Long-Term Prostate Cancer Side Effects Similar With Surgery, Radiation

Men treated for their localized prostate cancer have been found to have similar long-term side effects regardless of treatment type, a new study says. Men had similar levels of urinary incontinence, erectile dysfunction, and bowel urgency 15 years after treatment whether they were treated with surgery or radiation therapy.

Micrograph showing prostatic acinar adenocarcinoma; Gleason pattern 4; H&E stain; source: Nephron, Wikimedia Commons

Compared with radiotherapy, radical prostatectomy increased the odds of erectile dysfunction and urinary incontinence 2 and 5 years post-treatment. Compared with surgery, radiotherapy was associated with a higher chance of having bowel dysfunction at 2 and 5 years.

Overall, the extent of decline of sexual, urinary, and bowel function evened out by year 15. The study was published in the New England Journal of Medicine.

“While the data did reveal convergence in patient-reported outcomes at 15 years, the data also showed that, regardless of treatment choice, the risk of suffering functional decline was considerable,” said Matthew J. Resnick, MD, instructor in urologic surgery at Vanderbilt University Medical Center and lead author of the study.

While previous studies have compared patient outcomes between prostatectomy and radiotherapy in the short and midterm, little is known about long-term outcomes of these two approaches.

To assess the long-term effects of localized prostate cancer treatment, Resnick, David F. Penson, MD, and colleagues analyzed the Prostate Cancer Outcomes Study (PCOS). The study followed 3,533 men with prostate cancer, diagnosed in 1994 and 1995, who underwent either surgery or definitive radiation therapy within a year of their diagnosis. The final analysis included 1,655 men (between the ages of 55 and 74 at initial diagnosis) with localized prostate cancer-1,164 received surgery and 491 underwent radiotherapy.

“The goal of the PCOS was to follow these men throughout their survivorship experience,” said Resnick. “As the life expectancy for men with the disease lengthened, we sought to study the long-term effects of their remote prostate cancer treatments.”

As the median life expectancy after treatment for prostate cancer is 13.8 years, a long-term analysis to understand the long-term outcomes for men choosing between radiotherapy and surgery is important, state the authors.

Fifteen years post-diagnosis, 322 men (27.7%) who opted for a prostatectomy and 247 men (50.3%) who opted for radiation therapy had died.

At 2 years, those in the prostatectomy group were more than six times more likely to have urinary incontinence compared with the radiotherapy group. At 5 years, those who had a prostatectomy were still more likely to have urinary incontinence; the group was five times more likely to have worse urinary function compared with those who had radiotherapy.

Sexual dysfunction was also more likely at both year 2 and 5 in the prostatectomy group compared with the radiation therapy group.

In contrast, bowel urgency was more likely at both 2 and 5 years in those patients who were treated with radiation therapy compared with those who had surgery.

At 15 years, all of these significant differences disappeared for all of the functions, but absolute number differences remained. In the prostatectomy and radiotherapy groups, urinary incontinence was 18.3% vs 9.4%, respectively; erectile dysfunction was 87% vs 93.9%, respectively; and bowel urgency was 21.9% vs 35.8%, respectively.

Advanced age certainly contributes to the bowel, urinary, and sexual functions studied here. But, case-control studies by the PCOS researchers did show that prostate cancer patients had worse 5-year outcomes compared with their same-age counterparts who did not have prostate cancer.

One limitation of the study is that there may be differences between both the surgical approaches and radiotherapy approaches used now and those used 18 years ago. “We have seen improvements in technology over the past 15 years, including robotic surgery and image-modulated radiotherapy, that may indeed improve the outcomes for men undergoing therapy today,” Resnick acknowledged. As survival and quality-of-life data surrounding active surveillance programs mature, the ability to counsel men with newly diagnosed prostate cancer will be significantly enhanced, Resnick added.

More long-term, detailed studies are particularly important because the decision to treat and the type of treatment is unique for each patient.

“Prostate cancer remains a prime example of the need for shared decision-making, and it is our hope that these data, among others, will foster meaningful discussions between patients and their physicians, with the goal of aligning patient expectations and treatment outcomes,” said Resnick.