BRCA, Lynch and Other Gene Testing
Although the specific cause of breast cancer is often unknown, certain women (and men) are genetically predisposed to developing it. BRCA designates a set of mutations in genes that control cell growth in breast and other tissues, including the colon and ovary. There are BRCA1 and BRCA2 mutations. A woman with a BRCA gene mutation carries an inherited risk of developing breast, colon and/or ovarian cancer. The risk for such a woman to have breast cancer exceeds 80%.
A woman is more likely to carry a gene mutation if she has:
- A family history of breast and/or ovarian cancer
- Been diagnosed with breast cancer before the age of 45
- Another family member with a BRCA gene mutation
We ask patients entering for their annual exams to fill out a quick family history check list every year, thus permitting Dr Howe to identify those for whom BRCA (or other gene testing) should be performed.
Diagnosis Of BRCA Gene Mutations
A simple saliva test collected in our office is used to test for BRCA mutations. The patient fills a small tube with saliva, which is then sent to a lab for DNA analysis. It takes three to five weeks for results to be available. We then meet to discuss the results.
Women who test positive for BRCA mutations are referred to a medical geneticist, to set up a plan for monitoring and prevention. Women with negative tests may still be at risk for breast cancer, and should be screened on a regular basis.
Preventing Cancer from BRCA Gene Mutations
Women who test positive for a BRCA mutation are advised to take special precautions to help reduce their risk of breast cancer. Theses may include increasing screening frequency, taking medication to kill cancerous cells as soon as they are detected, or preventive surgery. In a prophylactic mastectomy, a surgeon removes healthy breast tissue. This may reduce a patient’s risk of developing breast cancer by as much as 90 percent.
Breast cancer in men is extremely rare. Men who have mutations in BRCA genes, however, have a dramatically increased risk of getting the disease. Approximately 50 percent of men who develop breast cancer have BRCA gene mutations.
Because the BRCA genes also associate with ovarian and colon cancer, we advise that patients with BRCA mutations have increased screening for ovarian and colon cancer as well as for breast cancer.
Other Genetic Syndromes
While BRCA mutations are the best known of the genetic cancer syndromes, there are others, including Lynch syndrome, Multiple Endocrine Neoplasia syndromes and Peutz-Jeghers syndrome. Our screening process for BRCA mutations will detect these syndromes also.