Comparison of the Predictive Accuracy of Serum Prostate Specific Antigen Levels and Prostate Specific Antigen Density in the Detection of Prostate Cancer in Hispanic-American and White Men

Abstract

The Hispanic-American population is the fastest growing in the United States. Although many studies have looked at the performance of prostate specific antigen (PSA) in the detection of prostate cancer in white and black men, few have looked at it in relation to Hispanic men. The objective of this study was to compare the performance of PSA and PSA density (PSAD) in the detection of prostate cancer in Hispanic and white men. A total of 404 consecutive Hispanic and 341 consecutive white men with elevated serum PSA and/or abnormal digital rectal examination underwent transrectal ultrasound with lesion directed and systematic peripheral zone biopsies from 1996 to 2001 at a single institution by 2 investigators (ETG, MCB). Before biopsy all patients underwent volume measurements of the entire prostate. Of these patients 242 Hispanic and 255 white men had a total PSA between 2.5 and 10 ng/ml. Serum PSA and calculated PSAD were compared between the positive and negative biopsy groups, and between Hispanic and white men. Of the 242 Hispanic and 255 white men 85 (35.1%) and 63 (24.7%) had cancer, respectively (p = 0.0147). There was no significant difference in age among the groups. There was no significant difference in median PSA between Hispanic and white men, or white men with malignant versus benign disease. There was a significant difference in median PSA in Hispanic men with malignant versus benign disease (6.3 vs 5.2 ng/ml, p = 0.0072). For PSAD there was a significant difference between Hispanic men with malignant versus benign disease (0.17 vs 0.12, p <0.0001) and white men with malignant versus benign disease (0.13 vs 0.11, p = 0.0019). Overall there was a difference in PSAD between positive and negative biopsy groups, and there was a significant difference in PSAD between Hispanic and white men (0.13 vs 0.11, p <0.0001). This study shows for the first time that at similar levels of total PSA, PSAD is higher in Hispanic than in white men. Furthermore, these data show that while PSA was able to discriminate between malignant versus benign disease in Hispanic men, it was not able to do so in white men. Given the large number of patients in this series perhaps different PSAD cutoffs need to be defined for Hispanic men. Further study in this area is warranted.