499 A Retrospective Audit on Detection Rate of Clinically Significant Cancer Among MP-MRI Targeted Biopsy – A Single Centre Experience

Abstract

Abstract Men with high serum prostate specific antigen (PSA) typically undergo standard transrectal ultrasound-guided prostate biopsy (TRUS-biopsy) during which 10 to 12 cores are obtained. TRUS-biopsy can cause side-effects including bleeding, pain, and infection. Multi-parametric MRI (MP-MRI) used as a triage test might allow men to avoid unnecessary TRUS-biopsy and improve diagnostic accuracy. According to the renowned PROMIS study, for clinically significant cancer, MP-MRI was more sensitive and less specific than TRUS-biopsy. In this study, we performed a single centre, retrospective audit on the detection rate of clinically significant cancer among MP-MRI targeted biopsy and compare it with the standard TRUS biopsy. Clinically significant cancer is defined as Gleason score ³ 4 +3 or a maximum cancer core length 6mm or longer. Besides, we also compare the rate of clinically significant cancer in MP-MRI targeted biopsy against the PROMIS study. Through this audit, we found that in 2019, there is a 54% (60 out of 112 patients) of clinically significant cancer in MP-MRI biopsy and 41% (26 out of 64 patients) of clinically significant cancer among standard TRUS biopsy. Comparing it with the PROMIS study in which clinically significant cancer was detected in 38% in the MP-MRI targeted biopsy group and 26% in the standard-biopsy group, the adjusted difference in our study (13%) is similar to PROMIS study which is 12%. In conclusion, our study reaffirms that MP-MRI targeted biopsy reduce over-diagnosis of clinically insignificant prostate cancer and improve detection of clinically significant cancer.