Between July 1989 to February 1994 eight patients with thymoma were operated in the First surgical Clinic of University of Catania; in seven the neoplasia was associated with myasthenia gravis, the severity of which was evaluated according to the Osserman's classification. The surgical treatment has been: total thymectomy in four patients, in two total and partial resection was carried out respectively, and in two a macrobiopsy was performed. The postoperative staging was carried out according to Masaoka. The neoadjuvant chemotherapy and postoperative radiation therapy have been analyzed. The authors concluded that a rigorous anatomo-surgical and histopathological classification is the best way for the right use of postoperative adjuvant therapies to reduce the incidence of local and distant recurrence of these tumors.