Malignant Fibrous Histiocytoma in the Infratemporal Fossa / 대한구강악안면방사선학회지

ABSTRACT

Malignant fibrous histiocytoma is one of the most common soft tissue sarcomas in late adult life, but its incidence in oral and maxillofacial region is extremely rare. We report a case of malignant fibrous histiocytoma which occurred in the infratemporal fossa. Conventional radiograph of this case showed an ill-defined radiolucent lesion in the alveolar bone of the right maxillary first molar area, the lateral wall of the maxillary sinus, and the ascending ramus of mandible. MRI demonstrated well defined mass of intermediate signal intensitiy in T1 weighted images but T2 weighted images showed two distinctive regions of different characteristics. Infratemporal portion of the lesion was of hyperintense signal but under that region, the signal intensity decreased clearly, which might mean this case composed of two different subtypes, though it couldn't be confirmed by histopathological examination. Biopsy was taken in the only soft tissue of the maxillary posterior alveolar region and confirmed the lesion as the storiform-pleomorphic type of malignant fibrous histiocytoma. Histopathological subtype was well consistent with the relatively aggressive imaging findings of that region. We expect more detailed analysis of the nature of malignant fibrous histiocytoma with improvement of the imaging modality and the identification of the relationship between diagnostic imaging and histopathologic findings.