Patients with non-small cell lung cancer (NSCLC) who have quit smoking or never started in the first place have a lower risk of developing secondary primary lung cancers than NSCLC patients who keep smoking, according to a study presented at the just-completed American Society for Radiation Oncology (ASTRO) meeting.
Current smokers were more likely to develop secondary primary lung cancers five years after their original diagnosis, the study team from Duke University reported.
The researchers examined the association between smoking history and the risk of developing secondary tumors that are unrelated to the original tumor based on histology and location in the lung. They analyzed the records of 1,484 patients, including 1,014 former smokers and 98 who had never started, all of whom underwent surgery with or without chemo or radiation therapy between 1995 and 2008.
The five-year incidence of secondary cancers was 13% for current smokers and 7% for former smokers, while no patients without a history of smoking developed a secondary tumor in five years, though one did in seven years. For continuing smokers, the risk of secondary pulmonary lung cancers rose 8% per 10 pack-years, the group reported.
Lead author Dr. John Boyle said they were encouraged to find that smoking cessation led to a lower risk of developing a second cancer, as well as overall survival rates similar to those for nonsmokers.