Incidence, predictive factors and survival outcomes of incidental prostate cancer in patients who underwent radical cystectomy for bladder cancer.

Background: The aim of this study was to analyze the incidence, preoperative findings, pathological features and prognosis in patients with incidental prostate cancer (iPCa) detected at radical cystectomy (RC) for bladder cancer (BCa).

Methods: We retrospectively reviewed data of patients who underwent RC for BCa at our Institution between January 2005 and March 2018. Data regarding patient's history, preoperative digital rectal examination (DRE), total serum PSA level were collected from the chart review. Univariable and multivariable Cox regression models addressed the association of iPCa with recurrence-free survival (RFS) and overall survival (OS).

Results: We obtained a final study cohort of 177 patients. Median age was 69 years (IQR 42-89) and 80(45.2%) patients had iPCa. Patients with iPCa had higher age, preoperative PSA levels and a significant rate of suspicious DRE (all P<0.05). Four patients had BCR during a median follow-up of 28 months (IQR 6-159) and none died for prostate cancer. In multivariable analyses adjusted for age, bladder cancer BCa pT and pN stage and LVI the ten-years RFS and OS rates were not impacted by iPCa regardless of whether it is a clinically significant cancer or not (HR=1.25, 95% CI: 0.65-2.38, P=0.51 vs. HR=1.37, 95% CI: 0.71-2.64, P=0.35) (HR=1.04, 95% CI: 0.53-1.86, P=0.89 vs. HR=1.20, 95% CI: 0.22-6.72, P=0.83).

Conclusions: iPCa is quite common in our study group and most of cases are organ-confined and well differentiated. Regardless of clinical relevance, iPCa does not have an impact on survival outcomes as BCa is driving the prognosis of these patients.