Challenges in Reporting the Effect of Radiotherapy on Erectile Function

Background: Erectile dysfunction (ED) is the most common side effect of prostate radiotherapy (RT), but reported rates over time and across modalities have varied widely. Aim: To evaluate the published literature between 2002 and 2018 for high quality data utilizing prospectively gathered patient-reported ED, and to summarize the challenges in reporting of RT-induced ED (RIED). Methods: A PubMed search and literature review was performed to identify articles describing rates of ED before and after definitive external beam RT or brachytherapy without androgen deprivation. Outcomes: Patient-reported ED, patient and treatment variables, and study follow-up constituted the main outcomes of this study. Results: 24 articles were identified, reporting RIED rates between 17% and 90%. Variables contributing to this range included patient, treatment, and study characteristics known to impact ED reporting. Clinical Implications: For future studies, we recommend the use of validated patient-reported questionnaires and reporting of baseline function and comorbidities, RT type and dose, and use of androgen deprivation therapy and erectile aids at the time of ED measurement. With sufficient follow-up to understand the late nature of RIED, these recommendations will improve comparison of results between studies and the applicability of results to patients undergoing pretreatment counseling regarding the risks of RIED. Strengths & Limitations: The literature search and formulation of results were based on a broad understanding of the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines and the literature, but because of the focus on data reporting, a comprehensive systematic review of all RIED literature was not performed. Conclusion: Reported rates of ED after RT vary widely due to differences in patients' baseline reported erectile function, age, comorbidities, and characteristics of the treatment delivered. The methodology of ED measurement has significant impact on the applicability and comparability of results to other studies and clinical practice. Copyright (C) 2020, International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.