Prognostic factors in long-term breast cancer survivors with brain metastases

To the Editor, We read with great interest the article by Lee et al. [1] in which they analyzed retrospectively prognostic factors that affect clinical outcome of breast cancer patients with brain metastases. The overall median survival time was 5.6 months. In their study, 23.1% of patients survive more than 1 year. However, they did not analyze prognostic factors of these long-term survivors, separately. Recent retrospective study evaluated clinical data from 420 patients who had been diagnosed with breast cancer and brain metastasis between 1994 and 2004 at M. D. Anderson Cancer Center. In this study median follow-up after brain metastasis was 6 months (range 0.7–95.9 months) and the overall median survival was 6.8 months [2]. Concerning long-term survivors in this study, 82 patients (19.5%) were alive at least 18 months after diagnosis of CNS metastasis. Of these 82 patients, 25 patients (30%) were HER2 positive. Furthermore, 18 (4.2%) were alive at least 60 months after this diagnosis. The median age of these relatively longer surviving patients was 42 years. Compared to an unselected series of breast cancer patients, this longer surviving population was younger and predominantly premenopausal. Most of these patients had tumors of ductal histologic type, T stage 1 or 2, N stage 0 or 1, and M0 stage at diagnosis. About half of these patients had ER-positive or PR-positive disease, and 73% had grade III disease. Forty-six percent of these patients had a single CNS metastasis. Any or all of these characteristics might explain their potential for prolonged survival.