Background and purpose: This study aimed to develop and validate a scoring system to predict the survival of patients receiving whole-brain radiotherapy (WBRT) alone for brain metastases from less radiosensitive tumors.
Patients and methods: The study included data from 176 patients with brain metastasis from renal cell carcinoma, malignant melanoma or colorectal cancer. Patients were divided into a test group (N=88) and a validation group (N=88). In the multivariate analysis of the test group, age, Karnofsky Performance Status and extracranial metastasis were significantly associated with survival. These three factors were included in the scoring system. The score for each factor was determined by dividing the 6-month survival rate (in %) by 10. The total score represented the sum of the three scores. According to the total scores-which ranged from 5 to 14 points-three prognostic groups were created.
Results: The 6-month survival rates in the test group were 11% for 5-8 points (N=47, group A), 38% for 9-11 points (N=29, group B) and 83% for 12-14 points (N=12, group C). In the validation group the 6-month survival rates were 12, 31 and 75%, respectively. Comparisons between the prognostic groups A, B and C of the test group with those of the validation group did not reveal any significant differences.
Conclusion: The new scoring system based on three independent prognostic factors can help to estimate the survival of patients with brain metastases from a less radiosensitive tumor. The score appears to be valid and reproducible.