PSA as prostate cancer predictor shows racial tie

November 1, 2005

Vancouver, British Columbia--African-American men may have a greater risk of developing prostate cancer than Caucasian men, but the specific reasons for this difference have not been fully established.

"Recently, people have suggested that the increased risk [for African-American men] is disappearing because of increased awareness and screening for prostate cancer. But we tried to show that they are still at increased risk despite having better access to health care," said Kalyan C. Latchamsetty, MD, a fellow working with Christopher R. Porter, MD, at the Virginia Mason Medical Center in Seattle.

In a study of 914 men, Dr. Latchamsetty and Dr. Porter found that independent predictors of prostate cancer for African-American men include PSA scores, no previous biopsy, digital rectal examination, a low AUA Symptom Score, and race. By contrast, only age and abnormal transrectal ultrasound were independent predictors in Caucasian men. Dr. Latchamsetty presented the findings in a poster at the AUA Western Section annual meeting here.

"DRE has come under a lot of scrutiny as a predictor of prostate cancer. From our database, it still is an independent predictor," he added.

The study results are useful for counseling African-American men with an elevated PSA level when they see a urologist, Dr. Latchamsetty said. African-American patients should undergo screening annually after the age of 40 years, whereas screening is recommended for Caucasian men after age 50, according to AUA guidelines.

The analysis was part of a prospective study conducted by Dr. Porter between January 2000 and July 2004. Participants-71.5% Caucasian and 28.5% African-American-with a mean age of 63 years were prospectively examined by a urologist prior to undergoing prostate needle biopsy.

Prior to biopsy, the mean PSA for the entire cohort was 11.2 ng/mL; the median was 5.8 ng/mL. Abnormal TRUS was evident in 37% of the cohort, and abnormal DRE in 52% of the men. The mean AUA Symptom Score was 9.6. The overall positive biopsy rate was 37%; in African-American men, the rate was 43% compared with 35% in Caucasian men.

The results of AUA Symptom Score analysis showed that 47% of the men scored <7 (low), 39% had scores of 8 to 19 (moderate), and 14% had scores between 20 and 35 (severe). Subset multivariate analysis was carried out on 366 men with low AUA Symptom Score, which indicated that race was an independent predictor of prostate cancer (p=.002). In 99 men with a high AUA Symptom Score, race also was found to be a significant independent predictor of prostate cancer (p<.05).