As the rates of high-risk prostate cancer in the U.S. increased in recent years, use of prostatectomy nearly doubled while radiotherapy declined, new research from the National Cancer Database (NCDB) found.
From 2004 to 2016, the proportion of prostate cancer cases classified as high risk increased from 11.8% to 20.4%, and use of prostatectomy in this population rose from 22.8% to 40.5% during this time (P<0.001 for both), according to Himanshu Nagar, MD, a radiation oncologist at Weill Cornell Medicine in New York City, and colleagues.
This increase in surgery was met with declines in radiotherapy use for high-risk patients, which fell from 59.7% to 43.3% over this stretch of time (P<0.001), the group reported in JAMA Network Open.
These shifts in treatment patterns have taken place without guideline evidence suggesting superiority of prostatectomy, Nagar’s group noted.
“The increasing use of robotic approaches suggests urologists and patients may regard prostatectomies safer than previous techniques,” the authors wrote. “Conversely, a decrease in radiotherapy may reflect reluctance toward recommended androgen deprivation therapy with radiotherapy.”
From 2004 to 2013, the likelihood that a patient would receive prostatectomy increased, and then held steady through 2016 (OR 2.34, 95% CI 2.12-2.48, P<0.001). This increase was observed regardless of race, though Black men were still less likely to undergo surgery across the study period (OR 0.57, 95% CI 0.55-0.59, P<0.001).
Several factors increased the odds of prostatectomy, including higher income and education, treatment at an academic center, and having private insurance. Conversely, higher Gleason score, disease stage, prostate-specific antigen (PSA) levels, and age, as well as living in a rural area all reduced the odds of undergoing surgery.
Radiotherapy and prostatectomy are both standard options for men with high-risk prostate cancer — defined as clinical stage T3-T4, high Gleason scores (8-10), or PSA levels over 20 ng/mL. Comparisons of the two approaches have shown conflicting results in single-center studies, though some population-based analyses have favored surgery.
A study in Gleason 9-10 tumors showed improved prostate cancer-specific mortality with external-beam radiation therapy (EBRT) plus a brachytherapy boost versus surgery or EBRT alone, but no difference between surgery and EBRT alone. In the current analysis, few patients received a brachytherapy boost.
“Randomized data comparing modalities do not and likely will not exist in the foreseeable future to determine optimal treatment,” the authors wrote. “The ProtecT trial compared prostatectomy vs radiotherapy and showed no difference in prostate-cancer specific mortality, but did not include a significant number of patients with high-risk prostate cancer.”
Similarly, the ongoing PACE (Prostate Advances in Comparative Evidence) trial is restricted to low- or intermediate-risk prostate cancer.
For their study, Nagar’s group examined the treatment for 214,972 men in the NCDB diagnosed with high-risk prostate cancer from 2004 to 2016. More than three-fourths (78%) of the cohort were diagnosed after age 60, with 79.2% white and 16.1% Black. Most men were treated with either prostatectomy (n=104,635) or radiotherapy (n=75,847), with 12.6% receiving EBRT. Gleason score of 4+4 was most common (35%), followed by 4+5 (21.1%), 3+4 (12.2%), and ≤6 (11.2%).
Limitations of the study included its restrospective design.
Study authors reported having no conflicts of interest.