The Role of MRI-US Fusion Techniques in Detection of Clinically Significant Prostate Cancer
Prostate cancer is the commonest male cancer and the second leading cause of cancer-related death in men. Over many decades, prostate cancer detection represented a continuous challenge to urologists. Although all urologists and pathologists agree that tissue diagnosis is essential especially before commencing active surgical or radiation treatment, the best way to obtain the biopsy was always the big hurdle. The heterogenicity of the tumor pathology is very well seen in its radiological appearance. Ultrasound has been proven to be of limited sensitivity and specificity in detecting prostate cancer. However, it was the only available targeting technique for years and was used to guide biopsy needle passed transrectally or transperineally. Magnetic Resonance Imaging (MRI) has revolutionized the process with the advent of its multiparametric imaging (mp MRI) where the prostate is evaluated by different MRI techniques and the likelihood of the detected lesion is scored using the new prostate imaging-reporting and data system (PIRADS) scoring. Despite the improved detection of clinically significant prostate cancer by mpMRI, the ideal way to target the area of suspicion detected by mpMRI is the next level of challenge. In this review article, we will discuss the recent methods of targeting and focus on the different platforms used to integrate the mpMRI static images with the real-time US scanning in what is called (US-MRI fusion techniques).