Incidental prostate cancer in patients with bladder urothelial carcinoma: Comprehensive analysis of 1,476 radical cystoprostatectomy specimens

Purpose: We identified risk factors and determined the incidence and prognosis of incidental, clinically significant prostatic adenocarcinoma, prostatic urothelial carcinoma and HGPIN in patients treated with radical cystoprostatectomy for urothelial carcinoma of the bladder. Materials and Methods: We analyzed the records of 1,476 patients without a history of prostatic adenocarcinoma. We determined the incidence of clinically significant prostatic adenocarcinoma, prostatic urothelial carcinoma and HGPIN in the total cohort and in select patient subgroups. Prostatic urothelial carcinoma was stratified as prostatic stromal and prostatic urethral/duct involvement. Univariate and multivariate analyses were performed with multiple variables. Recurrence-free and overall survival rates were calculated. Median followup was 13.2 years. Results: Of the 1,476 patients 753 (51.0%) had cancer involving the prostate. Prostatic adenocarcinoma, clinically significant prostatic adenocarcinoma, prostatic urothelial carcinoma and HGPIN were present in 37.9%, 8.3%, 21.1% and 51.2% of patients, respectively. Of the 312 patients (21.1%) with prostatic urothelial carcinoma 163 (11.0%) had prostatic urethral/duct involvement only and 149 (10.1%) had prostatic stromal involvement. We identified risk factors for clinically significant prostatic adenocarcinoma, prostatic urothelial carcinoma and HGPIN but the absence of these risk factors did not rule out their presence. Ten-year overall survival in patients with no prostatic urothelial carcinoma, and prostatic urethral/duct and prostatic stromal involvement was 47.1%, 43.3% and 21.7%, respectively (p <0.001). No patient with clinically significant prostatic adenocarcinoma died of prostatic cancer. Conclusions: More than half of the patients undergoing radical cystoprostatectomy had cancer involving the prostate. Prostatic urothelial carcinoma, particularly with prostatic stromal involvement, was associated with a worse prognosis, while clinically significant prostatic adenocarcinoma did not alter survival. Preoperative clinical and histopathological risk factors are not reliable enough to accurately predict clinically significant prostatic adenocarcinoma and/or prostatic urothelial carcinoma.