A growing number of Spokane-area women who are at high risk for inherited breast or ovarian cancer are turning to their genes for answers, in the hope that what they find might save a life - their own or a family member's.
Breast cancer is the most common cancer in women, striking one in eight women in the U.S., says Dr. Joni Nichols, of Spokane-based Cancer Care Northwest. While ovarian cancer is more rare - striking one in 67 women - it's called a "silent killer" because it often goes undetected until reaching an advanced stage, Nichols says.
Between 5 percent and 10 percent of women who have been diagnosed with breast cancer have a strong family history of cancer that would indicate they may have a genetic predisposition to the disease - and their family members might, too, says Lael Hinds, a genetic counselor at Spokane-based Inland Northwest Genetics Clinic. Hereditary cancer is caused by an inherited genetic change that leads to increased susceptibility for certain types of cancer, she says.
The two most common inherited gene mutations that can lead to higher risks for breast and ovarian cancer - found in the BRCA1 and BRCA2 genes - can raise a woman's risk of developing breast cancer at some point during her lifetime to as high as 84 percent, and her risk of developing ovarian cancer to as-high as 40 percent, Hinds says. BRCA1 and BRCA2 genes help control normal cell growth, so when something goes wrong in them, cells can grow out of control, which creates a tumor, she says.
Myriad Genetic Laboratories Inc., of Salt Lake City, launched the BRCA tests commercially in 1996 and is the only lab in the U.S. that offers them, she says.
"When I came here in 1995, we saw a handful of families for inherited-cancer counseling," Hinds says. "Now, it's not uncommon to have a couple of families on our schedule each week."
Nichols says demand at Cancer Care Northwest for genetic testing among patients who already know they have breast or ovarian cancer has risen particularly in the past two years. She attributes the increase partly to more widespread acceptance of the testing among such patients and to more referrals by primary-care doctors for high-risk patients to oncologists and genetic counselors.
"Many of the patients I see have already been diagnosed with cancer, so they're just trying to make good decisions about their own care, and wondering how they can help their family members," Nichols says.
Other types of hereditary cancer in addition to breast and ovarian cancer include colon cancer, pancreatic cancer, and melanoma, Hinds says. While BRCA1 and BRCA2 gene mutations are the main gene mutations responsible for hereditary breast and ovarian cancer, other less-common genetic mutations also can be involved in those cancers, as can genetic mutations that haven't been discovered yet, Hinds says. Both males and females with a BRCA mutation have a 50 percent chance of passing the mutation on to each of their children, she says.
Prime candidates for genetic testing for breast and ovarian cancer include those who have personal or family history of breast cancer diagnosed before age 50, or ovarian cancer regardless of age; breast and ovarian cancer; male breast cancer; several relatives with breast or ovarian cancer; relatives with BRCA1 or BRCA2 mutation; and breast or ovarian cancer diagnosed in someone of Ashkenazi, or Eastern European, Jewish descent.
Women typically visit the Inland Northwest Genetics Clinic for genetic counseling concerning breast or ovarian cancer because they've been diagnosed with those types of cancer, have a strong family history with them, or are concerned about developing them, Hinds says. The most important tool in estimating a person's cancer risk is their family history, so she draws out a detailed family history that looks at who has had cancer, who hasn't, age of onset of the disease, and whether people have had more thanone type of primary cancer, such as tumors in both breasts. She also asks them about other health concerns, because hereditary cancers can involve problems other than cancer.
Hinds places women in a category of high, moderate, or low risk. If a woman has a high-risk family history but hasn't been diagnosed with cancer, Hinds advises that if another family member has cancer, that person be tested first to find out if an abnormality is present in the family. If the test shows the person with cancer carries a specific BRCA1 or BRCA2 gene alteration, other family members can undergo the test to see if they also have that specific gene change.
The genetic test involves taking a blood sample from the patient. Test results can be positive, meaning a mutation in the BRCA1 or BRCA2 gene was detected; negative, meaning a mutation wasn't found; or uncertain, meaning that a gene change is present, but it's unclear whether that change is - significant or increases a person's cancer risk, Hinds says.
