Comparative Clinical Outcomes of Thymectomy for Myasthenia Gravis Performed by Extended Transsternal and Minimally Invasive Approaches

Background. Both transsternal and video-assisted thoracoscopic surgery (VATS) approaches are used for thymectomy in myasthenia gravis. We compared outcomes of simultaneous experiences in two institutions: one utilizing the transsternal approach exclusively, the other using VATS procedures for all patients. The Myasthenia Gravis Foundation of America guidelines were used to standardize reporting. Methods. Between March 1992 and September 2006, 95 thymectomies were performed for myasthenia gravis; 48 by VATS and 47 by transsternal approach. Preoperative classification and postoperative disease status were compared between the groups. Results. Mean age was 39.8 +/- 14.9 (VATS) versus 34.4 +/- 13.2 years (transsternal) (p = 0.07); the proportion of females was 52% versus 67% (p = 0.15); and preoperative duration of myasthenia gravis was 27 +/- 44 versus 20 +/- 45 months (p = 0.43), respectively. Clinical follow up was 89.5% complete at a mean of 6.0 +/- 4.0 years and 4.3 +/- 2.9 years (p = 0.03). The operative time was 128 +/- 34 minutes (VATS) versus 119 +/- 27 minutes (transsternal) (p = 0.22). The need for postoperative ventilation was 4.2% versus 16.2% (p = 0.07) and mean length of stay was 1.9 +/- 2.6 versus 4.6 +/- 4.2 days (p < 0.001). Thymomas were found in 8.3% of VATS versus 13.3% of transsternal patients (p = 0.44). No myasthenia gravis related deaths occurred and 95.8% of the VATS and 97.9% of the transsternal patients were in either complete stable remission, pharmacologic remission, or minimal manifestations status. In the VATS group, 13 of 17 (76.5%) patients stopped prednisone usage after surgery versus 5 of 14 (35.7%) in the transsternal group (p = 0.022). Conclusions. Thymectomy is an effective treatment in patients with myasthenia gravis with equivalent clinical outcomes obtained by either approach.