Prognostic factors predicting successful response to sildenafil after radical cystoprostatectomy.

OBJECTIVES: To assess the efficacy and safety of sildenafil citrate in the management of erectile dysfunction (ED) following radical cystectomy (RC) and to define the different prognostic factors predicting the response to sildenafil in such a challenging group of patients.

MATERIAL AND METHODS: One hundred patients with ED following RC participated in an open-label, non-randomized, prospective, dose-escalation study. The median age of the patients was 53 years and the mean period after RC was 80.7 +/- 54.8 months. The study duration was 12 weeks, comprising a 4-week run-in period followed by two active treatment periods of 4 weeks each with 50 and 100 mg of sildenafil. Patients were assessed by means of the International Index of Erectile Function (IIEF) questionnaire at baseline and after each treatment period. At the end of the study, the Global Efficacy Assessment Question was used to evaluate treatment satisfaction. Factors affecting the patient's response to sildenafil were assessed by means of uni- and multivariate analysis.

RESULTS: The entire study group was suffering from severe ED at baseline, with a mean erectile function (EF) domain score of 6.5 +/- 0.93. EF scores improved to 12.2 +/- 7.76 and 18 +/- 10.3 with 50 and 100 mg of sildenafil, respectively. Sildenafil therapy significantly improved the ability of many patients to achieve and maintain an erection. The mean scores for question 3 of the IIEF were 1 +/- 0.14, 2.1 +/- 1.4 and 3 +/- 1.8 at baseline and with 50 and 100 mg of sildenafil, respectively, while the corresponding scores for question 4 were 1 +/- 0.10, 1.9 +/- 1.35 and 3 +/- 1.85. The satisfaction rate was 54%. The response was dose-dependent but the incidence of adverse effects increased from 6% with 50 mg of sildenafil to 34% with 100 mg. In univariate analysis, tumor histology and grade and postoperative partial tumescence were found to significantly impact the patient's response to sildenafil. In multivariate analysis, postoperative partial tumescence was the only independent predictive variable. CONCLUSIONS. Sildenafil was found to be a safe and satisfactory treatment for post-RC ED. The effect was dose-related. Patients with postoperative partial tumescence were the best responders.