Providence Cancer Center, which operates at both Sacred Heart Medical Center and Holy Family Hospital here, offers genetic testing to high-risk patients, and refers them to Inland Northwest Genetics Clinic for genetic counseling, says Sherri Calhoun, the center's breast-cancer coordinator. Doctors there advise some high-risk patients who have cancer and are planning to undergo a surgical procedure, such as a lumpectomy, to consider having the test beforehand. That way, if the results are positive, they can consider having a mastectomy instead of just having a lumpectomy, and in either case also can consider an oophorectomy (removal of ovaries), Calhoun says. Mastectomies and oophorectomies have a better chance of preventing cancer or a recurrence of it in a high-risk patient than other less-drastic measures.
One of the main concerns patients face when considering genetic testing is the cost, which typically is roughly $3,100, Hinds says. Many health insurers, including Medicare, will pay for the test, but require documentation to prove the patient is high risk, she says.
Other concerns include whether a positive test will lead to discrimination by employers and health, life, and long-term care insurers, Hinds says. Federal law prohibits employers from discriminating when hiring or promoting employees based on genetic test results, she says. In Washington state, insurers for group health insurance can't change rates based on test results, she says. There's a potential risk, however, that test results could affect premiums or availability of life and long-term-care insurance, she says.
Patients decide against the test for other reasons, as well, such as if they don't have female relatives who could be affected by genetic abnormality, or that the results wouldn't change the treatment they've chosen, Nichols says.
Some women with a strong family history of cancer just assume they've inherited a genetic abnormality, while other women simply don't want to know, she says.
"It's a matter of asking, 'How much information do I want to know?"' Nichols says.
A negative test result for a BRCA mutation that's been identified in a relative means that a woman likely has the same risks for breast and ovarian cancer as the general population, Hinds says. That result isn't definitive for everyone, though, because if the family carries another type of high-cancer-risk gene mutation that hasn't been identified, the woman still could have an inherited susceptibility for developing cancer, she says.
Cancer Care Northwest sometimes refers patients whose test results are negative, but who have a high-risk personal or family history, td researchers who are involved in studies of other genetic abnormalities, Nichols says.
If a patient's test is positive, one option is surveillance, which for breast cancer involves more frequent clinical breast exams, mammograms, and in some cases, MRI scans, she says. For ovarian cancer, itincludes more frequent pelvic exams, ultrasounds, and blood tests. Nichols warns that breast tumors must reach a certain size to be detected, though, and that the medical community doesn't have very good screening tools for ovarian cancer. Also, cancers 'caused by inherited genetic mutations tend to be very aggressive, even in early stages, she says.
Another option is chemoprevention, which involves using drugs such as Tamoxifen and Evista. Nichols cautions patients that such drugs only have been shown to prevent what's called estrogen receptor positive tumors, and that a high percentage of tumors caused by inherited genetic mutations are estrogen receptor negative.
Women at high risk for ovarian cancer can take birth control pills, which have been shown to lower the incidence of ovarian cancer, Nichols says. There are concerns, however, that those pills might cause an increased risk for breast cancer, she says.
The best cancer-prevention tool is preventive surgery, although it carries a host of added health implications, she says. Preventive mastectomy and oophorectomy can reduce the risk of breast and ovarian cancer by more than 90 percent, she says. Nichols advises post-menopausal, high-risk patients to have an oophorectomy. Ovary removal in pre-menopausal women is a more complicated matter, because they might not be done having children.
Those women also would need to be on hormone-replacement therapy until they reach menopausal age to offset menopausal symptoms and prevent diseases such as osteoporosis. Such therapy, however, also raises breast cancer risks, she says.
"Making decisions about these procedures is difficult, but they can be lifesaving," Nichols says. "It's important for these high-risk women to understand that it mostly isn't a matter of if they will develop cancer, but when."
Most women who test positive choose to tell family members that they could be at high risk as well, Calhoun says.
"For many patients, one of the main motivators to get the test is because they have daughters or sisters;" she says. "Most people feel an obligation to let their families know."
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