Adenocarcinoma of the lung mimicking interstitial lung disease

Although benign reactive conditions can be misinterpreted as malignancies, a number of malignant lesions can in turn be mistaken for interstitial lung disease. A nonsmoking male aged 66 years who presented with multifocal dispersed, parenchymal and subpleural nodules, most of them cavitated or pseudocavitated, and that radiologically mimicked non-malignant conditions, such as pulmonary Langerhans cell histiocytosis or peribronchiolar organising pneumonia with bronchiectasis on computed tomography scan, was hospitalised. Microbiological and immunological tests were negative. Since sufficient tissue could not be obtained via bronchoscopy, the patient was scheduled for video-assisted thoracic surgery. The final diagnosis revealed invasive adenocarcinoma with a predominant lepidic pattern.