In prostate cancer, personalized medicine may be life-saving. “As we learn more about prostate cancer, we are beginning to see that not all ethnic groups are the same,”says Jonathan Epstein, M.D., the Rose-Lee and Keith Reinhard Professor in Urologic Pathology.

For example: In important new studies, Epstein and colleagues have discovered that prostate cancer in African American men makes less PSA than it does in Caucasian men. This work suggests that in African American men, low-grade prostate cancer (a Gleason score of 3+3=6, or Grade Group 1) may not be as slow-growing as it is in Caucasian men. “Active surveillance is often recommended for men with low-grade prostate cancer,” says Epstein. “However, the criteria for choosing who the best candidates for active surveillance are have been based primarily on studies of Caucasian men.”But in several studies, Epstein and colleagues have been working to add more specific data to the knowledge base. They found that the current criteria for active surveillance “do not work as well in African American men compared to Caucasian men.”

Then they demonstrated “that among men with the same volume of low-grade cancer, despite larger overall prostates, African American men had the same PSA.” They explained this finding by showing that cancer in African American men makes less PSA than it does in Caucasian men. “PSA Density (the PSA score divided by the volume of the prostate, as determined by ultrasound) was about 20 percent lower in African American compared to Caucasian men — even though tumor volume was the same,” Epstein continues. “This finding could be a factor in why current active surveillance criteria in African American men are not as accurate as those for Caucasians.” Epstein suspects that to account for this disparity, the threshold for PSA density will need to be made lower for African American men who want to take part in active surveillance, “with the hope that this will allow us to predict more accurately which African American men will be good candidates for active surveillance.”

Their most recent work was published in the Journal of Urology.