Monoclonal antibodies are currently used in the diagnosis of gynecologic
malignancies by way of immunohistochemical assays, serum assays, and in situ radiolocalization of
carcinoma lesions. Among them is MAb
B72.3, generated against a human
tumor-associated
antigen (TAG-72). Using immunohistochemical techniques, MAb
B72.3 has shown reactivity with 100 percent of common
epithelial ovarian carcinomas and
endometrial carcinomas and non-reactivity with normal adult tissues, with the exception of normal secretory endometrium.
B72.3 appears to be a valuable immunocytologic adjunct, with greater than 90 percent of effusions and fine-needle aspiration biopsies from gynecologic
carcinomas showing reactivity. Using a serum assay developed to detect the presence of the
TAG-72 antigen, 48 percent of patients with ovarian
carcinoma demonstrated TAG-72-positive sera versus 1 percent of control sera. 131I-labeled MAb
B72.3 IgG and gamma scanning have been used for the in situ detection of metastatic
carcinoma. Twelve of 15 patients with ovarian
carcinoma showed positive gamma scans, and approximately 80 percent of the lesions demonstrated specific localization of the antibody. These studies indicate the potential utility of MAb
B72.3 in the diagnosis of gynecologic
carcinoma.