Thymectomy in Myasthenia gravis

Over recent years, investigations into the pathophysiology of myasthenia gravis (MG) have made great progress, resulting in characterization of subgroups, and extension of multimodal treatment approaches. This applies especially to the role of thymectomy (Thx). For thymoma-associated MG, Thx is always indicated. Furthermore, based on large cohort studies over decades, Thx has also become a central part of immune-modulating therapy in MG patients without thymoma. The lack of randomized studies, however, caused persistent uncertainty regarding the significance of Thx. The MGTX study has clearly shown the effectiveness of Thx. Particularly in the acquired early onset MG (EOMG), complete resection of all thymic tissue resulted in significant improvement in myasthenic complaints and reduction in immunosuppressive medication. Because the MGTX study only included patients younger than 65 years with generalized MG who were positive for acetylcholine-receptor antibodies, at present the significance of Thx for other relevant subgroups such as those with juvenile MG or ocular MG, older MG patients, as well as seronegative patients is under investigation. Even the prevailing opinion of no benefit of Thx for MuSK-positive patients probably needs reevaluation because of equivocal findings. With respect to surgery, the value of thoracoscopic modifications for Thx as a minimally-invasive alternative to extended median sternotomy for MG employed in the MGTX study is currently being evaluated. For clinical-scientific reasons, randomized comparative studies would be required for further assessment of different minimally-invasive Thx-techniques as compared to the conventional open procedures. Currently, however, robot-assisted thoracoscopic unilateral approach for Thx by an experienced surgeon meets all requirements related to surgical, clinical-neurological, and patient-related aspects. Ethical aspects, therefore, will become more important with regard to the comparison of different operation techniques.