Patient-reported sexual outcomes and potency following proton therapy for the management of prostate cancer.

Abstract

160 Background: The present study investigates sexual outcomes and potency rates in men treated with proton therapy for prostate cancer. Methods: Between 2006 and 2010, 1063 men were treated with proton therapy alone (no androgen deprivation therapy) for prostate cancer at University of Florida on an IRB approved outcomes tracking protocol. 99% of men were treated with 78-82 Gy (RBE). The expanded prostate index composite (EPIC) was collected prior to treatment and every 6-12 months after treatment. Potency was defined by question 59 of the EPIC, “How would you describe the usual Quality of your erections during the last 4 weeks”, where an answer of “firm enough for intercourse” was considered potent, while any other answer was considered “impotent”. Results: The EPIC was answered by 97%, 89%, 88%, and 84% at baseline, 6 months, 1 year, and 2 years after treatment. The median sexual summary (SS), sexual function (SF), sexual bother (SB) scores and potency over time are listed in the Table. A restricted analysis of SS, SF, SB and potency rates adjusted to baseline sexual score of 100 (best score) or potency is also included in the Table. Multiple logistic regression of 2 year impotency rate showed that age (<65 vs >=65, p=0.004) and baseline SS score (<68 vs68-99 vs100, p<0.0001) were significant prognostic factors. Among men with baseline potency (n=687), two years following treatment potency rates were 48% if the patient had baseline SS score of <=67 , 68% if the patient had a baseline SS score of 68 to 99 and 84% if their SS score at baseline was 100. Among just men with baseline SS of 100 (n=119), 87% of those age <65 were potent at 2 years, while 78% men age>=65 were potent at 2 years. Conclusions: Although sexual scores and potency decline following proton therapy, men with excellent baseline sexual function have very high rates of potency 2 years following treatment. Longer follow-up is needed. [Table: see text]