الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
”Breast cancer is the most commonly diagnosed malignancy in women. Although female BC is a leading cause of cancer mortality worldwide, it is often diagnosed at an early stage when it is potentially curable (Brentnall et al., 2018). BC is biologically heterogeneous, with different subtypes exhibiting different prognoses. Gene expression profiling has identified five molecular subtypes with distinct behaviors and clinical outcomes: luminal A, luminal B, HER2 enriched, basal-like, and normal-like tumors. Basal-like tumors are predominately represented by the triple negative phenotype, characterized by the lack of estrogen receptor (ER), progesterone receptor (PR), and HER2/neu oncogene (Perou et al., 2000). Triple negative breast cancers (TNBC) account for 15–20% of all BC cases, are associated with a higher propensity for early recurrences, and have a worse 5-year OS compared with other BC subtypes. In a study from the National Cancer Database (NCDB), TNBC patients had distinct demographic and racial/ethnic features as compared to non-TNBC patients (Plasilova et al., 2016). TNBC is a more aggressive phenotype, including larger tumor size, higher tumor grade, but less likelihood of nodal involvement (Dent et al., 2007).Although targeted therapies have improved management of ER-positive and HER2-positive BC, cytotoxic chemotherapy remains the mainstay of systemic therapy for TNBC patients. Despite worse prognosis, TNBC has higher response rates to chemotherapy. Outcomes following neoadjuvant and adjuvant chemotherapy are comparable for BC patients in general (Asselain et al., 2018).
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