Chondromyxoid fibroma of the mandible: report of a case

Introduction

The chondromyxoid fibroma is an exceedingly rare benign tumor, representing less than 1% of all bone tumors. It has a slight male preponderance; males are affected approximately 1.5 times more often than females. Though typically affecting patients during the second and third decades of life, reports of patients who are 50 years and older do exist. With a distinct predilection for the metaphyseal regions of the long bones of the lower extremities, the chondromyxoid fibroma has also commonly been reported in the small bones of the feet and the ilium. Much less common are lesions of the craniofacial bones, ribs, spine, and short tubular bones of the hands and feet. Herein, a case of chondromyxoid fibroma of the mandible is reported.

Case Report

A multilocular radiolucent lesion was noted in the left mandible of a 48-year-old male, and submitted to the UKCD Oral Pathology Biopsy service with a clinico-radiographic differential diagnosis including ameloblastoma and odontogenic keratocyst. Upon histopathologic examination, a fragmented, but pseudolobulated mass composed of myxomatous and chondroid areas with intervening zones of hypercellular mononuclear tissue containing sparse multinucleated giant cells, was appreciated. The myxoid areas contained both plump and stellate spindled cells at the periphery. Immunohistochemistry for MDM2 was negative, essentially excluding the possibility of a low-grade central osteosarcoma.

Conclusions

Presentation of this case represents a significant addition to the literature of this rare entity occurring in a distinctly uncommon location, and highlights this entity as a consideration in the histopathological differential diagnosis of myxoid lesions of the craniofacial bones.