[A case of malignant thymoma associated with myasthenia gravis, pure red cell aplasia and high serum level of SCC antigen].

We present a case of 43-year-old man with pure red cell aplasia appearing 8 years after thymothymectomy. He underwent an operation and postoperative radiotherapy for malignant thymoma associated with myasthenia gravis in 1983. In 1991 high serum level of SCC antigen was noted and a metastatic tumor was found in the retroperitoneal region. After removal of the tumor pure red cell aplasia developed, which responded to steroid therapy. The serum level of SCC antigen is still abnormally high.