INTRACRANIAL SCHWANNOMA PRESENTING AS A SUBFRONTAL TUMOR - CASE-REPORT

OBJECTIVE AND IMPORTANCE: Intracerebral schwannomas not associated wit h cranial nerves account for less than 1% of surgically treated schwan nomas of the central and peripheral nervous system. Subfrontal schwann omas are extremely rare, with only 15 cases reported to date. CLINICAL PRESENTATION: A 33-year-old man presented with a 4-month history of p rogressive headaches and lethargy. Radiographic studies revealed a lar ge subfrontal tumor thought to be a meningioma preoperatively. INTERVE NTION: The patient underwent a craniotomy for resection of his tumor. Intraoperatively, a large extra-axial tumor arising from the floor of the left frontal fossa was encountered. CONCLUSION: Microscopic examin ation of the tumor revealed a schwannoma. Several theories on the poss ible origin of intracerebral schwannomas have been considered. Because of the age of the patient at presentation, many authors have postulat ed a developmental origin for these lesions. However, extra-axial schw annomas not associated with cranial nerves often present later in life , suggesting a different pathogenesis for this subgroup.