Extended transcervical thymectomy with partial upper sternotomy: results in non-thymomatous patients with myasthenia gravis

Abstract

Objectives: Thymectomy is a recognized treatment for myasthenia gravis (MG), but the optimal surgical approach is yet to be determined. This study analysed the results in non-thymomatous MG patients treated at our institution using an extended transcervical access with partial upper sternotomy (TC-US), in order to describe cumulative incidence of remission and its predictors.

Methods: In the period 1988-2012, 215 non-thymomatous MG patients underwent thymectomy using the TC-US approach. There were 61 males and 154 females (median age: 33 years). Primary end points were complete stable remission (CSR) and pharmacological remission (PR). Clinico-pathological predictors of CSR/PR were analysed including age, gender, preoperative MG symptom duration, preoperative immunosuppression therapy and disease severity.

Results: The median follow-up period was 127 months. The median preoperative duration of MG symptoms was 9 months (interquartile range 4-13). The median operative time was 65 min (range: 45-135). There was no postoperative death. Morbidity rate was 7% (14 patients, no major complication). Ten patients died at the follow-up (3 of MG). MG symptoms improved in 85% (150/176) of the patients. CSR rate was 34%, PR rate was 4%. Cumulative incidence of CSR/PR was 27, 37 and 46% at 5, 10 and 15 years, respectively. Independent predictors of increased CSR/PR rate were age (P = 0.028) and MG symptom duration <6 months (P = 0.013).

Conclusions: Our data suggest that in patients with non-thymomatous MG, thymectomy by TC-US has a remission rate not inferior to those reported after trans-sternal or video-assisted thoracic surgery techniques. The short duration of MG symptoms before thymectomy is a predictor of remission. The technique strikes a reasonable balance between the extent of thymic resection, operative and anaesthesia time, patient acceptance, neurological outcome and costs.

Keywords: Myasthenia gravis; Outcomes; Thymectomy; Thymus.