Cranial vault metastasis of giant cell tumor.

Giant cell tumors are benign bony tumors involving the epiphysis of long bones. Here, we present a case of giant cell tumor involving the parietal bone that had metastasized from the sacrum. A 36-year-old healthy woman presented to neurosurgery clinic in April 2005 reporting a "bump" over the left parietal area that had been increasing in size over the past 6 months. The lesion was nontender, and the patient had no other associated neurological symptoms. As we have presented here, cranial vault metastases can occur and should be considered in a differential diagnosis of bony lesions found in this location. These distant metastases, although relatively uncommon, must be managed aggressively. Newer radiation treatments seem to be a promising favorable adjunct to wide local resection and should be investigated further for these tumors.