[Thymoma with extensive coagulative necrosis and high serum level of CYFRA 21-1; report of a case].

A 73-year-old woman complained of right chest discomfort. Chest X-ray during the follow-up for rheumatoid arthritis showed a mediastinal tumor. Chest computed tomography (CT) and magnetic resonance imaging (MRI) showed a 65-mm tumor in the right anterior mediastinum. A blood test showed high serum levels of CYFRA 21-1(29.8 ng/ml), white blood cells( WBC 10,800/µl), and C-reactive protein(CRP 16.1 mg/dl). Subsequently, inflammatory reactions improved, and the thymic tumor was resected. Histopathologically, the tumor was a type B2 thymoma with extensive coagulative necrosis. After resection, the serum CYFRA 21-1 level returned to the normal range.