Introduction: Although thymoma is the most common anterior mediastinal tumor, only 5% of thymoma cases develop pure red cell aplasia (PRCA).

Case Presentation: In this article we have reported a 59-year-old man with a large anterior mediastinal mass (diameter of 10 cm) and severe anemia, that thymoma and pure red cell aplasia have been demonstrated by histopathologic and hematological examination. Despite the large mass, a complete video-assisted thoracoscopic surgery (VATS) thymectomy and combinational medical therapy were performed for him successfully. Aplasia remission occurred 6 months after thymectomy and his hemoglobin level reached to 13 g/dL.

Conclusions: We believe that a complete resection in combination with medical therapy is necessary to achieve total remission of PRCA symptoms and conclude that VATS thymectomy is an effective and technically feasible procedure for surgery without any contraindications about the size of the thymoma in these patients.