Blood group antigen expression in frozen sections of presenting bladder cancer: 3-year prospective follow-up of prognostic value.

Blood group antigen (BGA) expression was studied on frozen sections from the initial, presenting, transitional cell bladder cancers of 73 patients. Clinical follow-up was prospective and, after 3 years, 59 patients were available for assessment. Of 32 tumours that retained substantial BGA (BGA+ and BGA +/- ), 11 progressed. Of 27 tumours with less than 5% or undetectable BGA expression (BGA-), 14 did not progress. Of 24 pTa tumours, 17 had substantial BGA expression and 7 were BGA-; 5 patients progressed, 4 substantially BGA positive and 1 BGA-, all to category pT1; 15 tumours were category pT1, 7 substantially BGA positive and 8 BGA-; 7 patients progressed, 1 substantially BGA positive and 6 BGA-, all of whom died from bladder cancer; 20 were pT2 or deeper, 8 substantially BGA positive and 12 BGA-; 12 patients progressed, 6 substantially BGA positive and 6 BGA-, all of whom died from bladder cancer. Despite improved understanding of the biochemistry and techniques of detection of BGA, these results preclude the use of BGA determination as a guide to prognosis in individual transitional cell carcinoma, whether used alone or in combination with pT category.