Active surveillance for low-risk prostate cancer (PCa) in African-American men is a safe and reasonable option, despite evidence suggesting they are more likely than Caucasian men to have worse pathologic and oncologic outcomes, researchers concluded in a recent literature review.
The authors of the review, Jonathan L. Silberstein, MD, and colleagues at Tulane University School of Medicine in New Orleans, acknowledged that the available literature remains unclear regarding the risks and outcomes for African-American (AA) patients selecting active surveillance (AS), but the researchers said they are confident about using AS in AA patients “because AS patients are a heavily screened population.”
Dr. Silberstein’s team pointed out that some issues central to any consideration of AS remain unresolved, regardless of patient race, such as the criteria used to select appropriate AS candidates, how intensively patients on AS should be monitored, and defining disease progression while on AS.
The authors stated that the AS protocol at their institution involves multiparametric magnetic resonance imaging within 6 months of initial diagnosis followed by directed biopsies. Repeat physical examinations and PSA measurements are obtained every 6 months, with repeat imaging and biopsy at 24 months.
“Our use of aggressive imaging, biopsy, and follow-up regimens is likely to mitigate any increased risk, which remains unclear in AA,” they concluded.
Various studies have shown that AA patients with low-risk PCa are more likely than Caucasians to experience disease progression, such as upgrading on repeat biopsy, and positive surgical margins found at radical prostatectomy.
Earlier this year, a team led by Ranko Miocinovic, MD, of the Detroit Medical Center, reported in Urology (2014;83:364-368) that AA men on AS for low-risk PCa have a nearly 4-fold increased risk of disease progression compared with non-AA men, and concluded that AA men may need closer follow-up than non-AA men.
The study, which included 67 AA men and 72 non-AA men who had a median follow-up of 34 months and 46 months, respectively, also showed that a significantly smaller proportion of AA men than non-AA men remained on AS (66% vs. 82%) at follow-up.
In a study of 4,231 men with low-risk PCa who were eligible for AS but underwent RP within 1 year, a team led by Matthew R. Cooperberg, MD, of the University of California San Francisco, found that AA patients were 64% more likely than Caucasians to have positive surgical margins, according to a report published online ahead of print in European Urology.
In an editorial accompanying the report by Dr. Silberstein’s group, Debasish Sundi, MD, and Edward M. Schaeffer, MD, PhD, of the James Buchanan Brady Urological Institute at Johns Hopkins University in Baltimore, said it is unknown whether very low-risk AA men considered or enrolled in AS and who have their cancer upgraded at surgery or have treatment triggered by biopsy upgrading experience higher risks of metastases and PCSM.
They pointed out, however, that the National Comprehensive Cancer network guidelines suggest that patients with adverse pathologic features or biochemical recurrence should undergo secondary radiotherapy and, in certain situations, secondary androgen deprivation therapy (ADT). In addition, guidelines suggest that patients with high-grade cancers receiving radioterhapy should also receive combined treatment with ADT.
“Therefore, PCa racial disparities among AS candidates not only affect outcomes on surveillance but also the oncologic outcomes and cancer-directed therapies on treatment,” Drs. Sundi and Schaeffer wrote. “Most importantly, identifying the biologic basis of these disparities may shed light on the crucial distinction between indolent and aggressive PCa.”