Breast Pathology and Cancer Diagnosis

Breast Cancer and Genetics

The two most common genetic risk factors for breast cancer are the BRCA1 & BRCA2 genes. Approximately 5% of all breast cancers are caused by a recognised specific genetic predisposition due to germ line mutations of one of two different genes: BRCA1 located on Chromosome 17q, BRCA2 located on Chromosome 13q. BRCA1 mutations also predispose to carcinoma of the ovary and possibly carcinoma of the Fallopian tube. The risk of developing breast cancer among carriers is around 55% by age 70. BRCA2: The product of BRCA2 is involved in controlling gene function and DNA repair. Gene function involves in transcriptional activation and completion of cell division by cytokinesis.  Majority of BRCA2-associated tumours are invasive ductal, no special-type tumours.