When to Order an MRI in the Initial Evaluation and Management of Prostate Cancer.

Prostate cancer remains the only solid tumor diagnosed using transrectal ultrasound-guided sampling of the gland, and not an image-based, lesion-directed approach. This technique has limitations in that it underdiagnoses clinically significant disease and overdiagnoses indolent tumors resulting in overtreatment of patients. Technical advances in MRI in the last decade have made this method the preferred imaging modality for prostate anatomy and for risk assessment of prostate cancer. As of 2018, the indications for MRI in the diagnosis and risk assessment of prostate cancer have expanded from preoperative evaluation to the pre-biopsy setting, as well as for surveillance protocols. This article summarizes the current role of multiparametric MRI in the diagnosis, risk assessment, and treatment of prostate cancer.