The Cancer Institute at Alexian Brothers Hospital Network Broadens Genetics Testing
June 25, 2007 - The Cancer Institute at Alexian Brothers has introduced a new genetics test for hereditary melanoma and pancreatic cancer and an expanded genetics test for hereditary non-polyposis colorectal cancer, also known as Lynch Syndrome.
Both tests can alert individuals to a genetic predisposition toward cancer, empowering them to take steps to reduce the risk of cancer, to tell loved ones who might share the same risk, and to detect cancer early if it occurs. "With melanoma or any cancer, the earliest diagnosis has the best outcome," says Tinamarie Bauman, R.N., M.S.N., A.P.N.G.,Advanced Practice Nurse at The Cancer Institute.
The MELARIS® test for hereditary melanoma and pancreatic cancer seeks to identify mutations in the p16 gene, which cause most cases of hereditary melanoma and increase the risk of pancreatic cancer in some families. People with a p16 mutation have up to a 76 percent chance of developing melanoma by 80, and up to a 50 percent chance of developing melanoma by 50, Bauman says. In some families, she adds, people with a p16 mutation have up to a 17 percent chance of developing pancreatic cancer by 75. These p16 mutation risks compare with the general population's 1 percent risk of melanoma by 80, less than 1 percent risk of melanoma by 50, and 1 percent risk of pancreatic cancer by 75.
The MELARIS test is recommended for individuals with a family history of melanoma or pancreatic cancer or a personal history of melanoma, including multiple moles identified asmelanoma. If the test reveals a p16 mutation, the prescribed course of action usually includes increased skin exams, including self-exams and exams by a doctor, and lifestyle modifications, including reduced exposure to the sun and avoidance of other sources of ultraviolet radiation, such as tanning beds. Carriers of the p16 mutation "must wear protective clothing,wide-brimmed hats, sunglasses, and long sleeves,"Bauman says. "They really need to cover as much of their skin as possible. They also must wear sunscreen of 15 SPF or higher all the time to prevent sunburn."
Physicians take an especially aggressive approach to removing and performing biopsies on suspicious moles when a person has a p16 mutation, Bauman says.Discovery of the mutation also can affect medical management for the person's children, parents and siblings, who have a 50 percent of having the same mutation."Doctors will do more frequent exams for these types of families, especially during puberty or pregnancy because moles are changing rapidly then,"Bauman says. The expanded COLARIS® genetics test for Lynch Syndrome includes fullsequence analysis of the MSH6 gene.
Mutations in this gene are responsible for 10 percent to 15 percent of all gene mutations related to Lynch Syndrome. The test already included analysis for mutations in the MLH1 and MSH2 genes, which also have been linked to the disease. The test is recommended for individuals with a personal or family history of colorectal, endometrial, ovarian or gastric cancer, particularly when cancer has struck before 50, Bauman says. Genetic tests such as COLARIS and MELARIS involve drawing blood, from which DNA is extracted and analyzed. If gene mutations are found, the patient can meet with one of The Cancer Institute's medical oncologists to discuss possible courses of action. The Cancer Institute also offers risk assessments and genetic testing for breast cancer and other cancers. Like other medical tests, genetic tests cannot offer 100 percent detection, but they can help people better understand their risk of cancer and use that knowledge to their advantage, Bauman says.
