Lung cancer is one of the most common causes of death from cancer worldwide. Smoking induces and aggravates many health problems, including vascular diseases, respiratory illnesses and cancers. Tobacco smoking constitutes the most important risk factor for lung cancer. Most people with lung cancer are still active smokers at diagnosis or frequently relapse after smoking cessation. Quitting smoking is the most effective way for smokers to reduce the risk of premature death and disability. People with lung cancer may benefit from stopping smoking. Whether smoking cessation interventions are effective for people with lung cancer and whether one method of quitting is more effective than any other has not been systematically reviewed.
To determine the effectiveness of smoking cessation programmes for people with lung cancer.
We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (accessed via PubMed) and EMBASE up to 22 June 2015. We also searched the American Society of Clinical Oncology (ASCO) Annual Meeting proceedings, the lung cancer sections of the proceedings of the ESMO Congress, the lung cancer sections of the proceedings of the European Conference of Clinical Oncology (ECCO) Congress, the World Conference on Lung Cancer proceedings, the Society for Research on Nicotine and Tobacco Annual Meeting from 2013, the Food and Drug Administration website, the European Medicine Agency for drug registration website, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal, ClinicalTrials.gov, and the metaRegister of Controlled Trials (mRCT) to 1 July 2015. We applied no restriction on language of publication.
We planned to include any randomised controlled trial (RCT) of any psychosocial or pharmacological smoking cessation intervention or combinations of both, compared with no intervention, a different psychosocial or pharmacological (or both) intervention or placebo for pharmacological interventions in people with lung cancer.
Two review authors independently screened the studies from the initial search for potential trials for inclusion. We planned to use standard methodological procedures expected by Cochrane. We found no trials that met the inclusion criteria.
We identified no RCTs that met our inclusion criteria. Among the 1052 records retrieved using our search strategy, we retrieved 13 studies for further investigation. We excluded 10 trials: five trials because we could not distinguish people with lung cancer from the other participants, or the participants were not people with lung cancer, four because they were not randomised, or RCTs. We excluded one trial because, though it was completed in 2004, no results are available. We assessed three ongoing trials for inclusion when data become available.
There were no RCTs that determined the effectiveness of any type of smoking cessation programme for people with lung cancer. There was insufficient evidence to determine whether smoking cessation interventions are effective for people with lung cancer and whether one programme is more effective than any other. People with lung cancer should be encouraged to quit smoking and offered smoking cessation interventions. However, due to the lack of RCTs, the efficacy of smoking cessation interventions for people with lung cancer cannot be evaluated and concluded. This systematic review identified a need for RCTs to explore these.