According to the American Cancer Society, skin cancer is the most common form of cancer. In fact, nearly half of all cancers are some form of skin cancer. The different forms of skin cancer are basal cell, squamous cell and melanoma. Melanoma is considered the most serious form of skin cancer.
The majority of cancers occur with no specific explanation but may be due in part to environmental factors. However, about 5 to 10 percent of all cancers are hereditary and linked to genes that are passed from one generation to the next in a family. Genes have been discovered that are associated with the formation of melanomas. One of these genes is called p16. Mutations in the p16 gene cause about 20 to 40 percent of hereditary melanomas. Individuals who inherit a p16 mutation have an increased risk to develop melanoma. Researchers have found that the risk to develop pancreatic cancer is also increased in individuals who have a p16 mutation.
Families that have more than one relative with melanoma are considered “at-risk” to have a p16 mutation. Families are also considered “at-risk” to have a p16 mutation if there are relatives with melanoma and pancreatic cancer. Genetic testing to detect p16 mutations is available for “at-risk” families. Genetic testing involves isolating and analyzing the p16 gene from cells found in a blood sample. Someone who has a p16 mutation is more likely to get cancer than someone who does not have the mutation. However, having the mutation is not a 100% guarantee that cancer will occur. Recommendations for cancer screening and medical management can be based on genetic test results and family history.
Genetic testing for Hereditary Melanoma is not routinely ordered unless there is a family history that suggests the presence of a p16 mutation. Typically, the first person to undergo genetic testing in the family is a relative who has had cancer. Therefore, a family member with melanoma or pancreatic cancer should be tested before testing other family members who have not developed cancer.
Although genetic testing for cancer risk has implications for the entire family, the decision to test is personal and should be carefully considered. Genetic testing can be discussed with a specialist, such as a cancer genetic counselor, who is familiar with hereditary cancer syndromes. If you are concerned about your family history of melanoma or of any other cancers, call 703-776-8748 to speak with Grace-Ann Fasaye, Certified Genetic Counselor and Manager of Cancer Genetic Services at Inova Fairfax Hospital.