MRI and ultrasound-guided prostate biopsy using soft image fusion

Transrectal ultrasound (TRUS)-guided random biopsies is the gold standard when diagnosing prostate cancer. A new 3D system with organ tracking, allows accurate targeted biopsies using magnetic resonance imaging (MRI) and TRUS soft image fusion. The aim of the study was to evaluate the accuracy of targeted biopsies.

Retrospective study of 90 consecutive patients with suspected prostate cancer underwent MRI prior to biopsy using 3D T2w and diffusion weighted imaging (12 min protocol). Suspicious tumours (MRI targets) were highlighted on axial T2w images and classified as high, moderate or low degree of cancer suspicion. Navigation system: Urostation(Koelis®, Grenoble, France). Primary endpoint: Rate of successful targeted biopsies. Positive biopsies with Gleason score.

MRI was positive in 80/90 (89%) patients, in which 115 MRI targets were identified and biopsied. There were 112/115 (97%) successful biopsies inside target, and 60/115 (52%) targets were positive for cancer. Positive biopsies according to degree of cancer suspicion were: high 50/55 (91%), medium 6/22 (27%) and low 4/38 (10%). All MRI-negative patients had negative random biopsies.

The high rate (97%) of successful biopsies in this study indicates that targeted biopsies using MRI and TRUS soft image fusion technique might be an accurate method.