The Effects of Focal Therapy for Prostate Cancer on Sexual Function: A Combined Analysis of Three Prospective Trials

Background: Tissue preservation by means of focal therapy offers some men with clinically significant prostate cancer an alternative to standard care that appears to confer favourable genito-urinary outcomes. The precise estimates of these outcomes have so far been based on small series.

Objective: This analysis pools the sexual domain related patient reported outcomes from three prospective, registered studies that represent a range of inclusion criteria.

Design, setting, and participants: One-hundred and eighteen men with localised prostate cancer (prostate specific antigen ≤ 15ng/ml, Gleason ≤ 4+3, stage ≤ T3aN0M0) treated in a tissue-preserving manner using high intensity focused ultrasound from three registered studies were included. Data on International Index of Erectile Function (IIEF-5) scores and use of phosphodiesterase-5-inhibitors were collected at baseline, and 1 mo, 3 mo, 6 mo, 9 mo, and 12 mo postoperatively. The IIEF-15 total and individual domain scores were used to assess overall sexual function. Urinary function was assessed with the International Prostate Symptom Score (IPSS), IPSS quality-of-life, and UCLA-Expanded Prostate Cancer Index Composite continence questionnaires. General health status was derived by means of the Charlson score. Multiple linear regression was used to assess whether age, grade, stage, qualitative scores (IIEF, IPSS, Expanded Prostate Cancer Index Composite, Charlson), or focal therapy type duration were associated with IIEF-5 and IIEF-15 scores at 12 mo.

Results and limitations: Median age was 63 yr (interquartile range [IQR] 52-70 yr). Median IIEF-erectile score at baseline was 23 (IQR 11-28). This declined significantly to 9 (IQR 3-22, p<0.01) at 1 mo, but improved to 20 (IQR 9-29, p=0.30) at 1 yr posttreatment. Changes in total IIEF and other IIEF domains were only significantly different from preoperative values at 1 mo and 3 mo postoperatively. In the same period, the proportion of men using phosphodiesterase-5-inhibitors was 10% preoperatively, reaching 43% and 42% at 6 mo and 9 months before declining to 37% at 1 yr. The only baseline determinants of postoperative erectile function were total IIEF and IIEF-erectile function scores (p=0.002). The primary limitation of our study is the relatively short follow-up of 1 yr.

Conclusion: Men who received a range of tissue preserving therapies from the three pertinent studies experienced small decreases in total IIEF, erectile, and individual sexual domain scores that are not significantly different to those recorded at baseline. The only determinant of erectile dysfunction after tissue preserving therapy was preoperative erectile dysfunction status. Tissue preservation confers a high probability of maintaining erectile function that appears independent of all perioperative factors with the exception of baseline status.

Patient summary: In this report, the largest prospectively collected and published set of patients with erectile dysfunction outcomes post-focal therapy for prostate cancer, we have found a return to baseline International Index of Erectile Function-erectile and total International Index of Erectile Function scores by 6 mo post-focal therapy which was maintained at 1 yr, with the majority of patients not on any form of medical treatment for their erectile dysfunction at that point. Focal therapy may represent a suitable alternative for men of any age or comorbidity wishing to maintain erectile function.