Is Short-Course Radiotherapy with High Doses per Fraction the Appropriate Regimen for Metastatic Spinal Cord Compression in Colorectal Cancer Patients?

Abstract

Various radiotherapy (RT) schedules are used worldwide for metastatic spinal cord compression (MSCC). Every treatment session may cause discomfort to the mostly debilitated patients. A short overall treatment time appears beneficial, especially for MSCC patients with an extremely poor survival such as colorectal cancer patients. This study evaluates whether short-course RT (1 x 8 Gy given in 1 day, 5 x 4 Gy given in 1 week) is as effective as long-course RT (10 x 3 Gy given in 2 weeks, 15 x 2.5 Gy given in 3 weeks, 20 x 2 Gy given in 4 weeks) and whether higher doses per fraction (more cell kill) and shorter overall treatment time (less repopulation) can compensate for lower total doses. 81 colorectal cancer patients with MSCC were retrospectively investigated. The following potential prognostic factors for functional outcome were analyzed: age, sex, performance status, number of involved vertebrae, ambulatory status before RT, time of developing motor deficits before RT, radiation regimen (short-course, n = 31, vs. long-course RT, n = 50). Improvement of motor function occurred in 14% of the patients, no change in 68%, and deterioration in 19%. There were no significant differences between short-course and long-course RT regarding improvement or deterioration of motor function (p = 0.50). Time of developing motor deficits before RT was the only significant prognostic parameter for functional outcome (> 7 days better than 1-7 days; p < 0.001). No significant difference was observed between short-course and long-course RT with respect to functional outcome. In the clinical situation, short-course RT may be considered preferable, as it means less patient discomfort.