What is efficacy of thymectomy in the treatment of myasthenia gravis (MG)?

Updated: Aug 27, 2018
  • Author: Abbas A Jowkar, MBBS; Chief Editor: Nicholas Lorenzo, MD, CPE, MHCM, FAAPL  more...
  • Print

Trans-sternal thymectomy has been known to improve MG in many anecdotal case reports and has been adopted as an effective way to manage the disease and even induce remission or lessen the requirements or perhaps remove the need of prednisone and other immunosuppressants.

Randomized Trial of Thymectomy in Myasthenia Gravis is a landmark study. This is the first randomized trial of thymectomy in MG. The cohort of patients who were involved in the trial had generalized MG and were acetylcholine receptor antibody positive. Patients who entered the study were between the ages of 18 and 65 years, and none could have a duration of MG based on their historical presentations that exceeded 5 years. Patients were randomized one to one to thymectomy plus prednisone or to prednisone alone. They could go on prednisone as long as they did not exceed a dosage of 50 mg a day. Other immunosuppressants were excluded. The intervention was an extended trans-sternal thymectomy in order to get as much thymic tissue as possible. The primary outcome was tiered and included both outcomes of the disease based on QMG score and prednisone dose. The outcome was that not only was the prednisone requirement less in the thymectomy group, but there was a better outcome in patients who underwent thymectomy. Also, the requirement of azathioprine was reduced in the thymectomy patients. Therefore, over a period of 3 years, thymectomy was associated with more favorable clinical outcomes with respect to requirements for prednisone and azathioprine therapy, the number of symptoms and the distress level related to immunosuppressive agents, and the need for hospitalization to manage disease exacerbations. [60]

An upper age limit for extended transternal thymectomy is not determined. Patients with an upper age limit of 65 years without significant medical comorbid conditions can be considered for thymectomy.

Phrenic nerve injury resulting in diaphragmatic paralysis and paresis of recurrent laryngeal nerve were some known complications.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!