A new scoring system to predicting the survival of patients treated with whole-brain radiotherapy for brain metastases

Purpose: To create a scoring system to estimate survival of patients who received whole-brain radiotherapy (WBRT) for brain metastases. Material and Methods: Based on a multivariate analysis of 1,085 retrospectively analyzed patients, a scoring system was developed. This score was based on the four significant prognostic factors found in the multivariate analysis including: age, performance status, extracranial metastases at the time of WBRT, and interval between tumor diagnosis and WBRT. The score for each prognostic factor was determined by dividing the 6-month survival rate (in %) by 10. The total score represented the sum of the partial scores for each prognostic factor. Total scores ranged from 9 to 18 points, and patients were divided into four groups. For each group, survival was compared for short-course (5 × 4 Gy) versus longer-course WBRT (10 × 3 Gy/20 × 2 Gy). Results: Actuarial 6-month survival rates were 6% for patients with scores of 9-10 points, 15% for those with scores of 11-13 points, 43% for those with scores of 14-16 points, and 76% for those with scores of 17-18 points (p < 0.001). Longer-course WBRT was not associated with better survival than short-course WBRT in any of the four groups. Conclusion: Patients with brain metastases receiving WBRT can be grouped with this score to estimate survival. Short-course and longer-course WBRT resulted in similar survival in all groups studied. However, in the more favorable patients with scores of 17-18, longer-course WBRT with lower doses per fraction should be considered, as these schedules have been associated with less neurocognitive toxicity.