A 60-year-old man presented to our department for investigation of pulmonary opacity detected by Chest Computed Tomography (CT) at medical checkup. He had no clinical symptoms. Chest CT revealed a non-specific infiltrate with linear shadow in right upper lobe (Fig. 1: panel A), regarded as an old inflammatory change, and carefully observed. However, the shadow became larger, and, new lesions appeared in other lobes. All substances the could cause pneumonia were avoided at that time. However, the infiltrate persisted and became larger, and abnormal uptake of FDG was found at three months after avoiding ongoing exposure (Fig.
