A diagnosis of cancer can be like a storm on the horizon, simultaneously threatening the next town as it ravages another. But, like a storm forecast received within enough time for a family to take shelter, early warning about cancer risk can make all the difference in the world. Advances in understanding inherited predispositions to certain cancers are enabling people to obtain testing for the mutations and, if found positive, to take steps to reduce their risk of developing the malignancy.
The wave of the future is using genetics for the prevention of illness, said Ellen Giarelli, RN, EdD, CRNP, associate professor at Drexel Universitys College of Nursing and Health Professions in Philadelphia and president of the International Society of Nurses in Genetics.
Its a powerful tool we have, but its still imperfect, said Duveen Sturgeon, RN, program coordinator for the hereditary colorectal cancer registry at Vanderbilt-Ingram Cancer Center in Nashville, Tenn. We use it as much as we can to guide peoples care and to prevent cancer from happening in family members.
Genetic testing for single-gene disorders commonly is used to determine whether people are at risk of BRCA-associated breast and ovarian cancers, Lynch syndrome (hereditary nonpolyposis colorectal cancer), familial adenomatous polyposis or other rare cancers.
If those mutations are identified with genetic testing, the family members have an opportunity to look at the various things that will help them prevent cancer, said Patricia A. Kelly, DNP, APRN, CNS, AOCN, a genomics consultant at Texas Health Presbyterian Hospital Dallas and coordinator of the Oncology Nursing Society Cancer Genetics Special Interest Group.
About 10% of diagnosed cancers fall into the category of solely hereditary in origin. Single-gene analysis can test for the presence of the mutations. Most of the time, genetic testing is recommended to families who have a conspicuous history across three generations, and a fairly early onset, Giarelli said.
The goal, according to Deborah J. MacDonald, RN, PhD, APNG, assistant professor in the Division of Clinical Cancer Genetics at City of Hope in Duarte, Calif., is preventing cancer from occurring in patients at-risk relatives.
Were moving from the realm of medicine directed toward care of the individual toward [care of]the family, and personalized medicine, MacDonald said. If we can identify individuals and screen appropriately, we can control cancer morbidity and mortality.
With hereditary breast and ovarian cancer, risk reduction may include more frequent screening with MRIs, chemoprevention with tamoxifen, or a bilateral mastectomy or a salpingo-oophorectomy at a certain age, said Bridget LeGrazie, RN, MSN, CNS, APNC, APNG, AOCN, manager of the Cancer Genetics Program at Virtua Fox Chase Cancer Program in Voorhees, N.J., and a member of the ONS Cancer Genetics SIG.
Early detection is key, said Beth Emsley, ARNP, MSN, CBCN, a nurse practitioner at M.D. Anderson Cancer Center in Orlando, Fla. She warned that tamoxifen often is recommended based on studies relating to other breast cancers and taking it is not a guarantee a woman with a BRCA 1 or 2 mutation will not develop cancer.
Giarelli cautions that prophylactic surgery does not entirely eliminate the risk. There is no way the pathologist or surgeons can be absolutely sure they have removed every single cell, she said. Whatever cell is left behind has the potential of becoming cancer, because it houses that mutation.
Lynch syndrome patients may opt for more frequent colon cancer screening or a sub-total colectomy. Care also might include a prophylactic hysterectomy to decrease the risk of endometrial cancer and tests to monitor for other cancers associated with the syndrome, Sturgeon said.
Familial adenomatous polyposis results in excessive polyp growth, from hundreds to thousands in the colon. Depending on the number of polyps in the colon, frequent colonoscopies coupled with polypectomies and medication such as sulindac may delay surgery until early adulthood, but eventually the patient may need definitive surgery such as a total colectomy with an ostomy or an ileorectal anastomosis, Sturgeon said. If left untreated the risk for colon cancer approaches 100% by the age of 40.
Multiple endocrine neoplasia type 2A puts people at 100% risk of developing medullary carcinoma of the thyroid and also at risk of developing adrenal tumors. Typically, patients receive enhanced surveillance for a biomarker for an adrenal tumor. These patients also might have a thyroidectomy before cancer develops. Researchers are continuing to assess the genetic mutations associated with the development of other cancers.
Obstacles and concerns
Some people at risk of cancer because of a family history of the disease do not want testing, and, Kelly said, nurses must respect that decision.
Nurses have to protect patients right to chose the right option for themselves, without any coercion, Giarelli said, adding nurses must ensure patients understand all of the risks, including anxiety or regrets that might develop by learning the genetic information and how that might affect family dynamics.
Although the Genetic Information Nondiscrimination Act of 2008 mandates health insurers and employers not discriminate based on genetic testing, the fear still exists. And Giarelli said, rightly so, because despite peoples best efforts, it is impossible to ensure information will stay confidential. Breeches do occur.
GINA does not include life or disability insurance, Sturgeon said, and that concerns some individuals.
Insurers typically will cover genetic testing if it falls under National Comprehensive Cancer Network guidelines, Kelly said, but high deductibles may deter people from pursing testing.
Emsley, on the other hand, said she often finds patients so interested that they will pay for testing privately, at a cost of about $3,500. However, she said other people do not want to know. People are scared, she said. Either way, Emsley encourages involving a genetic counselor to help guide people.
Single nucleotide polymorphisms profiles to evaluate risk for breast or prostate cancers not associated with single-gene mutations have become available, including through direct-to-consumer marketing.
It holds promise for individualized treatment, but it needs to be evaluated in the context of other aspects of the patients history, said Kelly, who recommends people with concerns seek counseling from a genetics professional, rather than purchasing a kit.
Testing without counseling is a disservice to the patient, because they dont have an opportunity to assess risk and how it will impact the family if they are high risk, LeGrazie said. A counselor can get them where they need to go to get a plan of care.
Oncology nurses roles
Nurses should learn more about hereditary predispositions to cancer and the red flags in a family history to know when to refer to a genetic specialist, Kelly said, adding, All nurses need to become familiar with the genetic/genomic language and to understand their role.
Giarelli agreed, saying nurses caring for a patient with cancer should take a three-generation cancer history with the age the cancer occurred.
A good family history is within the grasp of all nurses and should be part of our assessment, Sturgeon added. Nurses can recognize cancer in a family and refer to a genetic counselor or nurse practitioner for a work up.
ONS recommends all nurses have a basic knowledge of cancer and genetics, and it offers education in the specialty, as do some colleges. MacDonald said nurses need a foundation in genetics, but more formal training is needed. Nurses are the most important healthcare providers to learn as much as they can about genetics, because they see patients more and are respected and trusted, Giarelli said. Patients will be looking to nurses to help them make sense of genetics, and nurses will be instructing patients in the basic concepts, so they can make informed choices.