A randomised trial comparing two protocols for transrectal prostate repeat biopsy: six lateral posterior plus six anterior cores versus a standard posterior 12-core biopsy

Objective: To test the hypothesis that a combination of 6 posterior and 6 anterior cores detects more cancer than 12 posterior cores at a repeat transrectal prostate biopsy in men who have had one previous benign systematic biopsy. Patients and methods: Three hundred and forty men with persistently raised serum PSA were randomly allocated 1:1 to either a standard 12-core biopsy (12 cores from the lateral peripheral zone through a side-fire biopsy canal) or an experimental 12-core biopsy protocol with 6 anterior cores through an end-fire biopsy canal and 6 cores from the lateral peripheral zone through a side-fire biopsy canal. All biopsies were obtained transrectally with ultrasound guidance. The primary endpoint was cancer detection. Secondary endpoints were detection of ISUP Grade Groups/Gleason Grade Group ≥2 cancer, total biopsy cancer length and complications leading to medical intervention. Results: Prostate cancer was detected in 42/168 men (25%) in the experimental biopsy group and in 36/172 (21%) in the standard biopsy group (p = 0.44). The corresponding proportions for Gleason score ≥7 were 12% and 7% (p = 0.14). Median total cancer length was 4 (inter quartile range [IQR] = 1.5 − 6) mm in the end-fire group and 3 (IQR = 1.3 − 7) mm in the side-fire group. Ten men in the end-fire group and three in the side-fire group had a medical intervention for biopsy-related complications (p = 0.05). Conclusion: The biopsy protocol that included six end-fire anterior cores did not detect more cancer and was associated with more complications.