[Thymoma with Pure Red Cell Aplasia;Report of a Case].

A thymoma with pure red cell aplasia (PRCA) is relatively rare. A 71-year-old woman complainted of dizziness and her blood cell count showed a severe anemia. She was diagnosed as PRCA by bone marrow aspiration biopsy, which showed marked decrease in number of erythroblasts. In addition, the chest computed tomography revealed a solid tumor in the anterior mediastinum. She underwent extended thymothymectomy through median sternotomy. The resected specimen was 10.5×9.7 cm in diameter. The pathological diagnosis was type AB thymoma of the World Health Organization classification, and Masaoka stage I. Ciclosporin was started to treat PRCA 3 months after the surgery, and she has been well for about 1 year after surgery without recurrence of thymoma or relapse of anemia.