PURPOSE: Our observation that many LC patients stop smoking prior to diagnosis, often preceding clinical symptoms and without difficulty, led us to speculate that smoking cessation may be a presenting symptom of the disease.
METHODS: Patients with LC, prostate cancer (PC) and myocardial infarction (MI), were interviewed about smoking habits up to the time of diagnosis. Severity of nicotine addiction at time of heaviest smoking was measured using the Fagerström Test for Nicotine Dependence (FTND: range 0–10). Intervals between smoking cessation, onset of symptoms, and diagnosis were recorded. Difficulty quitting was rated on a scale of 0–10.
RESULTS: Among 115 LC patients, 60 were current and 55 former smokers. Only 11% of former smokers were symptomatic at quitting. Among 101 PC patients, there were 21% never, 32% current and 47% former smokers. Among 99 MI patients, there were 15% never, 59% current and 26% former smokers. The median interval from cessation to diagnosis was 2.7 yr for LC, 24.3 yr for PC and 10.0 yr for MI patients (p<0.0001). The median FTND for LC patients was 7.0 for both current and former smokers; for PC patients it was 7.0 for current vs 3.0 for former smokers (p=0.0004); for MI patients it was 6.5 for current vs 4.0 for former smokers (p=0.011). Seventeen of the LC patients (31% of former smokers) rated their difficulty quitting as 0/10. Among LC patients, there was no significant difference in stage distribution, histology or survival of current vs former smokers.
CONCLUSION: 48% of LC patients had stopped smoking prior to diagnosis. Only 11% of these were symptomatic at quitting. Unlike PC or MI, LC patients who quit smoking were as dependent on nicotine (when smoking most heavily) as those who continued to smoke, and despite this, many quit without difficulty.
CLINICAL IMPLICATIONS: These results refute the notion that lung cancer patients usually quit smoking because of disease symptoms. The hypothesis that smoking cessation, especially without difficulty, is a presenting symptom of lung cancer warrants further investigation.
DISCLOSURE: Barbara Campling, No Financial Disclosure Information; No Product/Research Disclosure Information