Mutiparametric MRI – Local staging of prostate cancer and beyond
Accurate local staging is critical for treatment planning and prognosis in patients with prostate cancer. The primary aim is to differentiate between organ-confined and locally advanced disease with the latter carrying a worse clinical prognosis. Multiparametric (mp) MRI is the imaging modality of choice for local staging of prostate cancer and has an incremental value in assessing pelvic nodal disease and bone involvement. It has shown superior performance compared to traditional staging based on clinical nomograms and provides additional information on the extent and site of the disease. MRI has a high specificity for diagnosing extracapsular extension, seminal vesicle invasion and lymph node (LN) metastases, however, sensitivity remains poor. As a result, extended pelvic LN dissection remains the gold standard for assessing pelvic nodal involvement, and there has been recent progress in developing advanced imaging techniques for distal staging. So called “next generation” imaging includes whole body MRI and PET-MRI imaging using prostate specific membrane antigen (68Ga-PSMA), with early promising results for the detection of LN and bone metastases. In this article, the current state of evidence supporting MRI staging in patients with prostate cancer is reviewed.