1. Department of Oral and Maxillofacial Surgery, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755‑8505, Japan
2. Department of Radiation Oncology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755‑8505, Japan
3. Department of Nursing, Yamaguchi University Hospital, Ube, Yamaguchi 755‑8505, Japan
4. Division of Medical Nutrition, Yamaguchi University Hospital, Ube, Yamaguchi 755‑8505, Japan