Heterogeneity of latent tuberculosis infection in a patient with lung cancer.

Latent tuberculosis infection may become a source of tuberculosis dissemination, even in a subclinical case, which have no abnormalities in the pulmonary parenchyma based on imaging studies. In this case, we presented tiny granulomas beside squamous cell carcinoma in a woman positive for interferon-γ release assay (IGRA). She had no symptoms or abnormalities in the parenchyma, except for the primary lesion. Mycobacterium tuberculosis was cultured from the mediastinal lymph nodes in concurrence with [F] fluoro-deoxy glucose uptake. The findings of the present study stress the need for careful attention to the development of tuberculosis in case of a positive IGRA.