1. Department of Oncology, Kameda Medical Center, Kamogawa, Chiba 296-8602, Japan
2. Department of Gastroenterology and Gastrointestinal Oncology, National Cancer Center Hospital East, Kashiwa, Chiba 277-8577, Japan
3. Department of Gynecology, Kameda Medical Center, Kamogawa, Chiba 296-8602, Japan
4. Department of Anatomic and Diagnostic Pathology, Dokkyo Medical University School of Medicine, Shimotsuga, Tochigi 321-0293, Japan