The effect of palliative radiation therapy on epidural compression due to metastatic malignant melanoma.

The efficacy of palliative radiation therapy in the treatment of spinal cord and cauda equina compression due to metastatic malignant melanoma was evaluated in 38 sites in 35 patients treated between 1970 and 1990. All patients had radiographic documentation of epidural compression. The median dose of radiation therapy was 2850 cGy (range, 500 to 4000 cGy), with daily fractions ranging from 200 to 800 cGy. Twenty-eight sites in 26 patients were evaluable 1 month after completion of radiation therapy, and symptoms responded completely in 11 of 28 (39%) sites. Fourteen sites (46%) showed a partial response of symptoms. Response lasting until death was documented in 21 of 26 patients (81%). Patients receiving a total dose of 3000 cGy or greater were more likely to achieve a complete response than those receiving less than 3000 cGy (62% versus 20%) by univariate (P = 0.025) and multivariate (P = 0.048) analyses. A treatment program of radiation therapy and corticosteroids is effective in palliating the symptoms of epidural compression due to metastatic malignant melanoma. It is recommended to deliver an accelerated course of radiation therapy to a dose of 3000 cGy or greater without exceeding spinal cord tolerance (e.g., 3000 cGy in ten fractions at 300 cGy per fraction).