Approximately 10% of the 1,92,000 women who have breast cancer have hereditary form of the disease.
BRCA1 and BRCA2 are protective genes that help in ensuring that the cells do not turn malignant ( called tumor suppressor genes) and are found in every one. A mutation or alteration in these genes increases the risk of developing breast cancer especially in families with multiple cases of breast and ovarian cancer. A woman with any of these mutations could develop the cancer rather young in life.
However it is not mandatory that a woman who belongs to a high risk family would carry the mutated genes neither is it mandatory for a woman who carries these BRCA mutations to actually develop the cancer.
Men too, with BRCA mutations, are a greater risk of developing breast cancer.
BRCA mutations are detected by analyzing the DNA through special studies (called Polymerase Chain Reaction or PCR) .
A person who tests positive for any BRCA mutation has to be continually monitored through physical breast exam and mammograms. To minimize their risks of developing cancer they should also avoid additional triggering factors such as alcohol or drugs and also adopt a healthy lifestyle.
Some people who have tested positive chose to have preventive surgeries such as prophylactic mastectomy or removal of their ovaries (salpingo-oophorectomy). For some individuals preventive chemotherapy is the method of choice.
Approximately two thirds of breast cancers in post menopausal women are –
- Estrogen receptor positive (ER+)
- Progesterone receptor positive (PR+)
In normal cells, HER2 is a cell-surface protein involved in cell growth and division. In cancer cells this protein gets activated resulting in tumor formation. In about 20-30% of individuals with breast cancer, HER2 is overexpressed.
It is recommended that all breast cancers are screened for estrogen and progesterone receptors and HER2.
