Integration of gamma knife surgery in the management of cerebral metastases from melanoma.

The aim of this study was to investigate the effect of gamma knife surgery on the local control of cerebral metastases from melanoma and to assess survival. In 29 patients, 105 of 178 cerebral metastases were treated with gamma knife surgery. Only five patients had metastases confined to the brain. Of the 96 metastases with magnetic resonance imaging follow-up, 61.5% regressed by more than 50% of the pretreatment volume, 25% regressing by more than 90% and 13.5% completely. The median survival from gamma knife surgery was 5.7 months (longest survival, 38 months). In multivariate analyses, a larger number of lesions requiring treatment (P < 0.001), recursive partitioning analysis class (P = 0.009) and a long time interval from initial melanoma diagnosis to detection of cerebral metastases (P = 0.001) influenced survival. It can be concluded that gamma knife surgery is a useful adjunct in the management of cerebral metastases from melanoma and has a significant impact on local control. Its greatest potential may be achieved in conjunction with systemic chemotherapy, especially in the presence of extracerebral metastases.