The specific red cell adherence test in transitional cell carcinoma of the bladder before and after radiotherapy in patients with blood group A.

Serial formalin-fixed specimens of bladder tumors before and after irradiation from 19 patients with blood group A were tested for the presence or absence of antigen by the specific red cell adherence test. All patients had at least grade B transitional cell cancer of the bladder. The specific red cell adherence test was negative before radiotherapy in 9 patients, 4 of whom (44 per cent) had positive tests after treatment. However, the test was positive before radiotherapy in 10 patients (56 per cent) and became negative after radiotherapy in only 1. Of the patients 47 per cent had tumors that were positive for specific red cell adherence before and after radiotherapy, and 26 per cent had tumors that were consistently negative for antigen.