Continued smoking after treatment for lung cancer is a significant predictor of cancer recurrence, concludes a new study presented at this week's American Thoracic Society (ATS) meeting in Denver.
The study took a close look at the factors predicting cancer recurrence in 192 lung cancer survivors (mean age, 62 years; median pack-years of smoking, 56) from three institutions. The subjects had no further evidence of lung cancer after treatment based on both CT and autofluorescent fluoroscopy exams.
For each individual, the investigators collected information on major risk factors, such as smoking status and pack-year exposure, prior cancers, respiratory disease, asbestos exposure, and family history of lung cancer.
Over a mean surveillance period of 8.3 years, 72 (38%) of the 192 patients developed recurrent or another lung cancer, reported lead author Dr. Samjot Dhillon, from Roswell Park Cancer Institute in Buffalo, NY, and colleagues.
The following were statistically significant factors for predicting lung cancer recurrence:
- Recurrence of another nonlung cancer (hazard ratio [HR] = 4.8)
- Presence of a nodule on chest CT, regardless of size or location (HR = 5.2)
- Premalignant lesions on three bronchoscopy exams anywhere in the upper airway (HR = 5.9)
- Pack-years of smoking (HR = 1.01)
Other cancer recurrence, lung nodules on CT, pack-years of smoking history, and persistent premalignant lesions on bronchoscopy were associated with a significant increase in lung cancer recurrence or second primary tumors, the group concluded.
"Along with close medical surveillance for lung cancer recurrence, it is also important for patients to stop smoking as soon as possible since this is a known risk," Dhillon said in a press release. "Every additional pack per year of smoking is associated with further increased risk of cancer recurrence."The results suggest that aggressive ongoing surveillance of lung cancer survivors may be required for long periods of time, the authors wrote in a study abstract. More research on biomarkers of recurrence or second primary tumors is needed to perform targeted interventions in these patients.
