[Thymoma. A retrospective study]

We review cases of thymic cell tumor treated between January 1991 and March 1998. Nineteen of the 23 cases studied involved thymoma. Eight (42%) were asymptomatic, 4 (21%) were associated with myasthenia gravis and 7 (37%) were symptomatic. The most common symptom was non-specific chest pain, reported by 4 (47%) patients with symptoms. Classifying the cases of thymoma by Masaoka's system, we found that 12 were cases of thymoma in stage I (63.2%), 4 in stage II (21.1%) and 3 in stage III (15.8%). No stage IV patients were treated. Treatment consisted of full exeresis of the tumor in 17 (89.5%) cases, partial resection in one case (5.2%) and biopsy of the tumor in one non-resectable, case. Adjuvant radiotherapy was applied in seven cases. Chemotherapy was not prescribed. With follow-up ranging from 9 to 96 months, half the patients survived 21 months after surgery. Among the surviving patients, mortality was nil at the end of the study. The results of microscopic, cytologic and blood analyses were of scarce value in differentiating between benign and malignant tumors, even though p53 and bcl2 antigen positivity and clinical stage have been related to poor prognosis in recent years.