Reducing the overall treatment time for radiotherapy of metastatic spinal cord compression (MSCC): 3-year results of a prospective observational multi-center study

Background: This prospective multi-center study investigates a reduction of the overall treatment time for radiotherapy of MSCC, which is important for these mostly disabled patients. Patients and methods: Two standard fractionation schedules, 30 Gy/10 fractions/2 weeks (n = 71) and 40 Gy/20 fractions/4 weeks (n = 65) were compared for functional outcome and ambulatory status. Motor function was graded using an 8-point-scale before RT, at the end and at 6, 12 and 24 weeks after RT. A multi-variate analysis was performed for functional outcome. Included variables were the fractionation schedule and the three relevant prognostic factors. These factors are the type of primary tumor, the time of developing motor deficits before RT and the pre-treatment ambulatory status. Results: The ambulatory rates were 49% in the 30 Gy group and 52% in the 40 Gy group before RT (P = 0.888), and 56% and 60% after RT (P = 0.888). Improvement of motor function occurred in 45% of the 30 Gy group and 40% of the 40 Gy group (P = 0.752). The relevant prognostic factors were comparably distributed in both groups. According to the multivariate analysis, a slower development of motor deficits (P < 0.001), a favorable histology (P = 0.040) and being ambulatory (P = 0.045) were associated with better functional outcome, whereas the fractionation schedule had no significant impact (P = 0.311). Conclusions: The data suggest both schedules to be comparably effective for functional outcome. Thus, 30 Gy/10 fractions/2 weeks should be applied instead of 40 Gy/20 fractions/4 weeks. The reduction of the overall treatment time from 4 to 2 weeks means less discomfort for the paraparetic or paraplegic patient.