[Four cases of thymoma associated with pure red cell aplasia]

Thymomas associated with pure red cell aplasia (PRCA) constituted only 3.3% of 122 thymomas treated in our department from 1963 to March, 1995. Four patients with this disease (2 men and 2 women, mean age: 58 years, range: 41 to 66 years old) are reported. Auto-antibodies were found in all 4 cases, increase of T cell in two, suppression of erythropoietin production in one, and antibody to EB virus in one. Operation was performed in all cases (two thymothymectomies, one extended thymothymectomy, and one thymomectomy), and 3 of 4 patients were in the progressive stage of Masaoka's classification (I, III, IVa, and IVb each). As for the pathological findings, mixed type was found in three cases and lymphocyte predominant type in one. Two patients died from radiation pneumonia. As for PRCA, postoperative therapy was effective (100%) in all patients.