Robotic Surgery for Prostate Cancer has Lesser Impact on Sexual Function

Although use of robotic surgery for prostate cancer has surpassed open surgical procedures in number, the impact of this approach on patient quality of life has not been well-studied. To address this knowledge gap, a group of researchers compared quality of life indicators from two prior studies of patients with prostate cancer who had either robotic or open surgery and found that scores on sexual function were better for those who had the robotic procedure, yet comparative results for urinary function were not as conclusive.

The findings of the analysis were shared in a late-breaking abstract reported at the 2015 American Urological Association (AUA) Annual Meeting May 17 in New Orleans.

“In our study, we examined urinary and sexuality quality of life outcomes from two large cohort studies that were separated in time and dominated by a single technique,” says Brock O’Neil, MD, of the department of Urologic Surgery at the Vanderbilt University Medical Center. “Our hypothesis was that neither surgical approach would result in superior quality of life over the other.”

Currently most available quality of life data on robot-assisted, laparoscopic radical prostatectomy (RALP) and open radical prostatectomy (RRP), are from single surgeon/center reports, lack adequate risk-adjustment, or use limited information on patient-reported outcomes, O’Neil explained.

To gain a better comparative understanding of post-prostatectomy quality of life, researchers looked at data from two large, population-based, prospective cohort studies: the Prostate Cancer Outcomes Study (PCOS) conducted from 1994-1995 and the more recent Comparative Effectiveness Analysis of Surgery and Radiation (CEASAR) study which was carried out from 2011-2012. All PCOS patients had open surgery, and quality of life was assessed using the UCLA Prostate Cancer Index. The majority of men (78 percent) in CEASAR had the robotic procedure, and quality of life was measured using the Expanded Prostate Cancer Index Composite-26.

In order to account for differences in these tools, researchers identified four common measures of urinary incontinence, three of sexual function, and set modified domain summary scores on a scale of 0-100, with 100 indicating ideal function.

Differences between the groups were assessed at six and 12 months after surgery using multivariate linear regression. Covariate adjustment was used to control for sociodemographic and clinical pathologic features, including baseline urinary and sexual function.

Data were analyzed for 2,438 men across the two study cohorts, 1,505 of whom had RRP, and 933 had RALP. Among the men who underwent RRP, 1,243 were from the PCOS study and 262 were from the CEASAR study.

For the 74 percent of men with excellent urinary function scores (= 100) at baseline, those who underwent RALP had a mean quality of life score of 74.1 at six months versus 70.4 in the RRP group (a difference of 3.8 points); however, urinary continence scores were not significantly better at 12 months (78.7 vs 77.5, respectively, or a difference of 1.2 points).

Among the upper quartile of men who had with excellent baseline sexual function, the mean score after six months was 55.1 in the RALP group versus 44.9 in the RRP cohort, a difference of 10.2 points. Notably, and unlike the urinary continence scores, at 12 months, the sexual function score differential was sustained, with better scores in the robotic surgery group (61.4 vs 51.1, respectively, a 10.3-point difference).

In the lower quartile of men with reduced sexual function at baseline (score = 65) the mean score for those undergoing robotic surgery still had a statistically significant better score (45.9 vs 40.7, respectively (+5.2) which continued at 12 months, where mean scores were 3.3 points higher in the RALP group (49.0 vs 45.7, respectively).

“Sensitivity analysis, which compared robotic CEASAR vs open CEASAR, robotic CEASAR vs open PCOS, and open CEASAR vs open PCOS, provided consistent support for the sexual function outcomes and mixed support for urinary incontinence outcomes,” says O’Neil.

O’Neil noted that the study had a few limitations. Quality of life measures were used from two different scales, which were not previously psychometrically validated, and PDE5 inhibitors were not available during the PCOS enrollment period.

“Our study, using CEASAR and PCOS, which were performed more than a decade apart but having similar methodology, suggests that robotic surgery performs better than open surgery for sexual function and possibly urinary function, out to at least 12 months,” O’Neil concluded.

Longer follow-up is required to establish whether benefits persist beyond one year and to assess for differences in oncologic outcomes.

O'Neil B, Koyama T, Rudd J, et al. Evidence of superior quality of life after robotic prostatectomy: results from a population-based analysis. Presented at: AUA Annual Meeting; May 15-19, 2015; New Orleans, LA. Abstract PII-LBA5.