Recent progress in MRI-ultrasound fusion for guidance of targeted prostate biopsy

Prostate cancer is currently diagnosed by prostate biopsy performed by the transrectal ultrasound-guided technique. However, overdetection of clinical insignificant tumours and missed detection of clinical significant tumours have become problematic. MRI of the prostate, particularly if performed with multiparametric imaging, is capable of detecting clinical significant prostate cancer, which has brought the opportunity to use those images as targets for needle biopsy. Three methods of fusing MRI for targeted biopsy have been recently described: MRI-ultrasound fusion, MRI-MRI fusion (′in-bore′ biopsy) and cognitive fusion. Fusion of MRI with ultrasound allows urologists to progress from blind, systematic biopsies to biopsies, which are mapped, targeted and tracked. In the future, MRI-ultrasound fusion for lesion targeting is likely to result in fewer and more accurate prostate biopsies than the present use of systematic biopsies with ultrasound guidance alone. Key words: Prostatic neoplasms; Biopsy; Multi-parametric MRI; MRI-ultrasound fusion; Targeted biopsy