Brain Metastasis in Breast Cancer Patients

A retrospective cohort study will be conducted in the Henry Ford Health System (HFHS). Using medical record review, we will identify all women diagnosed with advanced stage (stage III and IV) breast cancer between January 1, 1995- December 31, 2007. For each case included in the study, we will obtain data on demographics, tumor information, treatment related medical encounters and procedures, and occurrence and timing of brain and/or other distant metastases. The main outcome for this study is the development of distant metastases. Each patient in the cohort will be classified as to the occurrence and date of distant metastases. Metastases will be classified as Brain, Distant lymph node, Lung/pleural effusion, Liver, Bone, Other visceral, Other non-visceral. Other secondary outcomes to be explored include: * Survival after advanced breast cancer-time in months from the date of advanced stage breast cancer diagnosis until death or end of study period * Time to brain metastases-time in month from the date of advanced stage breast cancer diagnosis until brain metastases diagnosis * Survival after brain metastases-time in months from the date of diagnosis of brain metastases until death or end of study period