• Cigarette smoking is the primary cause of lung cancer deaths.
• Giving up smoking after a lung cancer diagnosis may lead to a better prognosis, according to a recent study.

Smoking cigarettes is the main risk factor for developing lung cancer and plays a role in more than 80 percent of lung cancer deaths, according to the American Lung Association. A recent research study shows that even quitting smoking after a lung cancer diagnosis may improve a person’s chance of survival.

The study, published in Annals of Internal Medicine, found that people who quit smoke after a lung cancer diagnosis:

• Lived, on average, nearly two years longer than those who kept smoking (6.6 years versus 4.8 years, respectively)
• Had a higher five-year overall survival than those who did not (60.6 percent versus 48.6 percent)
• Had higher progression-free survival (54.4 percent compared to 43.8 percent) — meaning their cancer was less likely to worsen during and after treatment

Behavioral Changes Can Make a Difference

This study is an important new development in the field of lung cancer research, as it shows that behavioral changes after diagnosis can impact outcomes. In an interview with Cure, the study’s lead researcher emphasized that people with lung cancer should feel empowered to make a change. “Even if you get cancer, you can benefit a lot from quitting smoking, so they shouldn’t lose hope,” said Dr. Mahdi Sheikh of the International Agency for Research on Cancer (IARC).

The study — which was set in Moscow — was a culmination of a 15-year long collaborative effort between the IARC and the N.N. Blokhin National Medical Research Centre of Oncology of the Russian Academy of Medical Sciences.

Quitting Smoking vs. Costly Treatments

Dr. Sheikh compared the outcomes of quitting smoking — which he noted is free — to the positive effects of using costly new treatments. “The effect that we saw is comparable to the emerging and new therapeutics for lung cancer that are being investigated, which could cost thousands of dollars and might not be accessible for many patients,“ he told Cure.

The well-established link between smoking and lung cancer deaths led researchers to hypothesize that outcomes could improve for people living with lung cancer if they gave up smoking after diagnosis.

To test their hypothesis, researchers recruited more than 500 individuals who had been diagnosed with early-stage non-small cell lung cancer (NSCLC) and were smokers at the time of diagnosis. They then followed the group over seven years and analyzed disease progression and overall survival in those who had continued to smoke compared to those who had quit smoking.

Dr. Sheikh told Cure that almost 50 percent of people with lung cancer are smokers at the time of their diagnosis. “If we can convince this 50 percent to quit smoking, the ultimate effects on the global burden of lung cancer could be massive,” he said.