From the North East Japan Study Group; Tohoku University, Graduate School of Medicine and School of Medicine; Miyagi Cancer Center; Kesennuma City Hospital, Miyagi; Saitama Medical University, Saitama; Kanto Medical Center NTT EC; Nippon Medical School, Tokyo; Tsuboi Cancer Center Hospital, Fukushima; Hokkaido University, Graduate School of Medicine, Hokkaido; Yokohama City University, Kanagawa, Japan. (At 2009-03-20)