Small samples, big problems: lipoid pneumonia mimicking lung adenocarcinoma

Lepidic adenocarcinoma of the lung is a distinct form of lung cancer, characterized by proliferation of neoplastic cells along the alveolar lining without changes in the structure of the alveoli. It is a variant of pulmonary adenocarcinoma, the most common type of lung cancer, and generally has a better prognosis than do other forms of lung cancer, because of its slow growth and more limited pattern of spread. Sampling of small fragments of lung tissue (e.g., transbronchial biopsy) remains a commonly used diagnostic tool for lung cancer. The main limitations are as follows: 1) samples might not be representative of the entire lesion; and 2) crush artifacts that might not provide enough tissue for a comprehensive histopathological examination, including immunohistochemistry and molecular testing. This can lead to erroneous diagnostic conclusions and unnecessary treatments. (author)