Related Experiment Video
Updated: Jul 14, 2026

Identifying the Effects of BRCA1 Mutations on Homologous Recombination using Cells that Express Endogenous Wild-type BRCA1
Published on: February 17, 2011
BRCA1 germline mutation in a woman with metaplastic squamous cell breast cancer
Annette Breuer1, Michaela Kandel, Annette Fisseler-Eckhoff
1Klinik für Gynäkologie und gynäkologische Onkologie, Dr. Horst Schmidt Klinik, Wiesbaden, Germany. gynecology@web.de
Background:
Breast cancers arising in women with germline BRCA1 mutations are most likely to be estrogen receptor (ER), progesterone receptor (PR), and HER2/neu negative (so-called triple negative or basal-like breast cancers). Metaplastic carcinoma with pure squamous differentiation is a very rare histological subtype (0.1% of all breast cancers) and is usually ER, PR, and HER2/neu negative by immunohistochemistry. A BRCA1 germline mutation in squamous cell breast cancer has never been reported.
Case Report:
A 25-year-old woman was diagnosed with squamous cell cancer of the breast. Three years later, she developed contralateral breast cancer, also of the squamous cell subtype. Both tumors were triple negative. Because of the patient's history and her strong family history, genetic testing was recommended. The patient was found to be carrier of a BRCA1 germline mutation.
Conclusion:
We report, to our knowledge, the first case of a BRCA1 mutation in a woman with metaplastic squamous cell breast cancer.
More Related Videos
13:04In Vivo and Ex Vivo Approaches to Study Ovarian Cancer Metastatic Colonization of Milky Spot Structures in Peritoneal Adipose
Published on: October 14, 2015
08:15gDNA Enrichment by a Transposase-based Technology for NGS Analysis of the Whole Sequence of BRCA1, BRCA2, and 9 Genes Involved in DNA Damage Repair
Published on: October 6, 2014
Related Concept Videos
The Retinoblastoma Gene
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
Cancers Originate from Somatic Mutations in a Single Cell