A case of CA19-9 producing Thymoma

Abstract

We describe a case of CA 19-9 producing thymoma. A 60-year-old man was admitted to our hospital because of an anterior mediastinal mass on computerized tomography (CT). Laboratory data showed an elevated serum CA 19-9 level of 116.7 U/ml. We suspected thymoma and thymo-thymectomy was performed. The pathological diagnosis of the tumor was Type B2 thymoma in the WHO classification and also non-invasive thymoma with Masaoka stage I. Immunohistochemical study demonstrated that some tumor cells stained positively for CA 19-9. No significant lesions were detected in the liver, gall-bladder, pancreas or gastrointestinal tract. The CA 19-9 level was normalized on the 15th postoperative day. Serum CA 19-9 may be a useful diagnostic parameter and follow-up marker in some patients with thymoma.