Immunohistological characterization of a monoclonal antibody (OV632) against epithelial ovarian carcinomas

A hybridoma cell line (OV632) producing monoclonal antibody against ovarian carcinomas was developed from the spleen cells of a mouse immunized with cystic fluid from a serous cystadenocarcinoma. Immunohistological studies in frozen sections showed that 22 out of 28 nonmucinous ovarian carcinomas, which included serous, endometrioid, clear cell, and undifferentiated tumours, reacted with this antibody. Three out of 7 mucinous ovarian carcinomas were positive, whereas only 7 out of 122 extra-genital malignant lesions, predominantly adenocarcinomas, were positive. The negative cases included 38 breast carcinomas and 24 colon carcinomas, tumours which are responsible for most of metastatic disease in the ovary. On the basis of these findings, the antibody OV632 is considered appropriate for histodiagnostic purposes as an aid in the distinction between primary and secondary ovarian cancer.