According to cancer researchers at UT Southwestern Medical Center, individuals who have inherited a certain gene mutation have a greater chance of getting lung cancer, even more so than individuals who are heavy smokers or individuals without this mutated gene. Both men and women have an equal risk of inheriting the mutation, however, women are more likely to develop lung cancer, even when they have never smoked.
Researchers have found that the Epidermal Growth Factor Receptor (EGFR) gene can carry a rare inherited T790M mutation that provides for a one-in-three chance of developing lung cancer in individuals who have never smoked. This is considerably greater than the average heavy smoker who has a one-in-eight chance of developing lung cancer. In fact, about a forty-fold greater risk than individuals who have never smoked and don’t have the T790M mutation. Since this risk is so great for these individuals, it has been suggested that they get screened at regular intervals, says Dr. Adi Gazdar, Professor of Pathology and Deputy Director for the Nancy B. and Jake L. Hamon Center for Therapeutic Oncology Research at UT Southwestern.
Gazdar notes, “Fortunately the mutation, which is extremely rare, can be detected by a blood test. Only people suspected of having the mutation and their family members need to be tested for the mutation. This is a very rare inherited mutation in the general population, but because it confers a greatly increased risk of developing lung cancer, it is present in about one in every hundred lung cancer cases.”
Gazdar and Dr. Joan Schiller, Professor and Chief of the Division of Hematology-Oncology in Internal Medicine and Deputy Director of UT Southwestern’s Harold C. Simmons Comprehensive Cancer Center, discovered these findings by studying a women with lung cancer and her family for five generations as well as reviewing information in the literature. Gazdar notes, “It’s rare, but you’re still faced with families like this. As people get more attuned to recognizing lung cancer patients with this mutation, we’re going to be identifying more family members with this inherited risk, and we will have to develop guidelines on how to manage them.”
As the T790M mutation was first discovered in the patient’s lung cancer and then later in blood, this prompted an investigation that involved blood tests of family members and piecing together medical and smoking histories of family members for five generations, some of whom were deceased, by Linda Robinson, Assistant Director of Cancer Genetics. Researchers found that T790M was passed down on the mother’s side.
The National Cancer Institute reports that lung cancer is the leading cause of death in the U.S. In fact, approximately 160,000 individuals in the U.S. died from lung cancer in 2013. This is a greater number of deaths than from breast, colorectal and prostate cancer combined.
The research findings are available in the April edition of Journal of Thoracic Oncology. The same issue provides another article with additional information confirming the research done by UT Southwestern investigators.