Brain Metastasis Among Female Patients Diagnosed With Stage Iv Breast Cancer

Abstract Among the patients diagnosed with advanced stage of breast cancer there is a possibility of developing distant metastases, brain is one of the predominant sites. The objective of this study is to identify patient characteristics and biomarkers for brain metastasis. From National Cancer Database, 2010 through 2015, we identified 52,753 female patients diagnosed with stage IV breast cancer. Patient demographics, tumor characteristics and biomarkers were analyzed using descriptive statistics. Odds ratios (OR) were computed using logistics regression. Kaplan-Meier estimate was used to compute survival. Of 52,753 female patients diagnosed with stage IV breast cancer, there were 73% non-Hispanic white (NHW), 17% non-Hispanic black (NHB), 6% Hispanic and 4% from ‘other’ race category. The median age of the patients at the time of diagnosis was 62 years. Of the total patients only 8.2% had brain metastatic spread. Brain metastasis was less likely among NHB vs NHW (OR=0.85, p =0.01), among others vs NHW (OR=0.69, p =0.01), with insurance status, government vs no insurance, (OR=0.71, p< 0.01), with private vs no insurance (OR=0.66, p< 0.01), with laterality (left vs bilateral, OR=0.61, p=0.01), (right vs bilateral OR=0.61, p=0.01), ER positive (OR=0.69, p < 0.01), PR positive (OR=0.75, p < 0.01), tumor grade moderately or well differentiated vs poorly or undifferentiated (OR=0.54, p =0.02; OR=0.45, p =0.01) and with 10-year increment in age at the time of diagnosis (OR=0.89, p < 0.001). In this study population five-year survival with and without brain metastasis was 11% and 25% respectively. The protective factors for brain metastatic spread includes NHB or other race category, government or private insurance, cancer either left or right side, moderately or well differentiated tumor, the patients with ER and PR expression. The chance of brain metastatic spread decreases with increasing age. These finding might provide insights for clinicians in treating these patients.