Clinical features and outcome of brain metastasis in breast cancer patients (Saudi Arabia).

Abstract

e11516 Background: Brain metastasis may occur in 10-15% of patients with breast cancer (BC). Such a diagnosis is associated with poor survival. In Saudi Arabia, there is no data on brain metastasis in BC patients. Our aim is to analyze the clinical characteristics, survival of different subtypes of BC patients with brain metastasis and to identify possible prognostic factors. Methods: Patients with brain metastasis were identified from a data base of BC cases diagnosed from January 2002 to July 2009 at King Abdulaziz Medical City, Saudi Arabia. Their clinical characteristics, pathological features and prognostic factors were analyzed. Survival since diagnosis of brain metastasis was calculated using Kaplan-Meier estimate. A proportional hazards regression model was conducted to evaluate the effect of different subtypes. Results: Out of total 594 BC patients, 34 (5.72%) with brain metastasis were identified based on imaging and clinical findings. Median age at primary BC diagnosis was 39 years (range, 26 to 69) and median time to CNS metastasis was 16.01 months (range 0.03 to 47.7), 29 (85.29%) were ductal carcinoma, 3 (8.82%) lobular and 2 (5.88%) were unknown. HER2 overexpression was found in tumor from 16 patients, 6 (17.65%) of them were triple positive, 9 (26.47%) lacked expression of ER and PR and 1 (2.94%) had estrogen ER over expression with no progesterone PR overexpression. Of the 15 that lacked HER 2 overexpression, 7 (20.59%) overexpressed ER/PR, 2 (5.88%) overexpressed ER alone and 6 (17.65%) were triple negative (TNBC), while the remainder were unknown. Regarding CNS involvement, 25 (73.53%) were intraparenchymal while 3 (8.82%) had leptomeningeal involvement and 6 (17.65%) had both. Conclusions: Nearly half of the BC patients with brain metastasis express HER2 TNBC confers the worst outcome among all histological subtypes. Multiple Cox proportional hazards regression analysis for overall survival (n=34). Variable Hazard ratio 95% confidence interval P value Receptor status (vs. triple negative) ER-/PR-/HER2 + 0.151 0.042-0.541 0.0037 ER+ or PR+/HER2 - 0.132 0.023-0.753 0.0227 ER+/PR+/HER2 - 0.262 0.078-0.880 0.0302 Triple positive 0.128 0.030-0.543 0.0053