title: Basal breast cancer: a complex and deadly molecular subtype.
abstract: During the last decade, gene expression profiling of breast cancer has revealed the existence of five molecular subtypes and allowed the establishment of a new classification. The basal subtype, which represents 15-25% of cases, is characterized by an expression profile similar to that of myoepithelial normal mammary cells. Basal tumors are frequently assimilated to triple-negative (TN) breast cancers. They display epidemiological and clinico-pathological features distinct from other subtypes. Their pattern of relapse is characterized by frequent and early relapses and visceral locations. Despite a relative sensitivity to chemotherapy, the prognosis is poor. Recent characterization of their molecular features, such as the dysfunction of the BRCA1 pathway or the frequent expression of EGFR, provides opportunities for optimizing the systemic treatment. Several clinical trials dedicated to basal or TN tumors are testing cytotoxic agents and/or molecularly targeted therapies. This review summarizes the current state of knowledge of this aggressive and hard-to-treat subtype of breast cancer.
authors.affiliation: Département d'Oncologie Médicale, Institut Paoli-Calmettes, Centre de Recherche en Cancérologie de Marseille, UMR891 Inserm, Marseille, France. bertuccif@marseille.fnclcc.fr
authors.forename: F
authors.initials: F
authors.lastname: Bertucci
authors.forename: P
authors.initials: P
authors.lastname: Finetti
authors.forename: D
authors.initials: D
authors.lastname: Birnbaum
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D019313:BRCA1 Protein / Q000235:genetics; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D001943:Breast Neoplasms / Q000188:drug therapy / Q000453:epidemiology / Q000378:metabolism* / Q000473:pathology; D002986:Clinical Trials as Topic; D005260:Female; D006801:Humans; D009154:Mutation; D009361:Neoplasm Invasiveness; D018295:Neoplasms, Basal Cell / Q000188:drug therapy / Q000453:epidemiology / Q000378:metabolism* / Q000473:pathology; D011379:Prognosis
chemical_list: D000970:Antineoplastic Agents; D019313:BRCA1 Protein; C492913:BRCA1 protein, human; D014408:Biomarkers, Tumor
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