Smoking cessation reduces mortality among patients receiving active screening for lung cancer

Patients who quit smoking while enrolled in a low-dose CT screening program experienced a notable decrease in mortality compared with persistent smokers, according to study results presented at the World Conference on Lung Cancer.

No previous study has analyzed the influence of smoking cessation on low-dose CT screening outcomes, according to the researchers.

“In the last 15 years, we have been involved in several trials for early detection in heavy smokers or former smokers at high-risk for lung cancer,” Ugo Pastorino, MD, director of thoracic surgery at Fondazione IRCCS Istituto Nazionale dei Tumori in Milan, said during a press conference. “These are long-term smokers, and the usual concept is that these individuals are resistant to quitting.”

Pastorino and colleagues evaluated data from 3,381 smokers enrolled in two low-dose CT screening studies between 2000 and 2005. The researchers categorized participants as current smokers or former smokers. Former smokers included ex-smokers who independently stopped smoking prior to entering randomization, as well as those who quit smoking during the screening process.

The median follow-up was 8.7 years.

Twenty-eight percent of baseline smokers quit during the screening period, according to Pastorino.

Overall, 151 deaths occurred in the smoking group and 109 deaths occurred in the group that stopped smoking.

Former smokers experienced a 26% decrease in mortality compared with current smokers (RR = 0.74; 95% CI, 0.58-0.95). When the researchers limited the comparison to former smokers who quit more than 2 years prior to the end of follow-up, the decrease in mortality rose to 39% (RR = 0.61; 0.46-0.8).

Patients who quit during the course of the study experienced a 43% mortality reduction (RR = 0.57; 95% CI, 0.38-0.85).

Pastorino noted that participants who received pharmacological intervention were more likely to quit smoking; however, he acknowledged that only a small percentage of patients received pharmacological support, and that its widespread utilization was unlikely due to lack of endorsement.

“Stopping smoking reduces total mortality by over 25% — it could be even over 40%,” Pastorino said. “The benefit is three- to fivefold greater than the benefit in the National Lung Screening Trial, the largest U.S. screening trial. In my view, the next step is to test prevention vs. screening, or how to best incorporate prevention through stopping smoking and screening.” – by Cameron Kelsall

Reference:

Pastorino U, et al. Stopping Smoking Reduces Mortality in Low-Dose Computed Tomography (LDCT) Screening Volunteers. Presented at: 16th World Conference on Lung Cancer; Sept. 6-9, 2015; Denver, Colorado.

Disclosure: HemOnc Today was unable to obtain a list of the researchers’ relevant financial disclosures at the time of reporting.