Non-Smokers with lung cancer respond better to treatment than smokers

Smoking history contributes to poor outcomes in the treatment of lung cancer, according to a new study. Non-small cell lung cancer (NSCLC) lung cancer patients who have never smoked before in their life have better overall survival rates and respond better to chemotherapy than current or former smokers.

Published in the June 1, 2006 issue of CANCER, a peer-reviewed journal of the American Cancer Society, the study also reveals that smoking status during treatment has no affect on clinical outcome.

Cigarette smoking is the most significant risk factor for developing lung cancer, one of most common and aggressive malignancies in the world. In 2005, over 170,000 Americans were diagnosed with lung cancer and over 160,000 patients died. The five-year survival rate from lung cancer is less than 20 percent at best. NSCLC causes the majority of lung cancers, and if cured, the survivor has up to a 4 percent annual risk of developing another tumor.

Despite the association of lung cancer with cigarettes, diagnosed patients continue to smoke. However, physicians remain unable to tell their patients how that will impact their cancer treatment. Previous studies have failed to agree on whether smoking status impacts the outcome of chemotherapy or chemotherapy and thoracic irradiation.

Led by Anne S. Tsao, M.D. of the University of Texas M. D. Anderson Cancer Center in Houston, researchers reviewed the medical records of 1370 patients with NSCLC who were treated with chemotherapy or chemo-radiation to determine an association between smoking and treatment response and survival.

The researchers found that patients who never smoked had a better response to the chemotherapy; developed less disease progression during therapy; and showed improved survival over former and current smokers. They say the finding may be due to non-smokers having less genetic damage compared to smokers, being less likely to have other ailments that would affect survival, and having better preserved lung function. The authors write that "Continued efforts at preventing smoking initiation are a critical public health issue and emphasize the need for chemoprevention for smokers and primary-prevention protocols to prevent smoking."