Study: Tuberculosis Patients Have Higher Lung Cancer Risk

A new research conducted by China Medical University concluded that patients suffering from tuberculosis are at higher risk of developing lung cancer.

To date, no clear association between tuberculosis and lung cancer has been established, but this new study brings evidence of an increased lung cancer risk in people with TB.

One of the researchers, Dr. Chih-Yi Chen, said that “tuberculosis is a very common chronic disease worldwide; people in the developing and undeveloped areas suffer with it mostly.

“It is well known that lung cancer is causally associated with smoking.

“Less attention has been focused on whether people with tuberculosis are also at higher risk of developing lung cancer.”

One million patients covered under the country's National Health Insurance (NHI) program, were randomly selected by the team of researchers from China Medical University and Hospital in Taiwan

Study participants were divided into two cohorts: all patients aged 20 years and older, who had been diagnosed with tuberculosis between 1998 and 2000, were classified in an exposed group, and all participants without tuberculosis history, formed the non-exposed group.

Any patients with cancer diagnosis were excluded from the study, to make sure that everyone was cancer-free at the start of both cohorts.

From the one million people, 716,872 adults were eligible for the analysis, out of which 4,480 were part of the tuberculosis cohort and 712,392 were in the non-tuberculosis cohort.

After following both groups from 2001 through 2007, the results showed that patients suffering from tuberculosis were 10.9 times more likely to develop lung cancer than non-tuberculosis patients – 26.3 versus 2.41 per 10,000 person-years.

The first group also had higher mortality rates than the non-tuberculosis patients, with 51.1 versus 8.2 per 10,000 person-years.

Dr. Chen added that “with the universal health insurance claims data of Taiwan, we identified 4,480 patients with tuberculosis from a group of 716,872 people and followed them for eight years or longer.

“The incidence of lung cancer in these tuberculosis patients was 11 times greater than people without tuberculosis.

“The risk of lung cancer may increase further to almost 16 times greater if patients with tuberculosis also suffer from chronic obstructive pulmonary disease.

“This study suggests that it is also important to watch out for lung cancer prevention in the campaign against tuberculosis.”

This new study was published in the January issue of the Journal of Thoracic Oncology.