Early detection of COPD is important for lung cancer surveillance.

It is well known that chronic obstructive pulmonary disease (COPD) is a significant risk factor for lung cancer. Approximately 1% of COPD patients develop lung cancer every year, which may be associated with genetic susceptibility to cigarette smoke. Chronic inflammation caused by toxic gases can induce COPD and lung cancer. Inflammatory mediators may promote the growth of bronchioalveolar stem cells, and activation of nuclear factor-κB and signal transducer and activator of transcription 3 play crucial roles in the development of lung cancer from COPD. Low-dose computed tomography (LDCT) is an effective procedure for the early detection of lung cancer in high-risk patients. However, determining which patients should be screened for lung cancer in a primary care setting is difficult. In this article, we review the epidemiology and aetiology of lung cancer associated with COPD, verify the efficacy of lung cancer screening by LDCT, and discuss the importance of early detection of COPD for lung cancer surveillance. We propose that, for the prevention of both diseases, COPD screening in smokers should be initiated as early as possible, so they can stop smoking and so that candidates for an efficient lung cancer screening programme can be identified.