目的:探讨多参数MRI PI-RADS评分1～2分患者前列腺癌及有临床意义前列腺癌(CsPCa)的检出率，分析该类患者诊断前列腺癌的危险因素。方法:回顾性分析2011年7月至2018年6月行多参数MRI检查并行经直肠12针前列腺系统穿刺的196例患者的临床资料。患者年龄(66.6±9.0)岁，中位前列腺特异性抗原(PSA) 7.44(4.93，10.98)ng/ml，中位前列腺体积63(43，78)ml。196例PI-RADS评分1～2分；28例PSA4 ng/ml。前列腺癌如满足以下任一条：PSA密度>0.15 ng/mln 2, Gleason评分>6分，≥3针阳性，肿瘤≥50%穿刺长度，则诊断为CsPCa。分析前列腺癌及CsPCa的危险因素，单因素分析采用n χ2检验或Fisher’s确切概率法，多因素分析采用logistic回归。n 结果:196例中42例(21.4%)病理证实为前列腺癌，其中30例(15.3%)为CsPCa。多参数MRI诊断前列腺癌的阴性预测值为78.6%(154/196)，诊断CsPCa的阴性预测值为84.7%(166/196)。单因素分析结果显示，患者年龄、PSA密度越高，前列腺癌阳性率越高；年龄、PSA、PSA密度越高，f/tPSA越低，则CsPCa的比例越高，差异均有统计学意义(n P0.15 ng/mln 2(n OR＝2.94，95%n CI 1.45～5.95，n P70岁(n OR＝2.49，95%n CI 1.22～5.07)、f/tPSA0.15 ng/mln 2(n OR＝5.77，95%n CI 1.96～16.96)是CsPCa的独立危险因素(均n P0.15 ng/mln 2是前列腺癌的独立危险因素；CsPCa检出率为15.3%，年龄>70岁、f/tPSA0.15 ng/mln 2是其独立危险因素。n “,”Objective:To evaluate the cancer detection rate in patients with multiparametric magnetic resonance imaging (mpMRI) PI-RADS 1-2 prior to initial biopsy, and analyze the risk factors of prostate cancer.Methods:A total of 196 patients undergoing initial prostate biopsy between July 2011 and June 2018 were retrospectively analyzed. According to ESUR PI-RADS system, the patients’ PI-RADS score was 1 and 2, with the mean age of 66.6±9.0 years, and the median PSA 7.44 ng/ml. Twenty-eight patients were enrolled with PSA<4 ng/ml but with abnormal directeral rectun examination. The rest 168 patients were enrolled with elevated PSA. According to the Epstein prostate risk classification criteria, clinically insignificant prostate cancer was defined as: PSA density ≤0.15 ng/mln 2, Gleason score≤6, less than 3 positive needles, 0.15 ng/mln 2(n OR=2.94, 95%n CI 1.45-5.95) was independent risk factor of prostate cancer.Ages over 70 years(n OR=2.49, 95%n CI 1.22-5.07), PSA ratio0.15 ng/mln 2(n OR=5.77, 95%n CI 1.96-16.96) were independent risk factors of CsPCa (n P<0.05).n Conclusions:The detection rate of prostate cancer was 21.4% in patients with elevated PSA or abnormal digital prostate examination but with PI-RADS score of 1-2. Higher age and PSA density were associated with higher risk of prostate cancer. The detection rate of CsPCa was 15.3%. Ages over 70 years, PSA ratio0.15 ng/mln 2 were independent risk factors of CsPCa.n