Clinical characteristics and outcomes of thymoma‐associated myasthenia gravis

Background and purpose Prognosis of myasthenia gravis (MG) in patients with thymoma is not well established. Moreover, it is not clear whether thymoma recurrence or unresectable lesions entail a worse prognosis of MG. Methods This multicenter study was based on data from a Spanish neurologist‐driven MG registry. All patients were aged >18 years at onset and had anti‐acetylcholine receptor antibodies. We compared the clinical data of thymomatous and nonthymomatous patients. Prognosis of patients with recurrent or nonresectable thymomas was assessed. Results We included 964 patients from 15 hospitals; 148 (15.4%) had thymoma‐associated MG. Median follow‐up time was 4.6 years. At onset, thymoma‐associated MG patients were younger (52.0 vs. 60.4 years, p