Optimal baseline prostate-specific antigen level to distinguish risk of prostate cancer in healthy men between 40 and 69 years of age

Abstract

The present study evaluated optimal baseline prostate-specific antigen (PSA) level at different ages in order to determine the risk of developing prostate cancer (CaP). We analyzed 6,651 Korean men, aged 40-69 yr. The serum PSA levels for these men were measured at one institute from 2000 to 2004 and were determined to be between 0-4 ng/mL. Patients were divided into 4 groups of 25th-percentile intervals, based on initial PSA level. Of these, the group with an increased risk was selected, and the optimal value was determined by the maximal area under a receiver-operating characteristic curve within the selected group. The risk of CaP diagnosis was evaluated by Cox regression. The mean follow-up period was 8.3 yr. CaP was detected in 27 of the 6,651 subjects. CaP detection rate was increased according to age. The optimal PSA value to distinguish the risk of CaP was 2.0 ng/mL for 50- to 69-yr-olds. Patients with a baseline PSA level greater than the optimal value had a 27.78 fold increase in the prostate cancer risk. Baseline PSA values are useful for determining the risk of developing CaP in Korean men for 50- and 69-yr-old. We suggest that PSA testing intervals be modified based on their baseline PSA levels.

Keywords: Asian Continental Ancestry Group; Prostate Neoplasm; Prostate-Specific Antigen; Screening.

Fig. 1

Cumulative prostate cancer-free survival according to the age and baseline PSA percentile. Survival curves for men aged (A) 40 to 69 yr, (B) 40 to 49 yr, (C) 50 to 59 yr and (D) 60 to 69 yr. Markers represent prostate cancer and censored cases. With time, prostate cancer incidence increased significantly in men with a baseline PSA more than the 75th percentile (reverse triangle), except for men in their 40s (log-rank test for trend).

Fig. 2

Trend of the area under the curve according to a baseline PSA cut-off value greater than the median PSA level in men 50 to 69 yr old. AUC, area under the curve; PSA, prostate-specific antigen.