Background: To create a validated scoring system predicting survival of breast cancer patients with metastatic spinal cord compression (MSCC).
Patients and methods: Of 510 patients, one half were assigned to either the test or the validation group. In the test group, eight pretreatment factors (age, performance status, number of involved vertebrae, ambulatory status, other bone metastases, visceral metastases, interval from cancer diagnosis to radiotherapy of MSCC, time of developing motor deficits) plus the radiation regimen were retrospectively investigated. Factors significantly associated with survival in the multivariate analysis were included in the scoring system. The score for each factor was determined by dividing the 6-month survival rate (%) by ten. The total score was the sum of the scores for each factor.
Results: In the multivariate analysis of the test group, performance status, ambulatory status, other bone metastases, visceral metastases, interval from cancer diagnosis to radiotherapy of MSCC, and time of developing motor deficits were significant for survival and included in the score. Total scores ranged from 30 to 50 points. In the test group, the 6-month survival rates were 12% for 30-35 points, 41% for 36-40 points, 74% for 41-45 points, and 98% for 46-50 points (p < 0.0001). In the validation group, the 6-month survival rates were 14%, 46%, 77%, and 99%, respectively (p < 0.0001).
Conclusion: The survival rates of the validation group were similar to the test group. Therefore, this score was reproducible and can help when selecting the appropriate radiotherapy regimen for each patient taking into account her survival prognosis.