Survivors of non-small cell lung cancer (NSCLC) who never smoked or who are former smokers at the time of diagnosis have a lower risk of developing secondary primary lung cancers (SPLC), according to a recent study.

Researchers found that five years after the initial diagnosis, current smokers were more likely to develop SPLC. The five-year incidence of SPLC was 13 percent for current smokers, seven percent for former smokers, and zero percent for patients who had never smoked.

 "While we believed those who have never smoked would have a low risk of developing a second lung cancer, which was confirmed, we were encouraged to find that smoking cessation led to a lower risk of developing a second lung cancer and overall survival rates similar to nonsmokers," John Michael Boyle, lead author of the study, said in a statement. "These findings confirm that smoking cessation is crucial and should be an integral component of patient care for patients without a prior cancer diagnosis as well as for cancer survivors."

For the study, the research team analyzed 1,484 patients who underwent surgery, with or without adjuvant chemotherapy or radiation therapy, for stage I-IIIA NSCLC at Duke University Medical Center between 1995 and 2008. Of the participants 372 were current smokers, 1,014 were former smokers and 98 of the cohort were never smokers.

 Baseline covariates and oncologic outcomes including local control (LC), development of distant metastases (DM), overall survival (OS) and rates of SPLC were assessed. 

For all patients, there were no differences in LC or DM based on smoking status. However, when comparing patients who were current smokers to those who had never smoked or had quit smoking more than five years prior to surgery, OS was significantly worse for current smokers. 

The abstract, "Tobacco Use and Secondary Lung Malignancies after Surgery for Non-Small Cell Lung Cancer," will be presented in detail during a scientific session at ASTRO's 56th Annual Meeting.