Prostate cancer active surveillance criteria may need to be stratified by race

New Brunswick, NJ-African-American men eligible for active surveillance have a higher risk of advanced cancer on final surgical pathology compared to Caucasian men, suggesting the need for more stringent criteria for active surveillance for African-American men, according to a recently published study.

“The rate of non-organ-confined disease in African-American men with low-risk prostate cancer is twice that of white men,” said senior author Isaac Yi Kim, MD, PhD, chief and associate professor of urologic oncology and executive director of the Dean and Betty Gallo Prostate Cancer Center at the Cancer Institute of New Jersey, Robert Wood Johnson Medical School, New Brunswick, NJ.

In the study, which was published in Urology (2013; 81:831-6), Dr. Kim and co-authors retrospectively analyzed data from a prospectively maintained database of men who underwent radical prostatectomy between 1997 and 2011 at the Cancer Institute of New Jersey and Johns Hopkins University, Baltimore. All participants met eligibility criteria for active surveillance based on two different guidelines: the University of California, San Francisco (UCSF) criteria that bases active surveillance on PSA score of ≤10.0 ng/mL, biopsy Gleason sum ≤6 with no pattern 4 or 5, cancer involvement of ≤33% of biopsy cores, and clinical stage T1/T2a tumor; and the National Comprehensive Cancer Network (NCCN) criteria that bases active surveillance on life expectancy <10 years with a PSA of <10.0 ng/mL, clinical stage ≤T2a, Gleason sum ≤6; or life expectancy up to 20 years with PSA <10.0 ng/mL, clinical stage ≤T2a, Gleason score ≤6, fewer than three biopsy cores, and ≤50% positive core.

A total of 1,536 African-American men were identified, 196 of whom were eligible for active surveillance based on UCSF criteria and 124 on NCCN criteria. To compare this cohort to Caucasian men, the study included 608 Caucasian men who underwent radical prostatectomy during the same time period and were eligible for active surveillance based on the UCSF criteria (191 men) and NCCN criteria (143 men).

The authors found that African-American men had a significantly higher percentage of maximum biopsy core than Caucasian men under both active surveillance criteria (15.3%-20.4% vs. 11.5%-15.0%, respectively; p=.05) as well as multiple positive biopsy cores under the NCCN criteria (45.2% vs. 33.1%, p=.046).

More advanced disease in African-Americans

The authors also found a higher proportion of African-American men had advanced disease compared to Caucasian men when comparing the rate of pathologic upstaging and Gleason upgrading. Under the NCCN criteria, the frequency of advanced disease in African-American men was significantly higher than in Caucasian men (46.0% vs. 39.2%) as shown by the significantly higher incidence of upstaging (≥pT3) in African-American men compared to Caucasian men (19.4% vs 10.1%, p=.037). Under the UCSF criteria, a trend for increased incidence of non-organ-confined disease was found in African-American men compared to Caucasian men as shown by the higher incidence of upstaging (15.8% vs. 9.4%, p=.067). Under both criteria, no difference was found between African-Americans and Caucasians in the rate of upgrading.

“Because the rate of upgrading was similar between African-American and Caucasian patients, the increased frequency of pathologic T3 prostate cancer in African-American men with low-risk prostate cancer suggests that even ‘small’ prostate cancers are inherently more aggressive in African-American men,” said Dr. Kim in reply to an editorial that accompanied the article.

Based on these results, Dr. Kim and his colleagues suggest more stringent criteria for active surveillance among African-American men and the need for further study to determine such criteria.

“Until further studies are completed, urologists should be very conservative in recommending active surveillance to African-American men,” Dr. Kim said.UT