Probability of prostate cancer on biopy according to serum PSA level in Korean men and availability of PSA related parameters in grey zone PSA

초록

Objectives:Prostate cancer(PCa) is rapidly increasing in Korea. We studied the detection rate of PCa according to the PSA range, and evaluated whether free-to-total PSA ratio and PSAD could attribute to sensitivity or specificity in patients wth serum PSA between 4 and 10ng/ml. Materials:We analysed the data of 2,300 patients who underwent transrectal prostate biopsy due to serum PSA elevation or abnormal DRE at 12 hospitals in Korea from 1995 to 2003. Among 2300 patients, 13 were excluded due to insufficient pathologic specimens. Serum PSA, free PSA, prostate volume were checked before biopsy. We evaluated the cancer detection rate according to the PSA range and investigated the sensitivity and specificity of free PSA cutoff of <15% as a criterion for prostate biopsy and PSA density cutoff of > 0.15. Results:Serum PSA was between 0 and 4ng/ml in 191 patients, between 4 and 10 in 843, 10 and 20 in 512, 20 and 100 in 476, and over 100ng/ml in 276. The cancer detection rates were 12.4%, 16.1%, 34.8%, 63.1%, and 94.4%, respectively. Free to total PSA ratio and PSAD were available in 313 patients among 843 whose PSA were between 4 and 10ng/ml. In patients with PSA between 4 and 10, there was no significant difference in serum PSA and free PSA level between biopsy positive and negative groups. PSA density was 0.216±0.001 in biopsy positive group and 0.172±0.004 in the negative(p<0.001). In patients with PSA between 4 and 10, using free PSA cutoff of <15% as a criterion for prostate biopsy, sensitivity was 70.51% and specificity 40.85%. Using PSA density cutoff of > 0.15, sensitivity was 75.64% and specificity 40.43%. Conclusions:The PCa detection rate in Koreans according the PSA range was similar to those of other articles. However, the sensitivity and specifity of free to total PSA ratio and PSA density in those with PSA between 4 and 10ng/ml were low in comparison with other articles. Thus investigation to adjust these parameters for Koreans is warranted.