Active surveillance not linked to higher mortality for Black men with prostate cancer
Black men with low-risk prostate cancer had a significantly higher 10-year cumulative incidence of disease progression and definitive treatment than white men, according to results of a retrospective cohort study published in JAMA.
However, incidence of metastasis, prostate cancer-specific mortality and all-cause mortality did not differ significantly between Black men and white men, researchers noted.
“It was once thought that active surveillance was not safe for Black men because of a perception that prostate cancer was inherently more aggressive in this population, which led to unnecessary treatments and side effects, such as urinary incontinence, erectile dysfunction and bowel problems for Black men,” Brent S. Rose, MD, assistant professor of radiation oncology at University of California, San Diego, told Healio. “However, our study showed that Black men who underwent active surveillance instead of immediate treatment were not more likely to have their cancer spread or to die of the disease.”
Rose and colleagues compared clinical outcomes of 2,280 Black men (median age, 63.2 years) and 6,446 white men (median age, 65.5 years) with low-risk prostate cancer (Gleason score 6; clinical tumor stage 2A; and PSA level 10 ng/dL) who received active surveillance in the U.S. Veterans Health Administration health care system between 2001 and 2015. Final follow-up was March 31, 2020.
Researchers defined active surveillance as no definitive treatment within the first year of diagnosis and at least one additional surveillance biopsy.
Primary outcomes included progression to at least intermediate-risk disease, definitive treatment, metastasis, prostate cancer-specific mortality and all-cause mortality.
Median follow-up was 7.6 years (interquartile range, 5.7-9.9).
Ten-year follow-up data were available for 499 Black men (21.9%) and 1,582 white men (24.5%).
Results showed Black men had a higher 10-year cumulative incidence of disease progression than white men (59.9% vs. 48.3%; difference, 11.6%; 95% CI, 9.2-13.9), as well as a higher cumulative incidence of definitive treatment at 10 years (54.8% vs. 41.4%; difference, 13.4%; 95% CI, 11-15.7).
Ten-year cumulative incidence of metastasis (1.5% vs. 1.4%; difference, 0.1%; 95% CI, –0.4 to 0.6), prostate cancer-specific mortality (1.1% vs. 1%; difference, 0.1%; 95% CI, –0.4 to 0.6) and all-cause mortality (22.4% vs. 23.5%; difference, 1.1%; 95% CI, –0.9 to 3.1) did not differ significantly between Black men and white men.
Results of multivariable competing risks regression showed Black men were significantly more likely to have disease progression (subdistribution HR [sHR] = 1.3; 95% CI, 1.2-1.4), a PSA level of 10 ng/dL or higher (sHR = 1.3; 95% CI, 1.1-1.5) and a Gleason score higher than 6 (sHR = 1.4; 95% CI, 1.2-1.5). In addition, Black men had a significantly higher likelihood of receiving definitive treatment (sHR = 1.3; 95% CI, 1.2-1.4) but were not more likely to experience metastasis (sHR = 1.2; 95% CI, 0.8-1.9), prostate-cancer specific mortality (sHR = 1.2; 95% CI, 0.7-2.1) or all-cause mortality (sHR = 1; 95% CI, 0.9-1.1).
“It is important to note that active surveillance needs to be done carefully, since Black men were more likely to need treatment at some point in their life,” Rose said. “If patients are not followed carefully, it is possible that they could have disease progression and miss the opportunity to have their cancer cured. Future research should try to understand why patients on active surveillance might progress to require treatment and why this seems more common in Black men.”
Although the findings suggest that active surveillance can be safe and effective for Black men, a note of caution should be raised about generalizing results from the equal-access U.S. Veterans Health Administration health care system to more common care contexts, according to an accompanying editorial by Xinglei Shen, MD, MS, radiation oncologist at University of Kansas Medical Center, and colleagues.
“Because Black patients have more biologically aggressive prostate cancer and higher progression rates during active surveillance compared with white men, there is a greater need for Black men in the general population to have access to high-quality and timely care to avoid delays in diagnosing cancer progression and receiving definitive treatment,” they wrote. “However, existing literature has repeatedly demonstrated widespread inequities whereby Black patients with prostate cancer compared with white patients are less likely to receive radical prostatectomy and radiotherapy and are more likely to experience treatment delays. ... Further reassurance would be gained from research showing similar outcomes in broader general population settings outside of the U.S. Veterans Health Administration health care system context.”
- Deka R, et al. JAMA. 2020;doi:10.1001/jama.2020.17020.
- Shen X, et al. JAMA. 2020;doi:10.1001/jama.2020.16315.
For more information:
Brent S. Rose, MD, can be reached at University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093; email: firstname.lastname@example.org.