1. Spontaneous extraskeletal osteosarcoma in the neck skeletal muscle of a Crlj:CD1 (ICR) mouse
- Author
-
Kazuto Hashimoto, Shiori Chiba, Hiroaki Nejishima, Kanata Ibi, and Naomi Koyama
- Subjects
musculoskeletal diseases ,Extraskeletal Osteosarcoma ,Pathology ,medicine.medical_specialty ,040301 veterinary sciences ,CD1 ,Vimentin ,Case Report ,extraskeletal osteosarcoma ,Toxicology ,Bone tissue ,Pathology and Forensic Medicine ,0403 veterinary science ,03 medical and health sciences ,0302 clinical medicine ,medicine ,mouse ,biology ,Osteoid ,business.industry ,Skeletal muscle ,neck skeletal muscle ,04 agricultural and veterinary sciences ,spontaneous tumor ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Osteocalcin ,biology.protein ,Immunohistochemistry ,business - Abstract
Extraskeletal osteosarcoma is extremely rare in humans and animals, especially in rodents. This is the first case report on spontaneous extraskeletal osteosarcoma in the neck skeletal muscle of a Crlj:CD1 (ICR) mouse (36 weeks, dead). Necropsy revealed a solid white mass located in the neck skeletal muscle (scalenus muscle). Histological examination showed that the tumor consisted of atypical polygonal cells, a small osteoid clump, and bone tissue. Mitotic figures were observed. Serial sections showed that neoplastic cells lacked clear invasive proliferation to adjacent normal skeletal muscle and continuity with normal bone tissue. Immunohistochemical analysis showed that the neoplastic cells were positive for osteocalcin, osterix, vimentin, and S-100. Based on these results, the tumor was diagnosed as extraskeletal osteosarcoma in the neck skeletal muscle.
- Published
- 2021