Black men with low-risk prostate cancer undergoing active surveillance had a significantly increased incidence of disease progression and a higher likelihood of needing definitive treatment compared with white men, but did not have an increased incidence of metastasis or prostate-cancer specific mortality, according to a study of men in the Veterans Health Administration (VHA) system.
The retrospective study of 8,726 men in the VHA, including 2,280 Black men, followed for a median 7.6 years showed similar rates of prostate cancer-specific mortality (1.1% vs 1.0%) for Black vs white men despite a more than 10% difference in 10-year cumulative incidence of disease progression (59.9% vs 48.3%; P<0.001) and receipt of definitive treatment (54.8% vs 41.4%; P<0.001), reported Brent S. Rose, MD, of University of California San Diego Health, Moores Cancer Cancer, and colleagues.
In their study, published online in JAMA, active surveillance was defined as no definitive treatment within the first year of diagnosis and undergoing at least one additional surveillance biopsy. The team noted that previous research looking at active surveillance included very few Black men, meaning that the results may not have been generalizable to this patient population.
In the new study, multivariable analysis showed that Black men with prostate cancer were about 30% more likely to have disease progression (subdistribution hazard ratio [SHR] 1.3, 95% CI 1.2-1.4, P<0.001) and receive definitive treatment (SHR 1.3, 95% CI 1.2-1.4, P<0.001) compared with white men.
Despite this increased risk, however, the rates of metastatic disease were similar between the two groups: cumulative incidence at 10 years of 1.5% for Black men and 1.4% for white men.
Additionally, prostate-cancer specific and all-cause mortality rates were similar between the two patient populations, with Black men having no increased risk on multivariable competing risk regression analyses, the researchers reported.
They cautioned, though, that longer-term follow-up is needed to better assess the mortality risk.
“Hopefully, these results encourage African American men with low-risk prostate cancer to consider active surveillance,” Rose told MedPage Today. “Additionally, these findings may support higher rates of PSA screening and early detection if men know that they may not need treatment if they find a low-risk cancer. This will help us to identify the aggressive cancers that do need to be treated in order to reduce the disparity in prostate cancer outcomes for African American men.”
Writing in an accompanying editorial, Xinglei Shen, MD, MS, of the University of Kansas Medical Center in Kansas City, and colleagues acknowledged the dearth of data about whether active surveillance — the use of which is increasing, they note — is as safe for Black prostate cancer patients as it is for white men with the disease.
“This is because prior studies have shown that among Black patients, compared with White patients, the onset of prostate cancer is earlier and tumor volumes are greater even among men with low-risk disease,” the editorialists wrote. “Further, existing data show that Black patients with low-risk prostate cancer who underwent radical prostatectomy were