[The Significance of Extended Thymectomy in Non-Thymomatous Myasthenia Gravis: an MGTX Study].

In August 2016, the results of the international randomized, controlled, trial that studied the safety and efficacy of extended trans-sternal thymectomy (ETTX) for patients with non-thymomatous myasthenia gravis (MG) was published. The inclusion criteria for this study were: 1) male and female subjects aged>18.0 and <60.0 years with non-thymomatous MG; 2) MG Foundation of America (MGFA) Clinical Classification Class II-IV at entry; 3) anti-acetylcholine receptor antibody (AChRAb) positive; and 4) receiving optimal oral anticholinesterase treatment with or without oral prednisone. Subjects were randomized to one of two protocols: prednisone alone or extended transsternal thymectomy (ETTX) plus prednisone. A total of 126 patients were randomized. The ETTX plus prednisone protocol improved the quantitative MG scores, decreased the total amount of prednisone, and decreased symptoms and side effects, resulting in a better quality of life compared with the prednisolone alone protocol. These results have required us to change our standard therapeutic protocol for MG. In addition, the safety and efficacy of ETTX with thymectomy via robotic methods needs to be considered. The MGTX study did not address the efficacy and safety of ETTX for younger or older patients, for MGFA Clinical Classification Class I or V patients, or for AChRAb-negative patients.