Studies of monoclonal antibody bl2-10d1 as a marker for the detection of the urothelial origin of tumors

Abstract

Background. In previous studies, the authors demonstrated the value of the monoclonal antibody (MoAb) BL2‐10D1 in identifying malignant transitional cells. In this study, the authors evaluate the possible diagnostic value of a murine MoAb, BL2‐10D1, raised against human bladder cancer in the determination of the urothelial origin of metastases in a series of 29 patients with metastatic bladder or prostatic carcinoma. Methods. Using an immunoperoxidase method, bl2‐10d1 and anti‐prostate‐specific antigen (anti‐psa) reactivity were studied, using histologic sections from 18 pelvic lymph nodes and 4 other anatomic sites invaded by transitional cell cancer, and from 7 pelvic lymph nodes containing prostatic cancer. Results. All lymph nodes containing metastases of transitional cell carcinoma were positive with BL2‐10D1, whereas all metastases of prostatic cancer were negative; the four instances of distant urothelial metastases were positive with BL2‐10D1 MoAb. Conversely, anti‐PSA reacted only with prostatic metastases. Conclusion. Thus, MoAb BL2‐10D1 and anti‐PSA complement each other in the separation of cancers of prostatic and urothelial origin, and the BL2‐10D1 MoAb has potential usefulness in differentiating between urothelial carcinoma and prostate adenocarcinoma. In patients with bladder tumors of uncertain origin, BL2‐10D1 may be helpful in confirming that a tumor is a transitional cell carcinoma.