Lung cancer tied to family risk of other cancers

People who have a first-degree relative with early-onset lung cancer are themselves at heightened risk for developing other types of cancer, according to a new report. The types of cancers involved differ between Caucasians and African-Americans, the researchers found.

Dr. Michele L. Coté, from Wayne State University in Detroit, and associates previously reported evidence of a clustering of lung cancer in families. For their current report, in the medical journal Chest, they examined risk for other cancers among family members of people who developed early-onset lung cancer.

Their study included 673 subjects with lung cancer diagnosed before age 50, as well as 3556 parents and siblings. A randomly selected comparison group of 773 subjects, with information for 3,943 first-degree relatives, served as "controls". Approximately one third of the study population was African-American.

Overall, relatives of the lung cancer case were at almost double the risk for lung cancer compared with "control" relatives. Female relatives also had twice the risk for endometrial cancer.

When analyzed by race, white but not black relatives of people with lung cancer were at heightened risk for endometrial cancer and for any female reproductive malignancy.

In contrast, African-American relatives of lung cancer cases were at significantly higher risk for head and neck cancers, lung cancer, and tobacco-related cancer. The team found that African-Americans had roughly double the risk of these three cancers compared with the white subjects.

The researchers suggest that the familial clustering for different types of cancer and the variation between races may reflect inherited susceptibility.

"Ideally," they add, "knowledge that a family history of early-onset lung cancer may be a risk factor for both tobacco-related and other types of cancers may encourage individuals to adopt healthier behaviors, including smoking cessation and appropriate screening."

SOURCE: Chest, May 2007.