Contributed by Linda M. Dallasta, MD, PhD and Ronald L. Hamilton, MD
Published on line in April 1998
The patient was an 11 year old Caucasian female who was found by her mother two weeks prior to admission to have a firm bump on her head over the left frontal region. The patient denied headache, nausea, vomiting, dizziness, and lump tenderness but was noticed to have papilledema upon examination. She subsequently underwent a left frontoparietal craniotomy for tumor resection.
A CT scan showed left frontoparietal bony erosion and thickening by a large extra-axial tumor mass which extended into the brain. The MR scan showed a large, 7 cm, left frontoparietal mass which appeared to arise from the region of the dura and bone and which extended both intra- and extra-cranially. The overlying bone was markedly thickened with an almost spiculated appearance. There was marked gadolinium enhancement of the intracranial portion of the tumor with lesser enhancement of the extra-cranial portion. A large feeding vessel from the meninges was noted to traverse the intracranial portion of the mass. Ipsilateral compression of the lateral ventricle with a slight midline shift was also seen. Given the combination of imaging characteristics and large feeding vessel, the lesion was suspicious for a meningioma. However, due to the bony appearance, a primary chondrosarcoma or PNET or, less likely, a metastatic tumor such as a neuroblastoma, were also considered in the differential diagnosis.