Study tracks long-term impact of prostate cancer treatment on urinary, sexual, and bowel function
A new study compared outcomes among prostate cancer patients treated with surgery versus radiotherapy. Differences in urinary, bowel, and sexual function were reported at short-term follow-up, but those differences were no longer significant 15 years after initial treatment.
This study followed 1,655 men age 55 to 74 years with localized prostate cancer who were enrolled in the Prostate Cancer Outcome Study. Among these men, 1,164 (70.3%) had undergone prostatectomy, while 491 (29.7%) had undergone radiotherapy. At the time of enrollment, the patients were asked to complete a survey about clinical and demographic issues and health-related quality of life. The men were contacted again at set times following treatment and were asked about clinical outcomes and disease-specific quality of life issues.
Men whose prostates had been surgically removed were significantly more likely to report urinary leakage at 2 years and 5 years than were those who received radiation therapy. However, at 15 years, the investigators found no significant difference in the adjusted odds of urinary incontinence. Nonetheless, patients in the surgery group were more likely to wear incontinence pads throughout the 15-year follow-up period. Men in the prostatectomy group were also significantly more likely than those in the radiotherapy group to report having problems with erectile dysfunction 2 years and 5 years after surgery.
"At the 2- and 5-year time points, men who underwent prostatectomy were more likely to suffer from urinary incontinence and erectile dysfunction than men who received radiation therapy," explained first author Matthew Resnick, MD, of Vanderbilt University Medical Center in Nashville, Tennessee. "While treatment-related differences were significant in the early years following treatment, those differences became far less pronounced over time." Despite early and intermediate-term data revealing treatment-dependent differences in patterns of sexual dysfunction, after 5 years both groups had a gradual decline in sexual function.
At 15 years, erectile dysfunction was nearly universal with 87% in the prostatectomy group and 93.9% in the radiotherapy group reporting sexual difficulties. Age may have played a role in the patients' waning sexual function.
Some patients also experienced problems with bowel function in the years following treatment. Those who were treated with radiotherapy had more problems in the short term. Men in the radiotherapy group reported significantly higher rates of bowel urgency than those in the prostatectomy group at 2 years and 5 years. However, at 15 years, despite absolute differences in the prevalence of bowel urgency between the two groups, the researchers found no significant difference in the odds of bowel urgency. Men who had been treated with radiotherapy were significantly more likely to report being bothered by bowel symptoms at both the 2-year and 15-year points.
"This study of 15-year outcomes represents a mature portrait of quality of life issues following prostate cancer treatment," said the senior study author David Penson, MD, MPH, also of Vanderbilt. This study was published in the New England Journal of Medicine (2013;368:436-445).