High prevalence of screening-detected prostate cancer among Afro-Caribbeans: the Tobago Prostate Cancer Survey

Abstract

Risk for prostate cancer is high among African Americans. We hypothesized that risk for prostate cancer is also high in other populations of African descent. Our objective was to determine the screening-detected prevalence of prostate cancer in the predominantly Afro-Caribbean population on the island of Tobago. Male residents, ages 40-79 years, were invited to participate in a population-based screening for prostate cancer using serum prostate-specific antigen (PSA) and digital rectal exam (DRE). Men with elevated PSA (>or=4 ng/ml) or abnormal DRE were offered an ultrasound-guided sextant biopsy of the prostate gland. Men (2484), ages 40-79 years, underwent prostate cancer screening between September 1997 and June 2001. Mean age was 55.9, SD was 10.6 years, and median was 54 years. Mean serum PSA was 14.8 ng/ml, SD was 376 [excluding 4 values >or= 2 SD above the mean (1,112, 1,317, 1,818, and 18,330 ng/ml) mean PSA was 5.5 ng/ml and SD was 29.6], and median PSA was 1.2 ng/ml. Elevated PSA and/or abnormal DRE were observed in 31% (759 of 2484) overall, and in age groups 40-49 (87 of 843, 10%), 50-59 (201 of 729, 28%), 60-69 (262 of 584, 45%), and 70-79 (209 of 328, 64%). Of 681 men biopsied, 259 (38%, or 10% of the 2484 screened) were diagnosed with prostate cancer. Age-specific rates of screening detected prostate cancer were: 1%, ages 40-79 years; 7%, ages 50-59 years; 18%, ages 60-69 years; and 28%, ages 70-79 years. These screening results indicate a very high screening-detected prevalence of prostate cancer in this population of West African descent. These data support the hypothesis that populations of African descent share genetic and/or lifestyle factors that contribute to their elevated risk for prostate cancer.