Efficacy of Tadalafil in Penile Rehabilitation Started Before Nerve-Sparing Robot-Assisted Radical Prostatectomy: A Double-Blind Pilot Study

Abstract

Abstract Background Despite the widespread practice of nerve-sparing robot-assisted radical prostatectomy (nsRARP) for the treatment of localized prostate cancer (PCa), erectile dysfunction remains a significant sequela of radical prostatectomy. Aim This study aimed to compare the efficacy of tadalafil 5 mg once daily for erectile function recovery in patients who underwent nsRARP according to the timing of rehabilitation initiation. Methods In this double-blind, prospective pilot study, a total of 41 patients who underwent nsRARP were randomly assigned into 2 groups according to the timing of rehabilitation initiation. In the preRARP group (n = 20), tadalafil was started 2 weeks before nsRARP, and in the postRARP group (n = 21), it was started 4 weeks after nsRARP. Erectile function recovery after nsRARP was defined as an International Index of Erectile Function (IIEF-5) score of ≥17. Outcomes The measures of EF recovery were the changes in IIEF-5 score. Results The rate of erectile function recovery at 12-month follow-up was 80.0% and 71.4% in the preRARP and postRARP groups, respectively. The mean differences between baseline and postoperative IIEF-5 scores at 1-, 3-, 6-, and 12-month follow-up were −11.7 ± 3.2, −7.4 ± 3.2, −5.6 ± 1.5, and −4.1 ± 1.1 in the preRARP group and −14.7 ± 4.7, −12.0 ± 5.0, −9.7 ± 3.9, and −6.0 ± 3.1 in the postRARP group, respectively (1-month, P = .259; 3-months, P = .077; 6-months, P = .014; 12-months, P = .007). Clinical implications Preoperative tadalafil 5 mg once a day could be used effectively and safely as a strategy for penile rehabilitation after nsRARP. Strengths and Limitations This study is the first prospective trial of penile rehabilitation with tadalafil 5 mg once a day prior to nsRARP. This is a pilot study with the limitations of a small sample; further and large-scale studies with multiple cohorts, such as an untreated control group and an early immediate rehabilitation group for EF recovery, are needed. Conclusion This study suggests that preoperative penile rehabilitation using tadalafil may lead to better erectile function recovery than postoperative penile rehabilitation using tadalafil.