Abstract
A case of a 39-year-old man, whose chest computed tomography (CT) during a health examination, pointed to a nodule with calcification in the left upper lobe. After 6 months, the nodule was diagnosed as an inflammatory nodule because the size of the nodule had not changed. After 4 years from the initial health examination, a positron emission tomography (PET-CT), showed that the nodule was enlarged and he was admitted in our department of surgery because lung cancer was suspected. Partial lung resection which included the calcificated nodule was performed in video assisted thoracoscopic surgery, and the resected specimen was examined pathologically. There were no malignant findings. The final pathological diagnosis was dendriform pulmonary ossification, because there were bone trabeculae with bone marrow in the lung interstitium.
