Falcine and parasagittal chondrosarcomas.

Intracranial chondrosarcomas are primary cartilaginous neoplasms that represent 6% of all skull base tumors. Intracranial extraskeletal chondrosarcomas are more rare, often arising from the meninges at the falx, tentorium, or cerebral convexity. They are generally characterized as classical or mesenchymal, with the latter associated with worse outcomes. We present our institutional series of falcine and parasagittal chondrosarcomas along with a review of the literature. Although skull base chondrosarcomas pose significant challenges due to their invasive biology and proximity to vital brainstem structures and cranial nerves, intracranial extraskeletal chondrosarcomas are generally associated with a good prognosis. Our review of the literature identified 29 patients with falcine and parasagittal chondrosarcomas. There were six recurrences, five among patients with the mesenchymal subtype and one in a patient with the classical subtype. All deaths occurred in patients with the mesenchymal subtype. Management of skull base chondrosarcomas is controversial but extraskeletal intracranial tumors can generally be managed by surgical resection alone. Treatment should be tailored to the biology of the tumor, with radiation therapy reserved for patients with the mesenchymal subtype.