ATYPICAL RESPONDERS LANDSCAPE REVIEW ∙ OCTOBER, 2017 38 De-identified data: information about a patient’s medical condition that is anonymous due to removal of personal information such as name, social security number, date of birth, etc. De- identification allows data from an individual patient to be shared among researchers for analysis without compromising the patient’s privacy. De novo MBC: breast cancer that is diagnosed as metastatic at the first cancer diagnosis. These patients were not diagnosed with early stage disease, but were considered metastatic at the initial cancer diagnosis. Downregulated: decreased Extracellular matrix: proteins located outside of cells that provide physical support to cells Ex vivo: tissue or cells removed from a person or animal Genotype: the genes carried by an individual that determine the characteristics of proteins, cells, organs, or the entire individual Germline-derived polymorphism: DNA changes that are inheritable (found in egg and sperm cells and thus passed down to offspring). The variants may or may not influence cancer etiology, progression, or metastasis, and are more likely to influence a response to therapy. Hazard ratio: compares the likelihood of an event (such as death) occurring in one population compared to another population (for example, a treated group and a placebo group) over time and is generally shown as a number close to 1.0. A hazard ratio higher than 1.0 means an increased likelihood of an event occurring. For example, a hazard ratio of 2.0 means that the event is twice as likely to occur in one population compared to another population. A hazard ratio less than 1.0 means the event is less likely to occur in one population compared to the other, and a hazard ratio of 1.0 means that the event is equally likely to occur in the two populations. Heterogeneous: different or mixed. A heterogeneous population of patients has many different characteristics. A heterogeneous tumor has cells with different properties. In vitro: in a test tube or culture plate In vivo: in a person’s or animal’s body Intraperitoneal: within or through the membrane that lines the walls of the abdominal cavity Kinase: A kinase is a type of protein in the body that helps control cell division. Certain drugs such as Ibrance™ (palbociclib), Kisqali™ (ribociclib), and VerzenioTM (abemaciclib) inhibit the cyclin-dependent kinase 4 and 6 (CDK 4/6). Meta-analysis: a systematic process in which similar data collected from multiple studies are re- analyzed to increase statistical power