New malignancies following cancer of the urinary bladder: analysis of German cancer registry data.

This analysis aimed at occurrence and distribution patterns of new malignancies following bladder cancer. Standardised incidence ratios (SIRs) were calculated for two German population-based cancer registries of North Rhine-Westphalia (NRW) and Saarland to access risks for subsequent primaries. An elevated risk for secondary cancer of any site but urothelium was observed in NRW men [SIR 1.35, 95% confidence interval (CI) 1.22-1.49]. The corresponding risk in Saarland was not significantly elevated (SIR 1.06, 95% CI 0.97-1.15). In data of both registries excess risks were observed for cancer of the respiratory tract (SIR 1.54, CI 1.23-1.89 in NRW men) and the prostate (SIR 1.91, 95% CI 1.61-2.24 in NRW; SIR 1.25, 95% CI 1.07-1.45 in Saarland). Common risk factors and incidental findings during follow-up care of bladder cancer patients might explain most of the observed patterns. In addition SIRs were throughout particular high for subsequent cancer of the renal pelvis and the ureter due to pathological characteristics of urothelial neoplasms.