De Novo Bladder Urothelial Neoplasm in Renal Transplant Recipients: A Retrospective, Multicentered Study

Background and Objectives: Renal transplant recipients (RTRs) have a 2- to 7-fold risk of developing a neoplasm compared to general population. Bladder urothelial neoplasms in this cohort has an incidence of 0.4-2%. Many reports describe a more aggressive behavior. The objective of this study is to describe oncologic characteristics of bladder urothelial neoplasms in RTRs and to evaluate its recurrence, progression, and survival rates. Methods: A retrospective multicentered study was performed evaluating all de novo bladder urothelial neoplasms cases in RTRs from 1988 to 2014. Descriptive statistical analysis and evaluation of recurrence, progression, and survival rates were performed. Results: A total of 28 de novo bladder transitional cell carcinomas (TCCs) were identified (incidence rate 0.64%). Cancer-specific survival rates were 100, 75, and 70% after 1, 5, and 10 years, respectively. Age at diagnosis superior to 60 years was found to be a statistically significant variable for recurrence risk. Progression rate was 14%. Presence of CIS was significantly associated with progression. All cancer-specific deaths were in the high-risk group and all were progressions from non-muscle invasive to muscle invasive bladder cancer. Conclusions: Bladder urothelial neoplasms following renal transplant is associated with a trend toward worst prognosis. Early aggressive treatments, such as early radical cystectomy, might be advisable to reduce cancer-specific deaths.