USE OF A MONOCLONAL-ANTIBODY (B72.3) AS AN IMMUNOCYTOCHEMICAL ADJUNCT TO DIAGNOSIS OF ADENOCARCINOMA IN HUMAN EFFUSIONS

Abstract

A monoclonal antibody (MAb), designated B72.3 was generated using membrane-enriched fractions of a metastatic human breast carcinoma as the immunogen. The reactive antigen, a novel MW 220,000 to 400,000 glycoprotein complex, can be detected in formalin-fixed, paraffin-embedded tissue sections of human breast and colon carcinomas, and not in a vaiety of normal adult human tissues. MAb B72.3 may be used as an adjunct for diagnosis of adenocarcinoma in cytological perparations of human effusions. Using the avidinbiotin complex method of immunoperoxidase staining and formalin-fixed, paraffin-embedded cell suspensions, MAb b27.3 detected adenocarcinoma cells in effusion from all of 21 patients with adenocarcinoma of the breast. No reactivity was demonstrated in any cell type in benign effusions from 24 patients without cancer or 13 patients with prior or extant cancer in other body sites; B72.3 showed no reactivity to leukemic or lymphomatous effusions, or apparent mesothelial cells from malignant effusions. MAb B72.3 also detected adenocarcinoma cells in cytological effusion specimens from 12 of 12 patients with adenocarcinoma of the lung and 16 of 16 patients with adenocarcinoma of the ovary. The immunocytochemical application of MAb B72.3 should now be considered as an adjunct in the discrimination of adenocarcinoma cell from reactive mesothelial cells in the cytological diagnosis of malignant effusions.