1. Department of Otorhinolaryngology-Head and Neck Surgery; Kitasato University School of Medicine; Sagamihara Kanagawa Japan
2. Department of Gastroenterology; Kitasato University School of Medicine; Sagamihara Kanagawa Japan
3. Department of Pathology; Kitasato University School of Medicine; Sagamihara Kanagawa Japan
4. Kitasato Clinical Research Center; Kitasato University School of Medicine; Sagamihara Kanagawa Japan