Saturday, December 20, 2014
Genetics of Lung Cancer
My father developed lung cancer at the age 59. He was a nonsmoker, never consumed tobacco and was not exposed to radon and asbestos as far as I know. He had been using immunosuppressants all his life. My grandfather died of cancer before 50. All of my father`s step brothers are still alive and healthy. None of them has developed cancer. There is no history of cancer on my mother`s side of the family. Am I at a risk of developing cancer?
Research suggests that having a family history of cancer predisposes close relatives (children, brothers and sisters) to the same kind of cancer. This would mean that you have a somewhat higher chance of developing lung cancer than the average individual your age. Most estimates are that lifetime cancer risk is about doubled; this applies to lung cancer as well as most other cancers. The fact that your father was using immunosuppressants may have contributed to his cancer risk; it is difficult to take this information into account in estimating a cancer risk for you.
The lifetime risk to develop lung cancer for Americans is about 7%; however, the majority of individuals who develop lung cancer are smokers so the risk for a non-smoker is probably somewhat less. But if you use the population risk for lung cancer, your chance will be somewhere around 10-12%.
Currently, there are no recommendations for lung cancer screening, and there are no identified gene mutations which are helpful in estimating one's risk of developing lung cancer. Lung cancer is sometimes found in some of the hereditary cancer syndromes, but the information you provide about other cancers in the family is not highly concerning.
Your best option is to discuss your family history with your primary care physician and work with him or her to come up with an appropriate screening plan for the most common cancers for your age, race and gender. These are generally colon cancer, female breast cancer and prostate cancer. You can also try to minimize your exposure to known environmental factors associated with increased cancer risk (such as cigarette smoke). If you wish to discuss the possibility of a genetic influence in your family, you can contact a genetic counselor in your area and schedule an appointment to go over this information in more detail. The websites for the National Society of Genetic Counselors and the National Cancer Institute are listed below.
Duane D Culler, PhD, MS
Clinical Instructor of Genetics
School of Medicine
Case Western Reserve University