1. Atomic Bomb Disease Institute, Nagasaki University Division of Strategic Collaborative Research, Center for Promotion of Collaborative Research on Radiation and Environment Health Effects, , 1-12-4 Sakamoto, Nagasaki, Nagasaki 852-8523 , Japan
2. Atomic Bomb Disease Institute, Nagasaki University Department of Tumor and Diagnostic Pathology, , 1-12-4 Sakamoto, Nagasaki, Nagasaki 852-8523 , Japan
3. Department of Surgery, Sendai City Medical Center , 5-22-1 Tsurugaya, Miyagino, Sendai, Miyagi 983-0824 , Japan