MDPI Acta Medica Okayama 2571-841X 4 1 2021 A Case Report of Spindle Cell Carcinoma with Osteoid and Cartilage Formation in the Tongue 5 EN Sawako Ono Department of Pathology, Okayama University Hospital Takuma Makino Department of Otolaryngology Head and Neck Surgery, Okayama University Hospital Hiroyuki Yanai Department of Pathology, Okayama University Hospital Hotaka Kawai Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kiyofumi Takabatake Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Keisuke Nakano Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kenji Nishida Department of Pathology, Okayama University Hospital Kohei Taniguchi Department of Pathology, Okayama University Hospital Tomohiro Toji Department of Pathology, Okayama University Hospital Hitoshi Nagatsuka Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tadashi Yoshino Department of Pathology, Okayama University Hospital Spindle cell carcinoma (SCSCC) with osteoid and/or cartilage formation in the head and neck is rare; only one case was reported in the tongue. Herein, we report an SCSCC with osteoid and cartilage formation of the tongue developed in an 85-year-old man, and then review the report. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2571-841X 4 1 2021 A Case Report of Primordial Odontogenic Tumor That Required Distinction from a Dentigerous Cyst 4 EN Sawako Ono Department of Pathology, Okayama University Hospital Hotaka Kawai Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shintaro Sukegawa Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kiyofumi Takabatake Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Keisuke Nakano Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hitoshi Nagatsuka Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tadashi Yoshino Department of Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Primordial odontogenic tumor (POT) is a rare odontogenic tumor characterized by a variably cellular loose fibrous tissue with areas similar to the dental papilla and covered by cuboidal to columnar epithelium. We herein report a case of POT in a 14-year-old boy. Computed tomography (CT) exhibited a round cavity with a defined cortical border circumscribing the tooth of the second molar. However, the gross finding was a solid mass, not a cyst. Histologically, the tumor consisted of dental papillalike myxoid connective tissue covered by columnar epithelium. Therefore, although the clinical diagnosis was dentigerous cyst (DC), we diagnosed POT based on histologic findings. Clinical findings of POT resemble DC, but the clinical behavior of POT is different to DC, such as cortical expansion and root resorption of teeth. Therefore, histological differentiation of POT from DC is critical for accurate diagnosis. No potential conflict of interest relevant to this article was reported.