Robotic-Extended Rethymectomy for Refractory Myasthenia Gravis: A Case Series

Semin Thorac Cardiovasc Surg. 2020;32(3):593-602. doi: 10.1053/j.semtcvs.2019.10.016. Epub 2019 Nov 2.

Abstract

To assess the safety and efficacy of robotic-extended rethymectomy in selected refractory myasthenia gravis (MG) patients with suspected residual thymic tissue. Robotic-extended rethymectomy was performed in 6 MG patients with seropositive acetylcholine receptors (AChR) antibody who had undergone a previous thymectomy (1 cervicotomy, 2 video-assisted thoracoscopic surgeries, and 3 sternotomies). The median observation time before robotic rethymectomy was 108 (24-171) months. The main outcomes were perioperative morbidity, mortality, conversion to open surgery, and clinical outcomes according to the Myasthenia Gravis Foundation of America Post-Intervention Status (MGFA-PIS). Before rethymectomy, all patients required immunosuppressants and 5 patients (83.3%) required intravenous immune globulin and/or plasma exchange to control the symptoms. The median specimen weight was 24.5 (14-144) g after rethymectomy, and residual thymic tissue was found in 5 patients (83.3%). No conversion to open surgery or perioperative morbidity and mortality was observed. With a median follow-up time of 46.5 (13-155) months, 3 patients (50%) achieved "improved" and 3 (50%) were "unchanged" according to the MGFA-PIS. Compared with preoperative use, the median daily dose of corticosteroids statistically decreased (25 [7.5-60] vs 0 [0-5] mg, P = 0.002) without significant change in azathioprine use (100 [0-200] vs 50 [0-150] mg, P = 0.360). AChR antibody positive MG patients with a treatment refractory long-term course after thymectomy might have remaining thymic tissue with the 2 commonly associated thymus pathologies, thymoma, and follicular hyperplasia. Robotic-extended rethymectomy might be considered as a safe and beneficial treatment option in these patients.

Keywords: Clinical outcome; Refractory myasthenia gravis; Robotic-extended rethymectomy; Surgical decision making.

Publication types

  • Video-Audio Media

MeSH terms

  • Adolescent
  • Adrenal Cortex Hormones / therapeutic use
  • Adult
  • Autoantibodies / blood
  • Biomarkers / blood
  • Child
  • Female
  • Humans
  • Immunoglobulins, Intravenous / therapeutic use
  • Immunosuppressive Agents / therapeutic use
  • Male
  • Middle Aged
  • Myasthenia Gravis / blood
  • Myasthenia Gravis / diagnosis
  • Myasthenia Gravis / surgery*
  • Plasma Exchange
  • Receptors, Cholinergic / immunology
  • Reoperation
  • Retrospective Studies
  • Robotic Surgical Procedures* / adverse effects
  • Thymectomy / adverse effects
  • Thymectomy / methods*
  • Time Factors
  • Treatment Outcome

Substances

  • Adrenal Cortex Hormones
  • Autoantibodies
  • Biomarkers
  • Immunoglobulins, Intravenous
  • Immunosuppressive Agents
  • Receptors, Cholinergic