Gamma knife surgery for brain metastases in patients harboring four or more lesions: survival and prognostic factors.

Object: This study was performed to evaluate the role of gamma knife surgery (GKS) in patients with a large number (four or more) of metastatic brain lesions.

Methods: The authors retrospectively reviewed the outcome in 130 patients who underwent GKS for metastatic lesions. Eighty-four patients presented with one to three lesions (Group A) and 46 presented with four or more lesions (Group B).