Fibromatosis is a locally aggressive, proliferative fibroblastic lesion affecting musculoaponeurotic structures, most often in the limbs and trunk. Intracranial fibromatosis is extremely rare and requires aggressive treatment to prevent recurrence. Case Description - We present the case of a 20 year old woman with aggressive skull base fibromatosis. The lesion extended through the sphenoid, ethmoid sinus and nasal cavity, destroying the right roof of the orbit and penetrating in anterior skull base. A combined anterior craniofacial approach was performed; complete resection with surgical margin was impossible due to the localization of the tumor and relation to important neurovascular structures. Complete resection with surgical margin is often impossible because of its widely infiltrative nature. Radiotherapy and chemotherapy are often required to improve local control of the lesion.
