Evaluation of the PI-RADSv2 classification in a cohort of patients who underwent a prostate fusion biopsy

INTRODUCTION: Prostate Fusion biopsy (MRI + prostate ultrasound) is described in literature as superior to classic random transrectal biopsy in order to identify suspicious lesion. OBJECTIVES: To evaluate the Prostate Imaging Reporting and Data System (PI-RADS) proposed by the European Society of Urogenital Radiology (ESUR) for detection of prostate cancer by multiparametric MRI in a consecutive cohort of patients with MRI and transrectal ultrasound prostate fusion-guided biopsy. MATERIAL AND METHODS: 87 patients with suspected Prostatic Cancer on prostate MRI underwent fusion transperineal prostate biopsy in our Department. 37 patients had at least one prior negative classic prostatic transrectal biopsy. Clinically significant tumor was described as Gleason 7(3+4) or higher. The Chi-square test was used to analyze the relationship between prostate cancer and the different PIRADS stages, as well as logistic regression and linear trend tests, comparing the proportions using measures of association intensity. We use the HITACHI Real-Time Virtual Sonography (HI-RVS) system, and the STATA/IC v. 14.2 software for statistical analysis. RESULTS: 64.37% patients had tested positive for malignancy. Median age 67.89 years old. Median PSA 9.15 ng/ml, and average prostate volume was 54.05 cc. 124 suspicious lesions were described in prostate MRI (25% PIRADS III, 57% PIRADS IV and 17% PI-RADS V). 5/31 lesions PIRADS III, 47/71 PIRADS IV and 18/22 PIRADS V were positive for malignancy, with a statistically significant linear relationship between PIRADS and malignancy (p<0.001) - HR 4.10 (CI 95% 1.81 to 9.32) for PIRADS IV and HR 5.07 (CI95% 2.22 to 11.59) for PIRADS V vs. PIRADS III. 3.23% lesions PIRADS III, 32.39% PIRADS IV and 63.64% PIRADS V corresponded to significant tumors. A statistically significant association between PIRADS and significant tumors (p<0.001) - HR 10.04 (CI95% 1.42 to 71.09) for PIRADS IV and HR 19.73 (CI95% 2.80 to 139.18) for PIRADS V vs PIRADS III was observed -. CONCLUSION: Our results show that transperineal targeted prostate biopsy using multiparametric MRI and transrectal ultrasound fusion is a safe procedure with excellent outcomes to obtain an accurate diagnosis of prostate cancer. Fusion biopsy has the potential to improve the diagnosis of malignancy and clinically significant tumors while reducing overdiagnosis.