Cancer screening and diagnosis: opportunities for smoking cessation intervention.

The article by Westmaas et al that accompanies this editorial demonstrated an increased rate of smoking cessation among Cancer Prevention Study II participants who were diagnosed with cancer as compared with those without cancer diagnoses. The authors concluded that cancer diagnosis provides a teachable moment for smoking cessation (teachable moment is described by McBride et al as “life transitions or health events thought to motivate individuals to spontaneously adopt risk-reducing health behaviors”). The clinical relevance of cessation at diagnosis is suggested by meta-analyses demonstrating that the relative risk of cancer-specific mortality among current smokers is 1.6 relative to never-smokers; by comparison, the relative risk for former smokers is 1.03 relative to never-smokers. One may conclude that cessation at diagnosis will decrease the relative risk of an individual. However, the improvement in prognosis as a result of cessation at diagnosis is subject to variation as a result of longitudinal smoking status, lifetime exposure, and other important variables. Definitive population-level conclusions are difficult, in part because randomized trials of cessation among patients with newly diagnosed cancer are challenging to conduct, and many observational studies have not collected or adjusted for smoking status or other variables during follow-up. One reason that follow-up assessment is important is the finding by Westmaas et al of a 12% rate of smoking resumption among cancer patients who quit smoking at diagnosis. Thus, although Westmaas et al provide robust evidence that cessation is more likely after diagnosis, important research remains to be conducted regarding the impact on long-term outcomes of smoking and smoking cessation at the time of diagnosis. Data are sufficient, however, to conclude broadly that quitting smoking improves the prognosis of patients with cancer. It is notable that this increase in cessation was evident despite the exclusion of several of those cancer sites most strongly related to smoking. The authors excluded cancers of the esophagus, head, neck, and lung, based on the idea that those cancers would more likely produce symptoms that might lead to cessation, whereas the aim was to measure the spontaneous cessation attributable to patients being told that they had cancer. One might argue whether that exclusion is appropriate. Many cancers and many cancer therapies produce symptoms that might make smoking more difficult or less palatable. Furthermore, a tobacco-related cancer diagnosis would arguably be more likely to motivate cessation, even in the absence of symptoms. In any case, diagnosis may provide a teachable moment even if the cancer or treatment symptoms are the cause of increased motivation to quit. The Westmaas et al finding of higher cessation rates among individuals diagnosed with cancer raises the question of whether cessation rates are also higher after cancer screening. This question is timely, given the current rapid expansion of low-dose computed tomography (LDCT) screening for lung cancer. In 2011, the National Lung Screening Trial found that LDCT screening was associated with a reduction of lung cancer mortality of approximately 20% among long-term cigarette smokers. In 2013, the US Preventive Services Task Force recommended LDCT lung cancer screening for high-risk individuals. Recently, the Centers for Medicare and Medicaid Services announced the decision to provide Medicare coverage for lung cancer screening. There is a large potential for growth in both the number of patients who will receive LDCT lung cancer screening and the number of clinics that will offer the service when Medicare and private insurance plans begin to cover this service (as required by the Affordable Care Act). An estimated 8.6 million Americans were eligible for LDCT screening as of 2010. In lung cancer screening studies, approximately 50% of participants were current smokers. As of October 2014, the American College of Radiology had designated only 280 sites as lung cancer screening centers of roughly 6,700 sites that had been accredited in the chest computed tomography module, which indicates that there may be a large number of centers that are developing the facilities to provide LDCT. LDCT screening for lung cancer provides a crucial opportunity for smoking cessation intervention. The Public Health Service–sponsored “Treating Tobacco Use Guideline” states: “It is essential that clinicians and health care delivery systems consistently treat every tobacco user seen in a health care setting. ” There is support from professional organizations and insurers for LDCT sites to provide cessation. The American College of Radiology designation as a lung cancer screening center requires an attestation that “a mechanism [. ] be in place to refer patients for smoking cessation counseling or to provide smoking cessation materials. ” Medicare coverage will require that patients receive a written order from a clinician after a shared decision-making visit. That visit must include brief cessation counseling and furnishing of information about tobacco cessation interventions. Within 5 years after cessation, the reduction in lung cancer mortality (compared with continuing smokers) is similar to that associated with LDCT screening; after 20 years, the reduction in lung cancer mortality is much larger (eg, 87% reduced risk among women in the Nurses’ Health Study). JOURNAL OF CLINICAL ONCOLOGY E D I T O R I A L VOLUME 33 NUMBER 15 MAY 2