Single brain metastases from unknown primary malignancies in CT-era.

Cerebral metastases account for about half of all intracranial neoplasms. In 33%-66% they represent the first sign of a systemic tumor. We report our experience in 100 patients with solitary brain metastasis from unknown primary malignancies treated between 1976 and 1988. All patients were treated surgically and 81 also received radiotherapy and chemotherapy. Postoperative mortality was 6%. Mean survival in those patients with unknown primary tumor at intracranial surgery was 15.3 months as compared to 31.6 months in those in whom it remained unidentified during life. The usual cause of death was growth of the systemic cancer.