Family History & Lung Cancer

Lung cancer is generally linked with environmental factors and certain behaviors, such as smoking and repeated exposure to radon gas, asbestos, air pollution and secondhand smoke. However, family history and genetics have been shown to contribute to the possibility of developing lung cancer. These findings suggest that certain genetic sequences, which could be identified, may heighten the risk for lung cancer regardless of external factors. Genetic tests can be given to individuals who have a family of history of lung cancer to test for genetic predispositions to the disease.

Family History

• According to the CDC, having first degree family members with lung cancer (parents, siblings or children) doubles an individual's chance of developing lung cancer later in life. Smokers or those exposed to carcinogenic compounds (e.g., asbestos and secondhand smoke) are less likely to have genetic predispositions to the disease. Non-smokers who develop lung cancer, however, are more likely to carry genetic factors that lead to the development of lung cancer.

Race and Ethnicity

• Different ethnic groups and races have significantly different rates of developing lung cancer. This could be the result of biological and genetic differences in different ethnic groups, which affect how individuals react to toxins, medication and treatment. In one study, Japanese Americans and Latinos were half as likely to develop lung cancer than Caucasians with similar smoking habits. African Americans and ethnic Hawaiians with similar habits, however, were twice as likely than Caucasians to develop lung cancer.

Gender and Age

• Lung cancer is the leading cause of cancer death in women in the United States, exceeding the mortality rate for breast cancer. Lung cancer is generally more common in men than in women. This is thought to be due to the fact that there are more men smokers and women smokers. Lung cancer is common in men over 40 years old but is more common in the elderly. The average age of both men and women diagnosed with lung cancer is 70.

External and Genetic Factors

• Lung cancer is related to genetic factors.

  A 2008 NIH study of 5,000 smokers showed that while the major risk factor for lung cancer is exposure to tobacco smoke, only about 11 percent of tobacco users develop lung cancer. This leads to the assumption that genetic factors play a key role in the development of this disease. The study also showed that those with a family history of lung cancer have a 2.5 times more chance of developing the disease.

Extended Family Risk Factors

• Family members beyond the first degree who have lung cancer (grandparents, aunts, uncles and cousins) generally have a lower impact on the chances of developing the disease. The risk factor is approximately 1.2 times higher for an individual if one of the above listed family members has the disease.