Myasthenia gravis and invasive thymoma. A 20-year experience.

Over the last 20 years, 15 patients with myasthenia gravis and invasive thymoma have been treated in our department. Eight of these patients underwent either nontotal excision or were not operated on due to massive invasion, while 7 underwent total excision. These 15 cases represent 6.2% of the 242 myasthenic patients treated during this period. Six of the 8 nontotal excision cases died, and 2 of the 7 total excision cases succumbed. The prognosis of total excision cases was better than that of nontotal excision cases. The overall 5-year survival rate was 73%, and the 10-year survival rate 20%. Total excision of the thymoma, if possible, and high doses of corticosteroids and combination chemotherapy for the remaining tumor seem to be the treatments of choice.