Use of active surveillance (AS) for intermediate-risk prostate cancer (PCa) nearly doubled from 2010 to 2015 in the United States, according to new national data. AS adoption increased the most among older men and those with favorable intermediate-risk disease.
Vinayak Muralidhar, MD, of Dana-Farber Cancer Institute, Brigham and Women’s Hospital, Boston, and his colleagues used the Surveillance, Epidemiology, and End Results Active Surveillance/Watchful Waiting database to identify 52,940 men with intermediate-risk PCa (cT2b-c, Gleason score 7, or PSA 10-20 ng/mL). Of these, 22,224 (42.0%) were initially managed with radiation therapy (RT), 27,493 (51.9%) with radical prostatectomy (RP), and 3223 (6.1%) with AS.
Use of AS increased from 3.7% in 2010 to 7.3% in 2015, the team reported in Cancer. AS uptake significantly increased from 7.2% to 14.9% among men with favorable-risk disease and increased to a lesser extent among men with unfavorable risk disease: 2.2% to 3.8%. The likelihood of AS was 4-fold higher for favorable than unfavorable risk patients.
The mean age of men adopting AS significantly decreased from 69.9 to 67.9, suggesting increasing physician comfort with the approach. The likelihood of AS was 1.5- and 3-fold higher among men aged 70 years and older than those aged 60 to 69 years and younger than 60 years, respectively. Men residing in the West, Northwest, or Midwest were nearly twice as likely to select AS compared with men living in the Northeast and South. Black race and higher socioeconomic status, but not insurance status, also were associated with higher AS uptake.
Importantly, the investigators examined early survival outcomes by comparing the cohort with intermediate-risk disease to a cohort of 45,915 patients with low-risk disease. Cancer-specific mortality at 5 years was no worse among men with low-risk disease opting for AS rather than definitive treatment. Significantly worse cancer-specific survival was observed for men with unfavorable intermediate-risk PCa who underwent AS compared with those who received RT or RP: 1.3% vs 0.5%. Among men with unfavorable intermediate-risk PCa, AS was associated with a significant 2.5-fold increased risk of dying from their cancer than men who received RT or RP, in adjusted analyses. A nonsignificant difference was observed for men with favorable risk disease who selected AS instead of treatment: 1.0% vs 0.2%.
“Therefore, the current study data affirm NCCN [National Comprehensive Cancer Network] guidelines indicating that caution should be applied when considering AS for men with favorable intermediate-risk disease as we await longer follow-up data regarding population-wide outcomes with AS,” Dr Muralidhar and the team stated. They also acknowledged an increase in AS among patients with unfavorable intermediate-risk disease, which is outside of NCCN standard of care: “This may represent ‘indication creep’ from trends in patients with lower risk disease, or provider unawareness of risk features defining favorable versus unfavorable intermediate-risk disease,” they suggested.
Butler SS, Mahal BA, Lamba N, et al. Use and early mortality outcomes of active surveillance in patients with intermediate-risk prostate cancer. Cancer. 2019;0:1-8.