ABSTRACT
Expression of blood group antigens A, B and H was studied in 6 cases with chronic cystitis, 31 cases with squamous cell carcinoma [S.C.C.], 13 cases with transitional cell carcinoma [T.C.C.], 3 cases with adenocarcinoma, 2 cases with undifferentiated carcinoma and 5 cases of normal urinary bladder epithelium as control-using the immunoperoxidase staining via peroxidase antiperoxidase [PAP] technique. It was found that the areas of chronic cystitis retained A, B and H antigens similar to be control [normal urinary bladder epithelium] while in patients with S.C.C., 55% of the patients with grade I tumours, 82% with grade II and 89% with grade III tumourse had loss of cell surface antigens and 29% of the cases expressed H-antigens in the areas of S.C.C. In patients with T.C.C., 50% of the patients with grade I tumours, 75% with grade II and all patients grade III tumours had loss of cell surface antigens and 38.5% of the cases demonstrated H-antigens in the areas of T.C.C. All cases of undifferentiated carcinoma had loss of cell surface antigens. In contrast, cases of adenocarcinoma showed loss of isoantigens in 2 cases of grade I and expressed them in grade II tumour. Sixty seven percent of the cases expressed H antigens in the areas of adenocarcinoma. The adjacent areas to carcinoma whether S.C.C. or T.C.C. were regaining the normal antigen and losing the H-antigen gradually as one goes from the micro-invasive area to areas of carcinoma in situ, dysplasia and back to normal epithelium. This study suggests that expression of A, B and H. blood group isoantigens in the urinary bladder carcinoma [S.C.C. or T.C.C.] is correlated to the grade of tumour and tends to be lost as the histological grade increase. Patients with blood group O were more susceptible to loss of blood group isoantigens. Further studies are recommended to correlate between A, B and H isoantigens with the prognosis