithelial tumor lacked these findings. In clear cell ca rcinoma, areas showing a papillary pattern tended to show abundant depositi on regardless of nuclear grade, whereas in solid, tubular, or cystic areas, the deposition was more prominent in areas showing high-nuclear-grade feat ures (grade 2 and 3) than in areas with low-nuclear-grade features (grade 1 ). Dense deposition of BM material recognized as stromal hyalinization on h ematoxylin and eosin-stained sections in primary ovarian clear cell carcino ma is a characteristic feature that is not seen in other ovarian surface ep ithelial tumors. This matrix production correlates with high-nuclear-grade features and papillary growth pattern.