Sex and gender differences in non-small cell lung cancer.

Historically, lung cancer has been viewed as a male disease, but during the past 50 years there has been a dramatic increase in the incidence of lung cancer in women. Lung cancer is currently the most common cause of cancer death in American women, accounting for more than one quarter of all cancer deaths. This has been attributed to a significant increase in tobacco consumption by women; however, approximately 1 in 5 women with lung cancer never smoked. As the incidence of lung cancer in women has increased, significant gender-based differences in epidemiology, biology, and treatment responses have become evident and warrant further investigation to advance the treatment of lung cancer in all patients.