Surgical approaches for stage Ⅰ and Ⅱ thymoma-associated myasthenia gravis:feasibility of complete video-assisted thoracoscopic surgery (VATS) thymectomy in comparison with trans-sternal resection

Complete resection could be achieved in virtually all myasthenic patients with Masaoka stage Ⅰ and Ⅱ thymoma using the trans-sternal technique.Whether this is appropriate for minimally invasive approach is not yet clear.We evaluated the feasibility of complete video-assisted thoracoscopic surgery (VATS) thymectomy for the treatment of Masaoka stage Ⅰ and Ⅱ thymoma-associated myasthenia gravis,compared to conventional trans-sternal thymectomy.We summarized 33 patients with Masaoka stage Ⅰ and Ⅱ thymoma-associated myasthenia gravis between April 2006 and September 2011.Of these,15 patients underwent right-sided complete VATS (the VATS group) by using adjuvant pneuomomediastinum,comparing with 18 patients using the trans-sternal approach (the T3b group).No intraoperative death was found and no VATS case required conversion to median sternotomy.Significant differences between the two groups regarding duration of surgery and volume of intraoperative blood loss (P=0.001 and P < 0.001,respectively) were observed.Postoperative morbidities were 26.7% and 33.3% for the VATS and T3b groups,respectively.All 33 patients were followed up for 12 to 61 months in the study.The cumulative probabilities of reaching complete stable remission and effective rate were 26.7% (4/15) and 93.3% (14/15) in the VATS group,which had a significantly higher complete stable remission and effective rate than those in the T3b group (P=0.026 and P=0.000,respectively).We conclude that VATS thymectomy utilizing adjuvant pneuomomediastinum for the treatment of stage Ⅰ and Ⅱ thymoma-associated myasthenia gravis is technically feasible but deserves further investigation in a large series with long-term follow-up.