Understanding Functional Outcomes in Prostate Cancer

FROM JAMA

Men with localized prostate cancer face a number of treatment choices, including radical prostatectomy, radiotherapy with or without androgen deprivation therapy, and active surveillance. Understanding the likely functional outcomes of each treatment over time is important as most patients are expected to live at least 15 years after diagnosis.

New research published on January 23 in JAMA parses functional outcome results from a population-based study of men diagnosed with localized prostate cancer. For their research, Bashir Al Hussein Al Awamlh, MD, of Vanderbilt University in Nashville, Tennessee, and his colleagues looked at sexual function, urinary health, bowel function, hormonal function, and other outcomes in this cohort at 10 years' follow-up.

Among 2455 patients for whom 10-year data were available, 1877 were deemed at baseline to have a favorable prognosis (defined as cT1-cT2bN0M0, prostate-specific antigen level less than 20 ng/mL, and grade group 1-2), and 568 had unfavorable-prognosis prostate cancer (defined as cT2cN0M0, prostate-specific antigen level of 20-50 ng/mL, or grade group 3-5). Follow-up data were collected by questionnaire through February 1, 2022. The men in the study were all younger than 80 years, and three quarters of them were White.

At 10 years, outcomes differed based on the amount of time that had passed since diagnosis (they found different results at 3- and 5-year follow-ups, for example) and which treatment a patient received.

Among men with favorable prognoses at diagnosis, 20% underwent active surveillance for at least 1 year, while 56% received radical prostatectomy, 19% had external beam radiotherapy (EBRT) without ADT, and 5% had brachytherapy. Nearly a third of men originally opting for surveillance went on to undergo a therapeutic intervention by 10 years.

Dr Al Hussein Al Awamlh and his colleagues found that while 3- and 5-year follow-up studies in this cohort had shown declines in sexual function among men who underwent surgery compared with those who had radiation or active surveillance, by 10 years those differences had faded, with no clinically meaningful differences in sexual function scores between the surgery and surveillance groups. In an interview, Dr Al Hussein Al Awamlh said that this finding likely reflected mainly age-related declines in function across the study population — though it could also reflect declines after converting from surveillance to surgery or gradual decline with radiation treatment, he acknowledged.

Men with favorable prognoses at baseline who underwent surgery saw significantly worse urinary incontinence at 10 years compared with those started on radiotherapy or active surveillance. And EBRT was associated with fewer incontinence issues compared with active surveillance.

Among the group of men with an unfavorable prognosis at baseline, 64% of whom underwent radical prostatectomy and 36% EBRT with ADT, surgery was associated with worse urinary incontinence but not worse sexual function throughout 10 years of follow-up, compared to radiotherapy with androgen deprivation therapy.

Radiation-treated patients with unfavorable prognoses, meanwhile, saw significantly worse bowel function and hormone function at 10 years compared with patients who had undergone surgery.

Dr Al Hussein Al Awamlh said that a strength of this study was that "we had enough patients to stratify functional outcomes based on disease prognosis." Another key finding was that some of the outcomes changed over time. "For example, among the patients with unfavorable prognoses, at 10-year follow-up there was slightly worse bowel and hormone function seen associated with radiation with ADT compared with surgery," he said — something not seen at earlier follow-up points.

The findings may help offer a more nuanced way to counsel patients, Dr Al Hussein Al Awamlh noted. For example, the side effects associated with sexual function "are not as relevant for those with unfavorable disease," he said.

While current prostate cancer guidelines do address quality of life in shared decision-making, he said, "hopefully this data may provide more insight on that." For patients with favorable prognosis, the findings reinforce that "active surveillance is a great option because it avoids the effects associated with those other treatments."

Ultimately, Dr Al Hussein Al Awamlh said, "this is a patient preference issue. It's important for patients to understand how different functions are affected and to decide what is better for them — what they can live with and what they cannot, provided all the options are oncologically safe."

The study authors disclosed as limitations of their study its observational design, the potential for response bias among study participants, and small numbers for some of the measured outcomes.

In an interview, urologist Mark S. Litwin, MD, of the University of California, Los Angeles, characterized the study as "a well-conducted, very-long-term longitudinal cohort that tracked men long past the initial diagnosis and treatment. That empowered the Vanderbilt team to find differences in quality of life many years later and compare them to other older men who had not received treatment."

The new findings, Dr Litwin said, "are critical in showing that most men with prostate cancer do not die from it; hence, the quality-of-life effects end up being the key issues for decision-making."

Dr Al Hussein Al Awamlh and colleagues' study was funded by grants from the National Institutes of Health, the Agency for Healthcare Research and Quality, and the Patient-Centered Outcomes Research Institute. Several coauthors disclosed funding from pharmaceutical and/or device manufacturers. Dr Litwin disclosed no conflicts of interest related to his comment. 

This article originally appeared on MDedge.com, part of the Medscape Professional Network.