Masaoka stage I type A thymomas rarely recur. We report the case of an 82-year-old man who developed endobronchial metastasis after thymothymectomy for Masaoka stage I type A thymoma. Twenty years after surgery, the patient developed bloody sputum, and chest computed tomography revealed a neoplasm obstructing the right upper lobe bronchus of the lung with enlarged mediastinal lymph nodes. He underwent right upper lobectomy and mediastinal lymph node dissection. Although preoperative pathological diagnosis was squamous cell carcinoma of the lung, postoperative histopathology revealed endobronchial metastasis of the thymoma. Nine years later, at age 89, the patient is alive and well.
Keywords: bloody sputum; endobronchial metastasis; type A thymoma.