Radiation therapy for metastatic brain tumors from lung cancer--a review to devise individualized treatment plans.

We retrospectively analyzed patients with brain metastasis from lung cancer to evaluate treatment modalities for metastatic brain tumors and to devise criteria for individualized treatment plans. Between October, 1986 and December, 1994, 90 patients were selected for this study. The majority (67.8%) received whole-brain radiotherapy (WBRT) alone. WBRT following surgical removal was carried out on 14 patients (15.5%). The median dose of radiation therapy was 43.3 Gy for WBRT. The results were as follows: (1) PS (1 and 2 vs. 3 and 4), which showed a significant difference (p < 0.0001) in survival by both univariate analysis and multivariate analysis, (2) brain metastasis alone or concurrent metastases to other sites (p = 0.0001) by univariate analysis, (3) the primary lesion controlled or uncontrolled (p = 0.0006) by univariate analysis, (4) solitary brain metastasis or multiple brain metastases (p = 0.0145) by univariate analysis. Patients were classified into 3 groups, A (PS1, 2, the primary lesion controlled, no distant metastasis and solitary brain metastasis), B (others except for groups A and C), and C (PS 3,4) based on 4 significant factors. The 1-year survival rates and median survival times were, respectively 75% and 1,767 days in Group A, 40.6% and 313 days in Group B, and 7.8% and 121 days in Group C (p < 0.0001). Although the possibility of individualized treatment was suggested, based on 4 factors associated with the patient's condition and disease progression before treatment for brain metastasis, further evaluation by randomized clinical trials is needed.