Risk factors of brain metastasis in a series of Egyptian breast cancer patients: A single-institution experience.

Abstract

50 Background: Incidence of cerebral metastasis is increasing among breast cancer patients. Many factors have been reported associated with increased risk of brain metastasis. The aim of this retrospective analysis is to investigate the predictive factors for the development of brain metastasis in breast cancer patients. Methods: We retrospectively analyzed histologically proven breast cancer patients who presented to Cairo Oncology Center (COC) in the period from 1999 till 2008, with follow up period of 6 months at least for those in adjuvant setting. The following factors were analyzed: age, tumor size and grade, nodal status, ER, PgR and HER2 over-expression status. Results: Our study included 2,338 patients. 96 patients (4.1%) experienced brain metastasis during the course of their disease. 3 patients had brain metastasis among other sites of distant spread at first presentation to COC. 30 out of 96 patients (31.25%) with localized breast cancer had brain metastasis at first relapse with 13 (13.5%) of them had isolated brain metastasis. In a median follow-up of 37.1 months (6-277) the median time to develop brain metastasis was 26.5 months (0-144). Based on univariate analysis, the following variables were associated with shorter time to develop brain metastasis: tumor size more than 5 cm (HR = 2.1, 95% CI 1.14-3.87), lymph node involvement at diagnosis (HR = 1.57, 95%CI 1.17-2.10), ER negativity (HR = 1.58, 95%CI 1.33-1.73), PgR negativity (HR = 1.55, 95%CI 1.29-1.72) and HER2-neu over-expression (HR = 2.68, 95%CI 1.51-4.75). On multivariate analysis, only patients with lymph node involvement at diagnosis and those with HER2-neu positive breast cancer were associated with shorter time to develop brain metastasis. Conclusions: We concluded that HER2 over-expression as well as lymph node involvement are the 2 main factors associated with shorter time to develop brain metastasis. These patients could be good candidates for trials investigating the role of any prophylactic intervention to decrease their risk to develop brain metastases.