[Localized nodular pulmonary amyloidosis; report of a case].

A 66-year-old female was admitted to our hospital because of chest abnormal shadow. Chest X-ray and chest computed tomography (CT) on admission showed a nodule in the right middle lobe. The nodule was not diagnosed preoperatively by a bronchoscopy. She underwent partial lung resection including the nodule with video-assisted thoracoscopic surgery. The pathological diagnosis was amyloidosis, and we diagnosed her illness as localized nodular pulmonary amyloidosis, since the amyloid substance was type AL. In addition, electron microscopy showed amyloid as straightly fibrous materials in alveolus. It is difficult to differentiate amyloidosis from lung cancer by radiology, and the lung biopsy with video-assisted thoracoscopic surgery is useful and a safety way to establish diagnosis.