PALLIATIVE RADIOTHERAPY OF VERTEBRAL METASTASES: COMPARISON OF PALLIATION BETWEEN DAILY 2 GY AND 3 GY PROTOCOLS

We compared retrospectively the daily 2 Gy and 3 Gy radiation schedules to evaluate which is better for palliative effectiveness in patients with vertebral metastases. The frequency and promptness of pain relief were utilized as indices of response. Seventy-three patients were divided into two groups: group I; 40 patients who received radiotherapy by a conventional scheme of 2 Gy/fraction, 5 days/week and a total dose of 50 Gy in 25 daily fractions (TDF: 80.6) and group II; 33 patients by 3 Gy/fraction, 5 days/week and a total dose of 39 Gy in 13 daily fractions (TDF: 78.2). Sufficient pain relief was obtained in 92% of group I and 88% of group II (p=0.17). Although there was no statistically significant difference in the time interval from the initiation of radiotherapy to sufficient pain relief in these groups (p=0.18), sufficient pain relief within 2 weeks was achieved in 73% of group II and 52% of group I. There were no differences in responses of motor deficits (p=0.72) or complications (p=0.78) between these groups after treatment. In conclusion, this study shows no statistical differences in sufficient pain relief, responses of motor deficits and complications between group I and group II. Thus we conclude that the daily 3 Gy schedule is better than the daily 2 Gy schedule for a palliative radiation therapy in a patient with a potentially poor prognosis because of the shorter therapeutic period. However, the daily 3 Gy schedule should be used cautiously and the total dose of less than 35 Gy may be safe to avoid the risk of late radiation myelopathy in a patient with a potentially good prognosis.