Sexual function is an important concern in men receiving intensity modulated radiation therapy (IMRT) for prostate cancer. Our aim was to study the impact of IMRT and androgen deprivation therapy (ADT) on sexual function over time and to report the effectiveness of sexual medications or aids.

A total of 179 men, median age 69, received definitive IMRT for prostate cancer and completed 2 surveys (Expanded Prostate Cancer Index Composite-26 and a sexual medicines/devices survey) for at least 2 time points. Surveys were prospectively collected at baseline (before all therapy), and 2, 6, 12, 18, and 24 months after IMRT. Median dose was 76 Gy to the prostate. ADT was administered to 59% of patients (median duration 5 months, initiated 2 months before IMRT). Global scores were generated for the Expanded Prostate Cancer Index Composite-26 questions. Longitudinal analysis was performed by constructing a generalized estimation equations model, and clinical variables were tested for association with global scores.

Overall, there was a significant decline in global sexual score through 2 years. Men receiving ADT had a lower sexual score at 2 and 6 months, but this difference disappeared at 24 months. Analysis of individual sexual symptoms showed no significant difference at 24 months except that men on ADT were less likely to be sexually active (P = .02); this difference was not observed for men receiving short-term ADT only. Longitudinal analysis revealed that duration of ADT was the only factor associated with global sexual score. Phosphodiesterase inhibitors were attempted by roughly half of all men, with 66% experiencing benefit, whereas other aids were attempted by roughly 5% of men.

Although ADT adversely affected short-term sexual function, there was no significant difference in global score and most sexual symptoms by 24 months. These data are useful for anticipatory guidance regarding expectations after IMRT.