Negative lung cancer CT scans did not increase smoking relapse

Consistently negative CT scans for lung cancer were not associated with reduced long-term smoking abstinence or increased smoking relapse.

Researchers examined data from participants of the Early Lung Cancer Action Program who had negative CT scans. The researchers looked at point and prolonged abstinence in 730 baseline smokers, and relapse in 1,227 smokers who quit at least one year before enrollment, 121 recent quitters and 155 baseline smoker who quit during follow-up.

The likelihood of achieving point abstinence was 28% less among participants who had a negative CT scan compared with those who had a noncancer–positive scan (P<.004). This was no longer statistically significant, however, by the sixth year of follow-up, suggesting a positive scan may lead to a higher quitting rate in the short-term but the effect on cessation may lessen with time, according to the researchers.

In the long-term, a consistently negative CT scan was not associated with likelihood of relapse for participants who were long-term abstinent at baseline; those who had quit 30 days to 12 months before enrollment; and those who quit during follow-up.

Additionally, there was no significant difference between those with positive scans and those with negative scans for likelihood of relapse among recent quitters or baseline smokers who quit during the study.

“Consistent with the absence of a longer-term effect on cessation, prolonged abstinence is not statistically different for those with a consistently negative scan and those with a positive screening result, suggesting that the reassurance provided by a negative scan may not be a factor determining long-term abstinence,” the researchers said.

Anderson CM. Cancer Epidemiol Biomarkers Prev. 2009;doi:10.1158/1055-9965.EPI-09-0176.