1. From the Department of Radiology (Y. Nakai, W.G., R.K., O.A.), Hepato-Biliary-Pancreatic Surgery Division, Department of Surgery (Y. Nishioka, J.A., K.H.), and Department of Pathology (H.A., T.U.), Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.