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Genetic testing

High risk options: things you should know about breast cancer risk and genetic testing

Breast and ovarian cancer are topics of concern for all women, regardless of their family history. The National Cancer Institute reports that close to 200,000 cases of breast cancer and 25,000 cases of ovarian cancer are diagnosed annually in the United States. While the majority of breast and ovarian cancers are not caused by inherited risk factors, research has shown that about 10 percent of these cases are hereditary and linked to the breast cancer gene (BRCA 1 or BRCA 2 mutation).

Do most women who develop breast cancer have a family history?

No. The vast majority of breast cancers will occur in women who have NO family history of breast cancer and are not linked to heredity or genetics. These nonhereditary cancers are called Sporadic Breast Cancers and are the most common type of breast cancer. The risk of breast cancer increases as a woman ages. It is less likely to occur before age 50. If you live to 90 then your risk of developing breast cancer is 1 in 8 or about 13 percent even with no family history. Therefore, ALL women over age 40 should be screened for breast cancer with mammograms, even if they have no family history.

Does that mean that women with a family history have a lifetime risk that may be greater than 1 in 8?

Yes. Women with a strong family history of breast cancer may have an elevated risk compared to women with no family history. Their risk, therefore, may be higher than the 1 in 8 lifetime risk described above. The actual risk depends on the number of family members with breast or ovarian cancer and the ages in which those family members were diagnosed. Determination of the risk may be done with computerized models such as the Gail Model. The family and personal history is placed into this computer model and a 5-year risk and a lifetime risk of developing breast cancer can be calculated. Risk depends on age, family history and several other factors including the age of first menstrual cycle and pregnancy, previous breast biopsies, and race. Breast cancers that develop in women with strong family histories are known as Familial Breast Cancer.

In some families, physicians get very concerned that their patient may have an even higher risk of breast cancer than expected due to an alteration or mutation in their genes. The lifetime risk of developing breast cancer in a patient with these altered genes could be as high as 85 percent. Cancers that develop in women with an alteration or mutation in their genes are called Hereditary Breast Cancer.

What are genes and what is the BRCA (breast cancer) gene?

We're all born with two copies of about 30,000 different genes. One copy of each gene comes from our mother and the other from our father. Two genes in particular, BRCA 1 and BRCA 2 normally work to prevent breast and ovarian cancer. But, in some cases we can inherit a BRCA 1 or BRCA 2 alteration or mutation from EITHER parent. This alteration interferes with normal gene activity and makes the person with the altered gene more susceptible to developing breast or ovarian cancer.

How many people have the altered or mutated breast cancer gene?

These genes are fairly uncommon. It is estimated that about 10% of women who are diagnosed with breast cancer will have one of these altered genes. Remember. Men can also have the altered gene. Men with the gene do have an increased risk of developing breast cancer compared to men without the gene. Men can also pass the gene on to their sons or daughters. Their daughters then have a very high risk of developing breast cancer.

How do I know if I am at risk for this gene?

There are several risk factors that clinicians look for. The most important factor is a blood relative who has tested positive for the gene. Other risk factors include a history in yourself or a family member of breast cancer before age 50; ovarian cancer at any age; male breast cancer; both breast and ovarian cancer; breast cancer in both breasts, multiple close family members with breast cancer; or Askenazi or Eastern European Jewish descent. Close family members are defined as mother, father, brother, sister, grandparent (either mother or father's side), mother's sister or brother, or father's sister or brother.

If I have those risk factors, can I be tested to see if I have the gene alteration in BRCA 1 or BRCA 2?

Yes. Although the lab test itself is quite complex, only a blood sample is needed from anyone considering the test. The blood sample is sent to Myriad Genetic Laboratories for analysis. The analysis is a complex process called gene sequencing which looks for altered genes and may take several weeks to complete.

How much does it cost and will my Insurance pay for the BRCA testing?

Most health insurance plans pay for the test for those patients with appropriate risk factors. The full panel of testing costs $3,150 and the limited panel (when one member of the family has already tested positive) costs $350.

What is my risk of developing cancer if I have the gene?

Those who test positive for the gene have a very high lifetime risk of developing breast and ovarian cancer. The risk of developing breast cancer by age 50 with the gene is as high as 50 percent. By age 70, that risk jumps up to as high as 87 percent. The risk of ovarian cancer is as high as 44 percent compared to <2 percent in the general non-affected population. Women who have tested positive for the BRCA 1 or BRCA 2 gene may not necessarily develop cancer, since genes are not the only factor that affects cancer risk.

If I have been treated for breast or ovarian cancer in the past, is there any reason to test?

Yes: People with a BRCA gene mutation who have already had cancer are at a greater risk of developing a new cancer, either in the ovaries or the breast. Knowing your BRCA status can help you take steps to reduce this risk or detect another potential cancer at an early more treatable stage. The results may also be helpful for your family members. If the gene is present that means that your parents, siblings and children (including brothers and sons) have a 50:50 chance of also having the mutated gene.

If I don't have cancer, and test positive for the gene, what are my options?

It is typically recommended that a more aggressive screening program for breast and ovarian cancer begin at a much earlier age (around 25) so that cancers can be caught at an early more treatable stage. You may also consider a medication such as tamoxifen to lower the risk of breast cancer by as much as 50 percent. Lifestyle modifications such as a good diet and exercise have also been shown to reduce risk slightly. Finally, some women chose to have surgery to prevent cancer by taking an aggressive step and having their breasts and/or ovaries removed.

Is Genetic Discrimination prohibited by law?

Yes: A number of federal and state laws prohibit insurance discrimination to various degrees. A new federal mandate was just signed into law called the Genetic Information Nondiscrimination Act (GINA) which protects patients against employment and insurance discrimination. A number of other laws also protect your privacy including the Health Insurance Portability Protection Act (HIPPA). Genetic test results are strictly confidential. Your insurer and your employer will not have access to the results.

Is BRCA Testing Appropriate For Men as Well?

Yes: If a man has a personal history of breast cancer or a significant family history of breast or ovarian cancer, he may have a BRCA 1 or BRCA 2 mutation. Men in these circumstances should consider testing. Although male breast cancer is rare, men who carry BRCA mutations are more likely to develop breast cancer as well as prostate cancer. Men with BRCA mutations also have a 50 percent chance of passing these mutations on to their children, whether or not they've been diagnosed with cancer.