Intracranial extraskeletal myxoid chondrosarcoma: case report and review of the literature

Abstract

Background: We describe a patient with an intracranial extra skeletal myxoid chondrosarcoma (EMC), an unusual neoplasm of the deep soft tissues of the extremities. Very rarely are they localised as an intracranial lesion, and we believe it is very important to accurately distinguish EMC from other intracranial tumours such as classical or "skeletal" chondrosarcomas, mesenchymal chondrosarcoma, enchondroma, and myxoid tumours (chordoma, and chondromyxoid fibroma) in order to determine their prognostic implications. Furthermore, this case presents with the second local recurrence, higher-grade cellular areas, such an event has never been reported in intracranial cases.

Method: A 17 year-old female presented with tonic and clonic seizures, episodic left hemiplegia and intense right-sided headaches. Computed tomography and magnetic resonance of the skull showed a right fronto-parietal cortical lesion. Complete surgical excision of the lesion through a right parieto-temporal craniotomy was performed. The tumoral lesion recurred locally twice (16 and 19 months after the initial surgery respectively).

Findings: First and second surgical specimens where diagnosed as extra skeletal myxoid chondrosarcoma. Microscopically, the third specimen (second local recurrence) showed abrupt transition from areas of conventional myxoid chondrosarcoma to high-grade cellular areas with fusiform features.

Interpretation: Extra skeletal myxoid chondrosarcoma is very rarely described as an intracranial lesion. Reference on this topic is very confusing as there is no clear-cut distinction between skeletal chondrosarcomas with prominent myxoid matrix and extra skeletal myxoid chondrosarcoma which is a definite entity first defined by Enzinger and Shiraki in 1972 in deep soft tissues of the extremities. We review the cases reported in the literature with the diagnosis of myxoid chondrosarcoma either of extra skeletal origin or with skeletal attachment, and analyse their clinic and pathological features.