Surgical and radiosurgical management of brain metastases.

When should surgery be used? First, when there is a need to establish the diagnosis of metastatic cancer, particularly in patients who have no known primary lesion. Second, as an effective therapy in patients who have a single brain metastasis, symptomatic or recurrent metastases, or when a metastasis threatens hydrocephalus if treated with radiation alone. Surgery is probably more effective in relieving symptoms from metastases than other treatments,although formal proof of this is lacking. Stereotactic radiosurgery can replace resection when the metastases are smaller than 3 cm and symptoms can be controlled with an acceptable steroid dose. Location of larger lesions in the posterior fossa is a relative contraindication to radiosurgery. The best candidates for resection and radiosurgery are those who have good systemic control of the primary disease; older age is a relative contraindication to resection. Aggressive treatment of oligometastatic brain disease probably is underused in current U.S. practice.