Linac radiosurgery for brain metastasis of melanoma.

PURPOSE

To evaluate the efficacy and toxicity of stereotactic radiotherapy in the treatment of brain metastases of melanoma.

PATIENTS AND METHODS

From 1994 to 2001, 25 patients presenting with 61 metastases of cutaneous melanoma were treated with radiosurgery. Median age was 47 years (range: 25-73 years) and median Karnofski performance status 80 (range: 50-100). Twenty patients had one radiosurgery, 5 had two or three. Median metastasis diameter was 21 mm (range: 6-54.4 mm), and median metastasis volume was 1.7 cm(3) (range: 0.4-25.6 cm(3)). Irradiation was delivered by a linear accelerator. Median minimal dose was 14.1 Gy (range: 10-19.4 Gy), and median maximal dose was 20.5 Gy (range: 16-48 Gy).

RESULTS

Mean follow-up was 12.6 months (range: 1-85 months). Five metastases progressed (9.8%), 2-12 months after radiosurgery. Three-, 6- and 12-month local control rates were 95 +/- 3, 90 +/- 5 and 84 +/- 7%, respectively. By univariate analysis, only absence of extracranial tumor was a prognostic factor of local control. Three-, 6- and 12-month brain-disease-free survival rates were 75 +/- 9, 68 +/- 11 and 38 +/- 13%, respectively. According to univariate analysis, only the Score Index for Radiosurgery in brain metastases (SIR) was a prognostic factor of brain-event-free survival (p = 0.03). Median survival was 8 months. Three-, 6- and 12-month overall survival rates were 75 +/- 9, 53 +/- 10, and 29 +/- 10%, respectively. According to univariate analysis, extracranial controlled disease status (p = 0.03), and SIR (p = 0.04) were prognostic factors for overall survival. According to multivariate analysis, none was an independent prognosticator for overall survival. Complications were minimal.

CONCLUSION

Radiosurgical treatment of brain metastases of melanoma is effective and accurate. The use of radiosurgery alone is an appropriate management strategy for many patients with brain metastases of melanoma.