Abstract
We report a case of pulmonary nontuberculous mycobacterial disease with abnormal 18F-fluorodeoxyglucose (18FDG) accumulation and an elevated serum CA19-9 level. A 61-year-old woman showed an elevated serum CA19-9 (299.7 U/ml) level during follow-up after surgery and chemotherapy for a uterine sarcoma (leiomyosarcoma) and its pulmonary metastasis. Chest CT revealed a solitary mass shadow measuring 30 × 44 mm in the remaining left lower lobe. Whole-body 18FDG-positron emission tomography (PET) showed abnormal accumulation in the left pulmonary mass (maximum standardized uptake value (SUV) = 4.5). These data suggested recurrent pulmonary metastasis. Partial pulmonary resection was performed. Pathological findings of the resected specimen were aggregated epithelioid granulomas with multinucleated giant cells including partial caseous necrosis. There were acid-fast-positive bacilli around the caseous necrosis. Bacterial culture of the resected tissue revealed Mycobacterium avium. The pulmonary mass was diagnosed as pulmonary nontuberculous mycobacterial disease. The postoperative serum CA19-9 value returned to normal. There were many bronchoepithelial cells positive for CA19-9 immunostaining in the resected specimen.