Lung cancer survivors who quit smoking within a year of diagnosis will live for longer than those who continue to smoke, according to new research led by the Universities of Birmingham and Oxford.

The findings also revealed that general practitioners are comparatively less likely to intervene and offer stop-smoking support to cancer patients, than they are to people diagnosed with coronary heart disease. This juxtaposition has resulted in lower quit rates among cancer patients.

The study, conducted in collaboration with the University of Nottingham and funded by the NIHR School for Primary Care Research, calls for better support for cancer patients who need help to quit smoking in the first year following diagnosis.

While just over a third of lung cancer patients were smoking at diagnosis, those who stopped smoking and survived their treatment lived on average for 1.97 years, compared with 1.08 years for those who did not quit smoking after diagnosis, finds the study published in British Journal of Cancer.

Dr Amanda Farley, lead author and lecturer at the University of Birmingham, said "This research indicates that it is never too late to quit smoking. Although many people think that the damage is done, our research shows that even after a diagnosis of lung cancer, people can still benefit from quitting."

In linked research published in the journal Annals of Family Medicine, the researchers also investigate for the first time the likelihood that GPs will offer stop-smoking support, such as advice or medication, in patients with smoking-related cancer who are current smokers at the time of diagnosis, compared with current smokers diagnosed with coronary heart disease.

Using anonymised electronic primary care records of 12,393 people with cancer to identify those who were smoking at the time of diagnosis between 1999 and 2013, the researchers find that GPs record the following on the patient record:

• Patient record updated to reflect smoking status – 37% of cancer patients vs 78% of coronary heart disease patients;
• Patient offered advice to quit – 24% of cancer patients versus 48% of coronary heart disease patients;
• Smoking cessation medication prescribed to patient – 13% of cancer patients versus 22% of coronary heart disease patients.

In the year following diagnosis, around one-third (36.7%) of cancer patients had stopped smoking, compared with almost half (44.4%) of coronary heart disease patients.

While payments to GPs to manage smoking in patients with heart disease, introduced in 2004, led to a sharp increase in GPs recording their patients’ smoking status and giving advice on stopping smoking, the improvement was similar for people with cancer as with heart disease.

Commenting on the research, lead author Professor Paul Aveyard, an Oxfordshire-based GP and Professor of Behavioural Medicine in Oxford University’s Nuffield Department of Primary Care Health Sciences, said: "Our data from these two studies show that cancer patients receive less support to quit smoking from their GP than patients with coronary heart disease, and while absolute quit rates have improved over time they remain lower than they should be.

"While most lung cancer patients who smoke at diagnosis continue to smoke, those who quit in the first year after diagnosis are likely to live for longer and more comfortably after surviving their cancer treatment than those who continue to smoke.’

"Given this finding, cancer patients who smoke would clearly benefit if GPs became more actively involved in offering support to quit smoking as they do with other smoking-related illnesses. To make this a reality for people with cancer, we need research to understand and support GPs to provide the best support possible for patients with cancer to quit smoking."