New Thresholds for Prostate-specific Antigen Velocity for Prostate Cancer Screening in Korean Patients Younger than 60 Years Old / 대한비뇨기과학회지

ABSTRACT

PURPOSE: We identified new thresholds for prostate-specific antigen velocity(PSAV) for screening of prostate cancer in Korean patients younger than 60 years old based on PSA serial data obtained from our hospital's health promotion center. MATERIALS AND METHODS: The study population was retrieved from 10,011 patients, 40 to 79 years old, with 2 or more PSA values within five years who visited our hospital's health promotion center between January 2002 and December 2006, including 100 patients with prostate cancer. These subjects were divided into 2 age groups, 40-59 years old and 60-79 years old, and their PSAV were calculated as the rate of PSA change using the first and last values only. A receiver operating characteristic(ROC) curve was used to analyze the performance of PSAV in the screening of prostate cancer, and we developed new PSAV thresholds by comparing sensitivity and specificity at different PSAV levels. RESULTS Overall prostate cancer prevalence was 0.6%(45) in younger(40-59 years old) patients and 2.1%(55) in older(60 to 79 years old) patients. The median PSAV in the normal control group and the cancer group were 0.047ng/ml/year vs 0.877ng/ml/year in younger patients(p<0.0001) and 0.067ng/ml/year vs 0.642ng/ml/year in older patients(p<0.0001). For younger patients, the sensitivity and specificity were 55.6% and 99.2% at PSAV 0.75ng/ml/year, but decreasing the PSAV cut-points to 0.35ng/ ml/year improved sensitivity to 78% for cancer detection in this age group. CONCLUSIONS: The previous PSAV threshold for prostate biopsy, 0.75 ng/ml/year or greater, probably underestimate cancer risk in younger Korean men. Decreasing PSAV thresholds to 0.35ng/ml/year would improve screening sensitivity.