Active tuberculosis is an important complication in Japanese lung cancer patients. We studied the generation-wise trend of latent tuberculosis infection (LTBI) among lung cancer patients. We analyzed background data including birth year, lung cancer status, and interferon-gamma release assay (IGRA) data of lung cancer patients who were admitted to National Hospital Organization Tokyo National Hospital from 2010 to 2016. Of the 1450 cases, 7 showed active tuberculosis and 45 had previous tuberculosis. Of the remaining 1398 patients, 795 underwent IGRAs and 120 (15%) of them were found to have LTBI. Patients with LTBI were older (p = 0.0005), and the proportion of smokers was also higher in this group (p = 0.0159) than among those without LTBI. LTBI incidence decreased from 33% among patients born in the 1920s to 21%, 15%, 9.8%, and 5.1% among those born in the 1930s, 1940s, 1950s, and after 1960, respectively. A significant decrease in the smoking adjusted risk ratio was also observed with every generation (p < 0.0001). Our study suggests that the total number of patients with active tuberculosis comorbid with lung cancer will greatly decrease in the future in Japan. However, owing to recent improvements in lung cancer prognosis due to advances in cancer medication, careful monitoring for active tuberculosis development may be required in lung cancer patients with LTBI.
Keywords: Comorbidity; Latent tuberculosis infection; Lung cancer.
Copyright © 2019 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.