Surgery could extend the lifespan for patients with advanced lung cancer, a new study finds.

Non-small cell lung cancer, which is the most common form of the disease, is the leading cause of cancer death, and kills more than 1.4 million people worldwide each year.

Treatments for this form of cancer include surgery, chemotherapy and radiation. But, while chemotherapy treatment is increasing, surgery is decreasing, University of California researchers at Davis say.

They looked at a registry of more than 34,000 patients with this type of lung cancer, and found that those who underwent surgery had improved survival rates compared to their non-surgical peers.

The researchers found that 25.7 percent of patients were given a combination of chemotherapy and radiation, while 11 percent received surgery, either alone or in combination with other therapies. They also found that 27 percent of patients received no treatment at all.

Surgery had a dramatic impact on overall survival.  The median overall survival for patients who received chemotherapy and surgery was 40.7 months. The median was 33.3 months for patients who received chemotherapy, radiation and surgery; 28.8 months for those who only received surgery; and 18.6 months for surgery and radiation, they found.

For patients who were not treated surgically, those who received chemotherapy and radiation had a median overall survival of 11.9 months; chemotherapy alone was 10.5 months; radiation alone was 3.7 months.

The researchers say they are concerned about the disparity of care – especially for the more than one-quarter of patients who received no treatment – but more study is needed to find out more information about the decision-making involved.

Surgery is not right for all patients with advanced-stage lung cancer, but we want to ensure that patients are being evaluated appropriately. We want to see if we can create a decision tool that helps physicians decide who is suitable for surgery,” says Elizabeth David, the lead author of the study, which appears in The Annals of Thoracic Surgery.