[Synchronous Thymic Carcinoma and Primary Lung Cancer]

A 79-year-old woman visited a local doctor with a chief complaint of cough. A computed tomography (CT) scan revealed an anterior mediastinal tumor and 20 mm sized ground-glass nodule (GGN) in the right upper lobe. Bronchoscopy was performed, but no definitive diagnosis was made for GGN and follow-up observation was made with an image. The anterior mediastinal tumor was a solid tumor of 50 mm in size, and invasive thymoma was suspected. A total thymectomy with pericardial partial resection was performed through a median sternotomy. Histopathological diagnosis was squamous cell carcinoma, and no pericardial infiltration was observed. On the other hand, GGN of the right upper lobe during follow-up increased in size and thoracoscopic surgery was performed 3 months after surgery for thymic carcinoma. Adenocarcinoma was diagnosed by rapid diagnosis and the upper lobectomy with lymph node dissection were conducted. No signs of recurrence have been observed for 5 years after operation.