Cancer - Prostate(구연) (E-146) 표적 생검 음성을 보이는 PI-RADS 4점과 5점 전립선암 환자에서 체계적 생검 양성의 위험인자 부산대학교 의과대학 비뇨의학교실¹ 김경환¹, 박지훈¹, 강병진¹, 박시균¹, 이권경¹, 구자윤¹, 하홍구¹ Objectives We aimed to investigate the risk factors for positive systemic prostate biopsy in the patients showing negative targeted biopsy despite of prostate imaging-reporting and data system (PI-RADS) 4-5 lesions on multiparametric MRI (mpMRI). Materials and Methods From Apr, 2017 to Apr, 2020, 240 patients with PI-RADS 4 and 5 lesions on preoperative mpMRI scans underwent the concurrent systemic and targeted prostate biopsy. We identified 27 patients who had positive systemic biopsy but negative targeted biopsy. The logistic regression analysis was used to identify the risk factors for positive systemic biopsy in the patients with negative targeted biopsy. Statistical significance was considered at p < 0.05. Results Median age and prostate specific antigen (PSA) level were 67 years and 7.88 ng/ml, respectively. Mean biopsy core number was higher and positive rate was lower in systemic biopsy than targeted biopsy (11.6 vs. 3.7 and 0.29 vs. 0.48, respectively). PI-RADS 4 and 5 index lesions were observed in 139 (57.9%) and 101 (42.1%), respectively. Out of 240 patients, 138 (57.5%) patients had single prostatic lesion with PI-RADS 4 or 5 on mpMRI scans. Mean size of index lesion was 15.7 mm. In the logistic regression analysis, PSA was the only significant and inversely correlated predictor for positive systemic biopsy in the patients with negative targeted biopsy (p = 0.015 and odds ratio = 0.75, respectively). Conclusion Lower PSA level was a significant risk factor for positive systemic prostate biopsy in PI-RADS 4 and 5 patients showing negative targeted biopsy. keywords : Biopsy, PI-RADS score, Prostate cancer