A possible association between transitional cell carcinoma of the bladder and HLA-class II antigens (HLA-DR and HLA-DQ) in a group of patients with TCC were investigated. DR2, DR4 and DQw3 with allelic frequencies of 33.3%, 53.3% and 50% respectively were the most common antigens expressed in patients. In the control group the highest frequencies belonged to DR2, DR4 and DQw2 antigens. We found a significant difference in the frequency of HLA-DQw3 between patient and control groups. No significant differences were found at DR loci.
