Increased upper and lower tract urothelial carcinoma in patients with end-stage renal disease: a nationwide cohort study in Taiwan during 1997-2008.

Background: Urothelial cancer (UC) is the leading cancer of patients with end-stage renal disease (ESRD) in Taiwan. The aims of this study were to explore the time trends of UC incidences and propose possible etiologic factors.
Methods: Abstracting from the National Health Insurance Research Database (NHIRD), there were 90,477 newly diagnosed cases of ESRD between 1997 and 2008 covering the patients aged 40-85. Among them, 2,708 had developed UC after diagnosis of ESRD. The CIR40-85 (cumulative incidence rate) of upper tract UC (UTUC) and lower tract UC (LTUC) were calculated for ESRD patients and general population, as well as SIR40-85 (standardized incidence ratio) for comparison.
Results: Female ESRD patients were found to have 9-18 times of elevated risks of UC, while those of males were increased up to 4-14 times. The time trends of CIR40-84 and SIR40-84 of UTUC in females appear to decline after calendar year 2000. These trends may be related to AA associated herbal products after 1998.
Conclusions: Patients with ESRD are at increased risks for both LTUC and UTUC in Taiwan. We hypothesize that the time trends associate with the consumption of aristolochic acid in Chinese herbal products (female predominant).