Survival in patients with brain metastases from breast cancer: The importance of HER-2 status

BACKGROUND. Brain metastases (BM) are the most common intracranial tumors in adults. To the authors' knowledge, established prognostic factors for survival after the diagnosis of BM in breast cancer patients do not take into account HER-2 status, which may have increasing relevance in the trastuzumab therapy era. METHODS. The authors identified 83 patients with breast cancer and new parenchymal BM diagnosed between January 1, 2001 and December 31, 2005 who were treated at Massachusetts General Hospital. Survival was estimated using the Kaplan-Meier method and curves were compared using the log-rank test. A Cox proportional hazards model was used to determine independent predictors of survival. RESULTS. The median overall survival from the time of BM was 8.3 months. On univariate analysis, HER-2-positive patients were found to have prolonged survival after BM compared with HER-2-negative patients (17.1 months vs 5.2 months). Patients with triple negative disease had a median survival of 4.0 months, compared with 11.2 months for all other patients. Additional predictors of improved survival on univariate analysis included ≤3 BM, controlled or absent systemic disease, and controlled local disease. On multivariate analysis, only HER-2 status, number of BM, and local disease status remained independent predictors of survival. CONCLUSIONS. HER-2 status is a strong predictor of survival after the diagnosis of BM. The survival of breast cancer patients with BM appears to be improving, but a better understanding of both the predictors of brain recurrence and the delayed effects of treatment is needed to properly counsel patients regarding the riskbenefit ratio of various treatment modalities.