1. Laboratory of Histopathology and Cytopathology, Department of Laboratory Sciences, Gunma University Graduate School of Health Sciences, Maebashi, Gunma 371‑8514, Japan
2. Department of Pathology, Public Tomioka General Hospital, Tomioka, Gunma 370‑2316, Japan
3. Department of Pathology, Gunma University Hospital, Maebashi, Gunma 371‑8514, Japan