Sporadic Invasive Breast Carcinomas With Medullary Features Display a Basal-like Phenotype
- 1 April 2007
- journal article
- research article
- Published by Ovid Technologies (Wolters Kluwer Health) in The American Journal of Surgical Pathology
- Vol. 31 (4), 501-508
- https://doi.org/10.1097/01.pas.0000213427.84245.92
Abstract
It is not clear whether invasive breast carcinomas with medullary features (IBCMFs, atypical medullary carcinomas) constitute a specific phenotype of breast cancer that is of biologic significance. Because medullary features are common in BRCA1-associated carcinomas and these tumors frequently show a basal-like phenotype, we examined whether IBCMFs expressed basal/myoepithelial markers and had a basal-like phenotype. We studied the immunohistochemical expression of 15 markers in tissue microarrays containing samples from 35 IBCMFs and 39 grade 3 invasive ductal carcinomas (IDCG3s) of no special type. In addition, we analyzed EGFR, C-MYC, and CCNE gene amplification by fluorescence in situ hybridization, because the expression of these genes is known to be associated with the basal-like phenotype. We defined the basal-like phenotype according to the criteria of Nielsen et al as being those tumors that were ER/HER2-negative and cytokeratin (CK) 5/6- and/or epidermal growth factor receptor-positive. IBCMFs were more frequently hormone receptor- and HER2-negative, but had greater expression of proliferation markers and p53. In addition, IBCMFs more frequently expressed basal/myoepithelial markers, such as CK5/6 and P-cadherin. A basal-like phenotype was found in 62.9% of IBCMFs but in only 18.9% of IDCG3s. No differences in gene amplification were found between IBCMFs and IDCG3s, although C-MYC amplification was more common in tumors without a basal-like phenotype. The identification of IBCMF as an independent group of tumors could be of clinical significance, given the high incidence of cases with a basal-like phenotype, which is a group of tumors with different prognosis and chemotherapy response from those of IDCG3s of no special type.This publication has 53 references indexed in Scilit:
- Spectrum of breast cancer metastasis in BRCA1 mutation carriers: highly increased incidence of brain metastasesAnnals of Oncology, 2005
- Cyclin E Overexpression Obstructs Infiltrative Behavior in Breast Cancer: A Novel Role Reflected in the Growth Pattern of Medullary Breast CancersCancer Research, 2005
- EGFR gene amplification in breast cancer: correlation with epidermal growth factor receptor mRNA and protein expression and HER-2 status and absence of EGFR-activating mutationsLaboratory Investigation, 2005
- HER-2/neu and Topoisomerase IIα Gene Amplification and Protein Expression in Invasive Breast CarcinomasAmerican Journal of Clinical Pathology, 2005
- Placental Cadherin and the Basal Epithelial Phenotype of BRCA1-Related Breast CancerClinical Cancer Research, 2005
- Prognostic Relevance of Gene Amplifications and Coamplifications in Breast CancerCancer Research, 2004
- Prognostic value of morphology and hormone receptor status in breast cancer – a population-based studyBritish Journal of Cancer, 2004
- Expression of luminal and basal cytokeratins in human breast carcinomaThe Journal of Pathology, 2004
- Pattern of Amplification and Overexpression of the Eukaryotic Initiation Factor 4E Gene in Solid TumorJournal of Surgical Research, 1999
- The histologic phenotypes of breast carcinoma occurring before age 40 years in women with and without BRCA1 or BRCA2 germline mutationsCancer, 1998