Submitted by: Rocio Carolina Garcia Santibanez, MD
Edited by: Clark W. Pinyan, MD, MPH
Wolfe G, Kaminski H, Aban I, Minisman G, Kuo H, Marx A, et al. Long-term effect of thymectomy plus prednisone versus prednisone alone in patients with non-thymomatous myasthenia gravis: 2-year extension of the MGTX randomised trial. The Lancet Neurology
. January 25, 2019.
Authors report a 2 year extension of the landmark MGTX trial published in 2016. The objective was to evaluate long term effects of thymectomy in non-thymomatous myasthenia gravis for up to 5 years. Enrolled patients had a diagnosis of generalized myasthenia, aged 18-65 with disease duration of less than 5 years, positive AchR antibodies and no evidence of thymoma. Patients were randomized to trans-sternal thymectomy and prednisone or prednisone only. Of the 111 patients in the initial trial, 68 continued in the extension trial but 50 completed it (33 in the prednisone group and 26 in thymectomy plus prednisone group). As seen in the initial trial, the thymectomy plus prednisone group had lower QMG (quantitative myasthenia gravis) score and lower average alternate day prednisone dose (24mg vs 48mg). Hospitalization for MG exacerbation was more common in the prednisone only group.
Though this is a smaller cohort than the original study, it appears that thymectomy continues to provide benefits up to year 5 in non-thymomatous generalized myasthenia gravis.