68-year-old man had mantle cell lymphoma under chemotherapy treatment. He was admitted to hospital due to fever and respiratory failure. Chest X-ray and HRCT were taken (Figure 1
A and 1
B). Because the diagnosis of bilateral lung infiltration remained uncertain after initial evaluation, the patient underwent Video-assisted thoracoscopic lung biopsy. The biopsy result revealed diffuse alveolar damage, hyaline membranes lining the alveolar surfaces (Hematoxylin and Eosin stain, 200X) (Figure 1
C). The possibility of involvement by the previously diagnosed mantle cell lymphoma was excluded.