Background: Prostate cancer is a major problem and the prostatic specific antigen (PSA) blood test is the most effective test for early detection. There is, however, a paucity of confirmatory prevalence data for the Thai population.
Objective: To determine the prevalence of prostate cancer in the northeastern region of Thailand.
Material and Method: This was a cross-sectional study at the Health Check-up Clinic of Srinagarind Hospital between July 2008-2009. Recruits included 129 patients > 45 years of age. Prostatic specific antigen (PSA) was measured and patients with a high PSA level were counseled to undergo a transrectal ultrasound (TRUS)-guided biopsy. The cancer detection rate was calculated and the specificity of the diagnostic test determined using the ROC curve. The Spearman correlation between the PSA level and the Gleason score was established.
Results: The respective mean age and PSA level was 61 and 2.3 ng/ml. Thirteen patients had a PSA level > 4 ng/ml; all of whom underwent TRUS-guided biopsy; eight were positive for prostate adenocarcinoma. The prevalence of prostate cancer was thus 6.2% (8/129 patients). The specificity of the cut-off PSA level at 4 ng/ml as per the ROC curve was 40%. There was no correlation between the PSA level and the Gleason score.
Conclusion: The prevalence of prostate cancer was 6.2%. According to the ROC curve, a cut-off PSA level of 4 ng/ml would be an appropriate for prostate cancer screening among Thai males.

Keywords: Screening, Prostatic specific antigen, Aging