title: Mesenchymal chondrosarcoma of the hyoid bone: a case report.
abstract: Mesenchymal chondrosarcoma is a rare tumor that is distinctly different from classic chondrosarcoma. The prognosis of this tumor is poor, with a high incidence of locoregional and distant metastases. It shows a predilection for the head and neck, however mesenchymal chondrosarcoma of hyoid bone has rarely been reported. We experienced a case of mesenchymal chondrosarcoma of the hyoid bone in a 39-year-old woman. She underwent excision of the tumor by right hemihyoidectomy. Histologically, a combination of cellular zones composed of undifferentiated small cells and chondroid zones typically presented a bimorphic appearance. CD99 (DN16) immunohistochemical stain demonstrated that all undifferentiated small cells had strong reactivity with a distinct membranous pattern. There was microscopic tumor extension to the resection margin of the hyoid bone, however, no evidence of reccurence is noted at follow-up of 4 months with neck CT.
authors.affiliation: Department of Pathology, Inje University, Seoul Paik Hospital, Korea.
authors.forename: M
authors.initials: M
authors.lastname: Joo
authors.forename: Y K
authors.initials: YK
authors.lastname: Kang
authors.forename: H S
authors.initials: HS
authors.lastname: Kim
authors.forename: H K
authors.initials: HK
authors.lastname: Lee
authors.forename: Y K
authors.initials: YK
authors.lastname: Park
mesh_terms: D000328:Adult; D001859:Bone Neoplasms / Q000473:pathology*; D018211:Chondrosarcoma, Mesenchymal / Q000473:pathology*; D005260:Female; D006801:Humans; D006928:Hyoid Bone / Q000473:pathology*