Probability of prostate cancer on biopy according to serum PSA level in Korean men : Is there any difference from American Men?

초록

Introduction: The incidence of prostate cancer (PCa) is increasing in Korea. However comparing with western people the incidence is relatively low. The detection rate of PCa according to serum PSA level is supposed to be lower in Korean, but is not yet known. We reviewed prostate biopsies (PBx) retrospectively and evaluated the probability of PCa on biopsy according to serum PSA level in Korean men. Material and methods: We reviewed 2,422 Korean men who had PBx retrospectively. In case that PSA level is higher than 4ng/ml, PBx were performed. And also biopsy was performed in patients with abnormal DRE or abnormal prostate image on TRUS regardless of serum PSA level. Result: Of the 2422 men, 39.7% had a positive biopsy. In PSA level less than 4 ng/ml, 12.4% of men had PCa. In PSA level between 4 and 10 ng/ml, the detection rate of PCa was 15.9% (141/889). This rate is similar with that of Japanese (15.8 %) and quite different from that of Americans (25%). In PSA level above 10, 59.4% of men had a positive biopsy. There was no difference in probability of PCa on biopsy according to prostate volume. For values of PSA less than 20 ng/ml, 20.1% (308/1533) had a positive biopsy. Among 308 cancer patients whose PSA level under 20 ng/ml, 9.7% of patients were clinical stage D diseases. For PSA of > 4 ng/ml, positive and negative predictive values were 42.0% and 87.6%, respectively. For PSA of > 10 ng/ml, positive and negative predictive values were 59.1% and 84.6%, respectively. Conclusion: The probability of PCa according to PSA level in oriental people is different from that of Caucasians especially in gray zone. As the incidence of stage D PCa in Korean with PSA level under 20ng/ml is relatively high compared with that of American great care should be taken in Korean. The positive and negative predictive values of Korean were quite similar with those of Japanese, but a little different from of Americans.