1. Department of Surgery, Kyushu University Beppu Hospital, Beppu 874-0838, Japan
2. Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka University, Suita 565-0871, Japan
3. Laboratory of DNA Information Analysis, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo 108-8639, Japan
4. Department of Surgery, Fukuoka City Hospital, Fukuoka 812-0046, Japan
5. Laboratory of Functional Genomics, Department of Medical Genome Sciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa 277-8562, Japan