1. From the Department of Radiology, Breast Imaging Section, University of Pennsylvania, Perelman School of Medicine, Hospital of the University of Pennsylvania, 3400 Spruce St, 1 Silverstein, Philadelphia, PA 19104-4283 (E.S.M., S.P.W., M.D.S., E.F.C.); and General Medicine Division, Massachusetts General Hospital, Harvard Medical School, Boston, Mass (A.M.M.).