Efficacy and safety of thoracoscopic thymectomy in the treatment of juvenile myasthenia gravis

Abstract

Background

Thymectomy is a well-established treatment for generalized myasthenia gravis in adults, but predictors of long-term efficacy and the optimum timing for intervention in juvenile myasthenia remain controversial.

Purpose

To review the preoperative presentation, surgical experience, and long-term neuromuscular follow-up in patients undergoing thoracoscopic thymectomy in a single institution.

Methods

A retrospective chart review of all patients undergoing thoracoscopic thymectomy for myasthenia gravis at a tertiary referral center between 2000 and 2010 and compared to an historical cohort of trans-sternal thymectomies performed between 1970 and 1995. Age at diagnosis, presurgical medications and hospitalizations, preoperative chest imaging, presence of acetylcholinesterase antibodies, Osserman Stage, time to operative intervention, length of follow-up, DeFillipi remission scale, as well as operative and post-operative data (length of surgery, blood loss, need for chest tube, length of intubation, length of hospital stay, pathology, and complications) were recorded.

Results

Fifteen patients undergoing thoracoscopic thymectomy were identified with a mean age of 11.3 years at time of diagnosis and average treatment duration of 12.5 months prior to operative intervention. Of these patients, most presented with Osserman Stage IIB (8) or III (5) disease. Two patients presented with Osserman Stage IIa disease. There were no reported complications, no conversions to an open approach, and an average length of stay of 2.6 days. Average length of follow-up was 37.5 months, available on 13 of 15 patients. Nine of 13 (69 %) were improved (DeFillippi Class 2 or 3) at 1-month follow-up, however, the pattern of remission waxed and waned, with only 50 % reporting improvement at 1 year, 86 % at 2 years and 75 % at 3 years. Only one patient was totally off medication. No patients required postoperative hospitalization for respiratory crisis.

Conclusions

Thoracoscopic thymectomy offers a safe approach to thymic resection in children with JMG with little associated morbidity and a short hospital stay, but should not be considered curative. Rather it appears to make generalized JMG more amenable to long-term medical management.