A 5-year follow-up study of more than 2,000 U.S. men who received
prostate cancer treatment—radiation, surgery, or active surveillance—in
patients of all ages and ethnicities is creating a road map for the
future regarding long-term bowel, bladder, and sexual function in order
to clarify expectations and enable men to make informed choices about
care. This analysis was published by Hoffman et al in JAMA.
The CEASAR (Comparative Effectiveness Analysis of Surgery and
Radiation for Localized Prostate Cancer) study, coordinated by
Vanderbilt University Medical Center, is a multisite research study
conducting long-term follow-up on men who were diagnosed with localized
prostate cancer between 2011 and 2012.
“We are providing information about the side effects of different
treatments for prostate cancer that men and their providers can use to
make treatment decisions,” said senior author Daniel Barocas, MD, MPH,
Associate Professor and Vice Chair of Urology at Vanderbilt University
Medical Center. “However, we have only illuminated one facet of a
complex decision. There is more to a treatment decision than just the
side effects, the most obvious being the effectiveness of the treatment,
and that is something we hope to be able to demonstrate as we are now
funded to look at 10-year cancer outcomes.”
Treatment Types
Researchers studied 1,386 men who had favorable-risk prostate cancer
and another 619 men with unfavorable-risk prostate cancer to evaluate
the impact of their treatment decisions on urinary, sexual, and bowel
function over a 5-year period. The favorable-risk group chose either
active surveillance, nerve-sparing prostatectomy, external-beam
radiation therapy, and low–dose rate brachytherapy. The unfavorable-risk
disease group chose either prostatectomy or external-beam radiation
therapy plus androgen-deprivation therapy (ADT).
Sexual Outcomes
Men undergoing surgery experienced an immediate, sharp decline in
erectile function compared to other groups. However, on average, men
treated with prostatectomy improve with time, while those undergoing
radiation decline, so that sexual function differences between treatment
groups attenuated by 5 years. While the difference in sexual function
between surgery and radiation was still measurable in the
unfavorable-risk group, most men had such poor scores at 5 years that
the difference between treatments may not be clinically significant.
“For sexual function, all of the treatment options, even
surveillance, were associated with significant declines,” said Dr.
Barocas. “Indeed, the magnitude of decline over time within each
treatment group was larger than the magnitude of difference between
treatment groups at 5 years.”
“Whether you get surgery or radiation, there is a chance of reduced
erectile function,” he said. “While the time course is different for
surgery and radiation, our study shows that only about half of men
undergoing these treatments who had erections good enough for
intercourse before treatment will still have an erection good enough for
intercourse 5 years later. I have started using this sobering statistic
in patient counseling about treatment choice.”
Urinary and Bowel Function
In terms of urinary function, prostatectomy was associated with worse
incontinence compared to other treatments through 5 years for both the
favorable-risk and the unfavorable-risk groups. At 5 years, 10% to 16%
of men who had surgery reported a moderate or serious problem with
leakage, compared to 4% to 7% of men who had other treatments.
Men undergoing radiation reported worse urinary irritative and
obstructive symptoms within the first 6 to 12 months, particularly those
undergoing low–dose rate brachytherapy. However, these urinary symptoms
largely returned to baseline after 1 year. In addition, study authors
reported no clinically meaningful bowel function differences at the
5-year mark, suggesting that contemporary radiation therapy is
associated with less urinary and bowel toxicity than older forms of
radiation.
“If you look at the side-effect profile for external-beam radiation,
most of those men after 1 year have rebounded in terms of their urinary
and bowel function, which is a novel finding of our study,” said Dr.
Barocas said. “The brachytherapy patients have a more difficult time
with the urinary and bowel symptoms in that first year.”
For men with unfavorable-risk disease, external-beam radiation with
ADT was associated with low hormonal function scores at 6 months and
bowel function at 1 year, but these symptoms improved at later time
points. The men who received external-beam radiation with ADT also had
better sexual function at 5 years and incontinence at each time point
through 5 years than prostatectomy.
Study authors said, overall, the estimates of long-term bowel,
bladder, and sexual function after localized prostate cancer treatment
may clarify expectations and enable men to make informed choices about
care.