title: Carcinoma of the breast with medullary-like features: diagnostic challenges and relationship with BRCA1 and EZH2 functions.
abstract: This case presentation reviews the histologic distinction between pure medullary carcinoma and breast carcinomas with medullary-like features. This particular case prompts us to analyze the relationship among medullary carcinoma, basal-like breast carcinomas and carcinomas associated with germline BRCA1 mutations. In addition to now well-defined features, such as expression of high-molecular-weight cytokeratins and EGFR (epidermal growth factor receptor), basal-like tumors have a deficiency or dysfunction of BRCA1. This association in part explains the histologic features of BRCA1-associated breast cancers. Recent studies in our laboratory demonstrate that BRCA1 protein is regulated by a recently described gene, EZH2. These concepts illustrate the important relationships among histopathologic features; genomic profile; single gene abnormalities, such as BRCA1 and EZH2; and growth regulation in this subset of breast carcinomas.
authors.affiliation: Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA. kleer@umich.edu
authors.forename: Celina G
authors.initials: CG
authors.lastname: Kleer
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D002280:Basal Cell Carcinoma / Q000175:diagnosis; D018276:Carcinoma, Medullary / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D003937:Diagnosis, Differential; D000071221:Enhancer of Zeste Homolog 2 Protein; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D018095:Germ-Line Mutation; D006801:Humans; D008875:Middle Aged; D063151:Polycomb Repressive Complex 2; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000235:genetics* / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D014157:Transcription Factors; C498409:EZH2 protein, human; D000071221:Enhancer of Zeste Homolog 2 Protein; D063151:Polycomb Repressive Complex 2; C111164:BRAP protein, human; D044767:Ubiquitin-Protein Ligases