A scoring system to predict local progression-free survival in patients irradiated with 20 Gy in 5 fractions for malignant spinal cord compression

Dirk Rades, Antonio J. Conde-Moreno, Jon Cacicedo, Theo Veninga, Barbara Segedin, Karmen Stanic, Steven E. Schild
2018 Radiation Oncology  
Local progression-free survival (LPFS = stable or improved motor function/resolution of paraplegia during RT without in-field recurrence following RT) is important when treating metastatic spinal cord compression (MSCC). An instrument to estimate LPFS was created to identify patients appropriately treated with short-course RT instead of longer-course RT plus/minus decompressive surgery. Methods: In 686 patients treated with 20 Gy in 5 fractions alone, ten characteristics were retrospectively
more » ... retrospectively analyzed for LPFS including age, interval between tumor diagnosis and RT of MSCC, visceral metastases, other bone metastases, primary tumor type, gender, time developing motor deficits, pre-RT gait function, number of vertebrae affected by MSCC, and performance score. Characteristics significantly (p < 0.05) associated with LPFS on multivariate analyses were incorporated in the scoring system. Six-month LPFS rates for significant characteristics were divided by 10, and corresponding points were added. Results: On multivariate analyses, visceral metastases (p < 0.001), tumor type (p = 0.009), time developing motor deficits (p < 0.001) and performance score (p = 0.009) were associated with LPFS and used for the scoring system. Scores for patients ranged between 24 and 35 points. Three groups were designed: 24-28 (A), 29-31 (B) and 32-35 (C) points. Six-month LPFS rates were 46, 69 and 92%, 12-month LPFS rates 46, 63 and 83%. Median survival times were 2 months (61% died within 2 months), 4 months and ≥ 11 months (median not reached). Conclusions: Most group A patients appeared sub-optimally treated with 20 Gy in 5 fractions. Patients with survival prognoses ≤2 months may be considered for best supportive care or single-fraction RT, those with prognoses ≥3 months for longer-course RT plus/minus upfront decompressive surgery. Many group B and most group C patients achieved long-time LPFS and appeared sufficiently treated with 20 Gy in 5 fractions. However, based on previous data, long-term survivors may benefit from longer-course RT.
doi:10.1186/s13014-018-1203-y fatcat:vepfc3sxufajrjqecllbfaer64