Specific red cell adherence: immunologic evaluation of random mucosal biopsies in carcinoma of the bladder.

We studied 103 random biopsies from patients with overt transitional cell carcinoma of the bladder for specific red cell adherence. We evaluated 62 random biopsies from patients whose primary tumors were positive for specific red cell adherence and 100 per cent of the biopsies in these patients also were positive for specific red cell adherence regardless of the pathologic finding in the random biopsy. We evaluated 41 random biopsies from patients whose primary bladder tumors were negative for specific red cell adherence and only 27 per cent of all biopsies in this group of patients were positive for specific red cell adherence. Thus, we found that in 92 of the 103 random biopsies (89 per cent) and specific red cell adherence of the biopsy agreed with that of the primary tumor. The loss of red cell antigens in random biopsies that are histologically normal may prove to be the earliest measureable changes of the malignant potential of the urothelium.