Cancer - Prostate(구연) (NP-055) 첫번째 전립선 조직검사를 받는 환자와 이전 조직검사에서 양성(benign)으로 나온 환자에서 PI-RADS 점수와 PSA density 를 이용한 전립선 암 발견 성균관대학교 의과대학 비뇨기과학교실 유현수, 강민용, 성현환, 정병창, 서성일, 전성수, 이현무, 전황균 Purpose: It is important to avoid undergoing unnecessary prostatic biopsies at the same time we should not miss prostate cancer. Therefore, we determined the predictive values of the PI-RADS v2 score combined with PSA density trying to decrease the number of unnecessary prostatic biopsies in biopsy naïve and initial benign prostatic biopsy, respectively. Materials and methods: A total of 1,098 patients who underwent mpMRI at our hospital before a prostate biopsy and who underwent their second prostate biopsy with an initial benign negative prostatic biopsy or their first prostate biopsy were included. We found factors associated with clinically significant prostate cancer. And we determined the predictive values through stratifying biopsy outcomes by prior biopsy history and PI-RADS score combined with PSAD. Results: The median age was 65 years(IQR 59-70), and the median PSA was 5.1 ng/mL(IQR 3.8-7.1). The multivariate logistic regression analysis revealed that age, prostate volume, PSA density and PI-RADS score were independent predictors of csPca. In biopsy naïve group, 2 patients(4%) with PI-RADS scores of 1 or 2 had csPca and 7 patients(7%) with with PI-RADS score of 3 had csPca. In prior biopsy negative group, 2 patients(3%) with PI-RADS scores of 1 or 2 had csPca and 7 patients(6.5%) with with PI-RADS score of 3 had csPca. Clinically significant prostate cancer detection rate was 2.0%, 6.0% at PSA density of <0.15 ng/mL/mL, 0.15-0.3 ng/mL/mL among patients with PI-RADS score of 3 in biopsy naïve group. Also, csPca detection rate was 1.8%, 3.6% at PSA density of <0.15 ng/mL/mL, 0.15-0.3 ng/mL/mL among patients with PI-RADS score of 3 in prior biopsy negative group. Conclusion: The combination of PI-RADS v2 score and PSA density could be helpful when practitioner decide whether to perform prostate biopsy or not. keywords : prostate biopsy, PI-RADS score, PSA density