Prevalence and Predicting Factors for Commonly Neglected Sexual Side Effects to External-Beam Radiation Therapy for Prostate Cancer

Introduction: Changes in sexual function other than erectile dysfunction are sparsely investigated after radiation therapy for prostate cancer. Aim: To investigate orgasmic dysfunction, urinary incontinence during sexual activity, changes in penile morphology, and sensory disturbances in the penis in patients with prostate cancer treated with external-beam radiation therapy (EBRT). Methods: In February 2015, men treated with EBRT at our center 3 months to 5 years previously (N = 519) received a study-specific questionnaire. This was developed from purpose-built questions and validated tools including the Erection Hardness Scale. All patients had received a radiation dose of 78 Gy. Androgen deprivation therapy was administered according to disease characteristics. Main Outcome Measures: Outcome measurements were prevalence rates and predictors of these side effects as identified by multivariate logistic regression analyses. Results: One hundred nine patients were eligible (sexually active and had completed androgen deprivation therapy) for inclusion. Twenty-four percent reported anorgasmia, 44% reported a decreased intensity of their orgasms, and 40% reported that the time it took to reach orgasm had increased. Eleven percent reported anejaculation. Fifteen percent reported orgasm-associated pain. Only 4% reported urinary incontinence during sexual activity. Subjective penile length loss in excess of 1 cm was reported by 42%. Twelve percent reported an altered curvature of their penis after EBRT. Six percent reported painful erections. Twenty-seven percent reported decreased sensitivity in the penis after EBRT, 2% reported a cold sensation, and 2% reported paresthesia. Increasing time since final treatment increased the risk of penile sensory disturbances (odds ratio = 1.05; P = .028). Conclusion: Orgasmic dysfunction, changes in penile morphology, and sensory disturbances in the penis are common side effects of ERBT. Patients should be properly informed of the occurrence of these side effects before deciding which treatment to pursue.