Blood group antigens in epithelial tumours of the urinary bladder.

The occurrence of blood isoantigens, demonstrated using an immunofluorescence technique in urothelial tumours of 40 blood group A, B, or AB patients who had been treated and followed up during the years 1977-1983, has been compared with their histological grading and clinical course. In both of the 2 papillomas and 35 grade I papillocarcinomas, a positive expression of the relevant isoantigens could be demonstrated, while all of the 19 grade III papillocarcinomas just as the 22 anaplastic carcinomas always proved negative. In a group of 34 grade II papillocarcinomas, 21 of the tumours proved positive and 13 negative; with all tumours showing signs of invasiveness being always negative. Correlation of these results with the clinical courses of the disease did not exhibit such unequivocal results, even though, in a group of 7 patients who had died of a generalized urothelial carcinoma verified by post-mortem, all of the 19 examinations that have been performed proved, with the exception of one, to be negative. These results confirm the fact that identification of blood isoantigens may help to reach a more accurate prediction of the biological behaviour and prognosis of urothelial carcinomas, especially, among grade II papillocarcinomas since loss of the antigen expression appears to be related to the tumour's capacity of invading the mucous stroma.