Do Phosphodiesterase Type 5 Inhibitors Increase the Risk of Biochemical Recurrence After Radical Prostatectomy?

Purpose:There have been conflicting studies on the association between phosphodiesterase type 5 inhibitor (PDE5i) use and biochemical recurrence (BCR) following radical prostatectomy (RP). Our aim was to determine whether PDE5i drug exposure after RP increases the risk of BCR in patients undergoing RP.Materials and Methods:An institutional database of prostate cancer patients treated between January 2009 and December 2020 was reviewed. BCR was defined as 2 PSA measurements greater than 0.1 ng/mL. PDE5i exposure was defined using a 0 to 3 scale, with 0 representing never use, 1 sometimes use, 2 regularly use, and 3 routinely use. The risk of BCR with any PDE5i exposure, the quantity of exposure, and the duration of PDE5i exposure were assessed by multivariable Cox proportional hazards models.Results:The sample size included 4630 patients to be analyzed, with 776 patients having BCR. The median follow-up for patients without BCR was 27 (IQR 12, 49) months. Eighty-nine percent reported taking a PDE5i at any time during the first 12 months after RP, and 60% reported doing so for 6 or more months during the year after RP. There was no evidence of an increase in the risk of BCR associated with any PDE5i use (HR 1.05, 95% CI 0.84, 1.31, P = .7) or duration of PDE5i use in the first year (HR 0.98 per 1 month duration, 95% CI 0.96, 1.00, P = .055). Baseline oncologic risk was lower in patients using PDE5i, but differences between groups were small, suggesting that residual confounding is unlikely to obscure any causal association with BCR.Conclusions:Prescription of PDE5i to men after RP can be based exclusively on quality of life considerations. Patients receiving PDE5is can be reassured that their use does not increase the risk of BCR.