P53 ACCUMULATION AND C-MYC OVER-EXPRESSIO N IN BLADDER-CANCER

Carcinogenesis results from irreversible altrations of the physiologic al balance between protooncogenes and tumor suppressor genes. In this study alterations of the c-myc oncogene and the p53 tumor suppressor g ene during development and progression of bladder cancer were simultan eously investigated. 185 paraffine embedded urothelial specimens were examined. Normal urothelium yielded no alterations. P53 accumulation w as rare in low grade papillary tumors (6%), but c-myc overexpression w as present in 61%. I 19% of the dysplasia specimens p53 accumulation w as detected, while c-myc overexpression was observed in only 5%. Also in carcinoma in situ c-myc overexpression (18%) was less frequent as c ompared to p53 accumulation (31%). In Ta G2-4 tumors and T1 tumors the incidence of p53 accumulation was similar and slightly lower than in muscle invasive tumors. C-myc overexpression in appr. 60% of the speci mens was observed in Ta G2-4, T1 and T2-4 tumors. The simultaneous ana lysis of both genes yielded specific patterns for the different tumor stages. Uni- and multivariate analysis of various prognostic factors i n patients with superficial bladder tumors demonstrated a significant correlation between multifocal tumors, p53 accumulation and tumor prog ression (p < 0.001). Therefore, the detection of p53 accumulation migh t be of relevance for the treatment of these patients.