Robotic extended re-thymectomy for refractory myasthenia gravis: a case series

Background:

Refractory myasthenia gravis (MG) is frequently defined as failure to respond to adequate immunosuppressive treatments and/or thymectomy. Re-thymectomy is a treatment option in patients with refractory MG. This study aimed to assess the safety and efficacy of robotic extended re-thymectomy in patients with refractory MG.

Material and method:

Robotic extended re-thymectomy was performed in six patients with MG who had undergone a previous thymectomy (one cervicotomy, two video assisted thoracoscopic surgery [VATS] and three sternotomy). After a median follow-up time of 108 (24 – 171) months, all patients required immunosuppressant and five (83.3%) patients required intravenous immune globulin and/or plasma exchange to control the symptoms before re-operation. Clinical outcomes were assessed according to the Myasthenia Gravis Foundation of America Post-Intervention Status (MGFA-PIS).

Result:

No perioperative morbidity and mortality as well as conversion to open was observed in our series. The median weight of specimen was 24.5 (14 – 144)g after re-thymectomy and residual thymic tissue was found in five (83.3%) patients. After excluding one patient who lost to the last follow-up, three patients (60%) achieved “improved” and two (40%) achieved “unchanged” with a median follow-up time of 61 (13 – 155) months. Compared with preoperative use, the median daily dose of corticosteroids decreased significantly (30 [7.5 – 60] VS 0 [0 – 5] mg, p= 0.008) without significant change in cholinesterase inhibitors use (450 [240 – 600] VS 240 [150 – 480] mg, p= 0.172) and azathioprine use (100 [50 – 200] VS 100 [0 – 150] mg, p= 0.331).

Conclusion:

Robotic extended re-thymectomy seems to be effective in patients with refractory MG in terms of improving symptoms and reducing corticosteroids requirement.