Lepidic Pulmonary Metastasis from Pancreatic Carcinoma Mimicking Organizing Pneumonia, Diagnosed by a Transbronchial Cryobiopsy

A 78-year-old man with a history of pancreatic carcinoma underwent chest computed tomography (CT), which revealed a slowly enlarging consolidation in the right lower lobe. Forceps and percutaneous CT-guided lung biopsies showed no evidence of malignancy; therefore, organizing pneumonia was suspected. However, the patient's serum carbohydrate antigen 19-9 levels increased monthly, raising concerns about malignant lesions. A transbronchial cryobiopsy (TBCB) was performed to confirm the diagnosis of pulmonary metastasis of the pancreatic carcinoma. Pulmonary metastasis is an important differential diagnosis when chest CT shows consolidation, mimicking organized pneumonia. In addition, a TBCB can be a useful diagnostic tool for detecting lepidic growth patterns.