A prospective cohort study found that quitting smoking after being diagnosed with early-stage non-small cell lung cancer may slow disease progression and decrease mortality.

Given that about half of all smokers continue to smoke after a lung cancer diagnosis, these findings present an opportunity to improve overall and progression-free survival in this type of cancer.

The study is published in Annals of Internal Medicine.

More than 80% of patients with non-small cell lung cancer have a history of smoking, and about half are current smokers at the time of diagnosis.

There is limited evidence that smoking cessation may improve survival, so many patients may feel it is too late to quit once they've been diagnosed with lung cancer.

Researchers from the International Agency for Research on Cancer, the specialised cancer agency of the World Health Organization, in collaboration with the N.N. Blokhin National Medical Research Centre of Oncology in Russia, recruited 517 adults who currently smoked when diagnosed with early-stage non-small cell lung cancer from 2 sites in Moscow, Russia to determine whether quitting smoking after diagnosis affects the risk for disease progression and mortality.

The participants were interviewed at the start of the study to ascertain medical and lifestyle history, including tumour characteristics, and the amount of lifetime smoking, and then followed each year for an average of 7 years to record any changes in their smoking behaviour, treatments, and disease status.

Of 517 patients who were smoking when diagnosed with lung cancer, less than half quit (44.5%), and very few relapsed.

The patients who quit smoking were more likely to live longer overall (6.6 years vs. 4.8. years), live longer without lung cancer (5.7 vs. 3.9 years) and have a longer time to death from lung cancer (7.9 vs. 6 years).

According to the authors, these results show that even after being diagnosed with lung cancer, there is still significant benefit to quitting smoking.

Physicians should make their lung cancer patients aware that quitting smoking can extend life overall and extend life without cancer recurrence.

Source: American College of Physicians