Treatment of Metastatic Melanoma Using Stereotactic Body Radiosurgery

Abstract

To investigate the therapeutic effect of Stereotactic Body Radiosurgery (SBR) for the treatment of extracranial metastatic melanoma. Thirty three metastatic melanomas were treated in 19 patients. The majority were treated in the liver and lung (10 and 8 respectively). All the patients were evaluated prospectively before and after treatment. Age ranged from 41 to 81 years (mean 62) with 10 females and 9 males. Tumor volumes ranged from 2.3 to 3315 cc (mean 459.6 cc). Patients were treated with 400-800 cGy (median 600) in 3-6 fractions (median 5) for a total dose of 2000-4000 cGy (median 3000). Cancers were radiographically evaluated with contrast CT and/or MRI studies and reviewed independently by radiologists. Control of the treated cancer is defined as cessation of growth, shrinkage or disappearance of the cancer after treatment. Follow-up ranged from 1 to 57 months (mean 7.7). The overall control rate was 87.8%. Two of the 19 patients did not respond to treatment. They both had lung metastases, with one of the patients having additional liver metastases. By dose, volume, age, sex and prior treatment, there was no statistically significant difference in outcome. Melanoma metastases treated with SBR offers a generally well-tolerated, non-invasive method with a high rate of tumor control. Patients continue to be evaluated for longer follow-up, possible benefits of local control and potential survival advantage.