1. From the Department of Radiology (A. Pourvaziri, J.C., A.K.), Harvard Catalyst Biostatistics Consulting Unit (J.L.), and Department of Urology (D.S.), Massachusetts General Hospital, 55 Fruit St, Boston, MA 02114; Department of Radiology, Brigham and Women’s Hospital, Boston, Mass (A. Parakh); and Department of Radiology, University of Washington, Seattle, Wash (B.E.).