Density distribution and immunological reactivity of tumor cells from peritoneal effusions of patients with ovarian neoplasms.

Ascitic samples from 19 patients with primary ovarian non-mucinous carcinomas, three with Krukenberg tumors and eight with noncancerous peritoneal effusions were studied by conventional cytology and immunocytochemical staining. Density gradient centrifugation was applied to fractionate ascitic fluid cells. The enrichment of cell types by this method facilitated their cytomorphological characterization and identification of neoplastic cell subpopulations existing in peritoneal effusions. Immunophenotypic studies of cells were made using monoclonal antibodies (mAbs) against ovarian carcinoma-associated antigens (OC 125, 10B, 8C) and carcino-embryonic antigen (CEA). Non-specific cross-reacting antigen (NCA) was applied as a marker for granulocytes which often accompany peritoneal effusions. Our results indicated that immunofluorescence (IF) staining contributed to the distinction between the primary and secondary ovarian carcinomas. Density gradient centrifugation appeared to be a useful method for separation of mesothelial cells.