1. Department of Otolaryngology‑Head and Neck Surgery, Kurume University School of Medicine, Kurume, Fukuoka 8300011, Japan
2. Department of Diagnostic Pathology, Kurume University School of Medicine, Kurume, Fukuoka 8300011, Japan
3. Department of Pathology, Kurume University School of Medicine, Kurume, Fukuoka 8300011, Japan