Magnetic Resonance Imaging–guided Active Surveillance of Prostate Cancer: Time to Say Goodbye to Protocol-based Biopsies

Traditional protocols for active surveillance (AS) are commonly based on digital rectal examination, prostate-specific antigen (PSA), and standard transrectal biopsy, meaning that initial classification errors and inaccurate lesion monitoring can occur. Protocol-based biopsies are performed to assess changes in cancer grade and extent at prespecified intervals, but this approach represents a barrier to AS adherence and tolerability. There is evidence to support the use of magnetic resonance imaging (MRI) during AS, as this technique (associated with favourable PSA kinetics) offers an opportunity to follow patients on AS without the need for routine, protocol-based biopsies in the absence of signs of radiological progression provided that image quality, interpretation, and reporting of serial imaging are of the highest standards. PATIENT SUMMARY: In this report we looked at the role of magnetic resonance imaging (MRI) scans in avoiding unnecessary prostate biopsies for patients being monitored for low- or intermediate-risk prostate cancer. We conclude that patients on active surveillance can be monitored with MRI scans over time and that biopsies could be used only when there are changes on MRI or a rising prostate-specific antigen (PSA) not explained by an increase in prostate size.