Phosphodiesterase Type 5 Inhibitors and the Risk of Melanoma Skin Cancer

Abstract

BackgroundThe association between phosphodiesterase type 5 inhibitors (PDE5-Is), drugs used in the treatment of erectile dysfunction (ED), and melanoma skin cancer is controversial. ObjectiveTo assess whether the use of PDE5-Is is associated with an increased risk of melanoma skin cancer. Design, setting, and participantsUsing the UK Clinical Practice Research Datalink, we assembled a cohort of men newly diagnosed with ED between 1998 and 2014 and followed until 2015. PDE5-I exposure was considered as a time-varying variable lagged by 1 yr for latency purposes. Outcome measurements and statistical analysisCox proportional hazards models were used to estimate adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) of incident melanoma associated with PDE5-I use overall and by number of prescriptions and pills received. Identical analyses were conducted for basal and squamous cell carcinoma, two cancers for which PDE5-related pathways are not thought to be involved. Results and limitationsThe cohort included 142 983 patients, of whom 440 were newly diagnosed with melanoma during follow-up (rate: 63.0 per 100 000 person-years). Compared with nonuse, PDE5-I use was not associated with an overall increased risk of melanoma (rates: 66.7 vs 54.1 per 100 000 person-years; HR: 1.18; 95% CI, 0.95–1.47). The risk was significantly increased among those who had received seven or more prescriptions and ≥25 pills (HR: 1.30 [95% CI, 1.01–1.69] and 1.34 [95% CI, 1.04–1.72], respectively). In contrast, there was no overall association with basal and squamous cell carcinoma, with an unclear association with numbers of prescriptions and pills received. ConclusionsThe use of PDE5-Is was not associated with an overall increased risk of melanoma skin cancer. The increased risks observed in the highest prescription and pill categories require further validation. Patient summaryIn this study, the use of phosphodiesterase type 5 inhibitors was not associated with an increased risk of melanoma skin cancer.