Final Results of a Prospective Study Comparing the Local Control of Short-course and Long-course Radiotherapy for Metastatic Spinal Cord Compression

Purpose: Many patients with metastatic spinal cord compression (MSCC) live long enough to develop a recurrence in the irradiated spinal area. This is the first prospective study that has compared local control of different radiotherapy schedules for MSCC.

Methods And Materials: A total of 265 patients treated with radiotherapy alone were included in this prospective nonrandomized study. The primary goal was to compare local control from short-course (1 × 8 Gy/5 × 4 Gy, n = 131) and long-course radiotherapy (10 × 3 Gy/15 × 2.5 Gy/20 × 2 Gy, n = 134). Secondary end points were motor function and survival. The analysis of local control (no MSCC recurrence in the irradiated spinal area) included the 224 patients with improvement or no change of motor deficits during radiotherapy. Eleven additional factors were evaluated for outcomes.

Results: One-year local control was 61% after short-course and 81% after long-course radiotherapy (p = 0.005). On multivariate analysis (MVA), improved local control was associated with long-course radiotherapy (p = 0.018). Motor function improved in 37% after short-course and 39% after long-course radiotherapy (p = 0.95). Improved motor function was associated with better performance status (p = 0.015), favorable tumor type (p = 0.034), and slower development of motor deficits (p < 0.001). One-year survival rates were 23% after short-course and 30% after long-course radiotherapy (p = 0.28). On MVA, improved survival was associated with better performance status (p < 0.001), no visceral metastases (p < 0.001), involvement of only one to three vertebrae (p = 0.040), ambulatory status (p = 0.038), and bisphosphonate administration after radiotherapy (p < 0.001).

Conclusions: Long-course radiotherapy was associated with better local control, similar functional outcome, and similar survival compared to short-course radiotherapy. Patients with a relatively favorable expected survival should receive long-course radiotherapy.