Urinary tuberculosis is associated with the development of urothelial carcinoma but not renal cell carcinoma: a nationwide cohort study in Taiwan

BACKGROUND: Obstructive uropathy and chronic urinary tract infection increase the risk of urinary tract cancer. Urinary tuberculosis (UTB) can cause chronic urinary tract inflammation, lead to obstructive uropathy, and potentially contribute to the development of urinary tract cancer. However, the association between UTB and urinary tract cancer has not been studied. METHODS: This study enrolled 135 142 tuberculosis (TB) cases (male, 69%) from a nationwide health insurance research database in Taiwan and investigated the risk factors for urinary tract cancer, with emphasis on a history of UTB. The incidence of urinary tract cancer in the general population without TB was also calculated for comparison. RESULTS: The TB patients had a mean age of 57.5±19.5 years. Of the 1287 UTB and 133 855 non-UTB patients, 15 (1.2%) and 396 (0.3%) developed urothelial carcinoma, respectively (P<0.001); and 2 (0.2%) and 96 (0.1%) developed renal cell carcinoma, respectively (P=0.240). Cox regression analysis revealed that age, male sex, end-stage renal disease, obstructive uropathy, arsenic intoxication, organ transplantation, and UTB (hazard ratio: 3.38 (2.01–5.69)) were independent risk factors for urothelial carcinoma. The hazard ratio of UTB was higher among female patients (5.26 (2.12–13.06)) than that among male patients (2.96 (1.57–5.60)). CONCLUSION: Urinary tuberculosis had a strong association with urothelial carcinoma, but not with renal cell carcinoma. In TB endemic areas, the urinary tract of TB patients should be scrutinised. It is also imperative that these patients be followed-up carefully in the post-treatment period, and urinalysis, ultrasonography or endoscopy should be an integral part of the follow-up.