THE MONOCLONAL-ANTIBODY 7E(12)H(12) CAN DIFFERENTIATE PRIMARY ADENOCARCINOMA OF THE BLADDER AND PROSTATE

Objective To determine if the monoclonal antibody 7E(12)H(12), which r eacts with a 40 kDa protein in normal human enterocytes and has been s hown to be a marker for intestinal metaplasia and adenocarcinoma arisi ng in the bladder, could assist in distinguishing prostatic, urachal a nd vesical adenocarcinoma, using a sensitive immunohistochemical assay . Materials and methods Fifteen primary prostatic adenocarcinomas and five adenocarcinomas of the urinary bladder were selected for a retros pective evaluation, The monoclonal antibody 7E(12)H(12) (IgM isotype) was used in an immunoperoxidase assay to survey formalin-fixed, paraff in-embedded archival tissue specimens. Results All vesical adenocarcin omas reacted positively with the antibody, regardless of grade; none o f the 15 prostatic specimens reacted positively in either the benign o r malignant glandular epithelium. Conclusion The monoclonal antibody 7 E(12)H(12) can differentiate primary adenocarcinoma of the bladder fro m secondary adenocarcinoma arising in the prostate and may be a useful tool in diagnostic pathology.