Efficiency of ectopic thymectomy by three surgical approaches in non-thymomatous myasthenia gravis.

Background: To explore the efficiency of ectopic thymectomy by the three surgical approaches of trans-sternum, right unilateral thoracoscopy and thoracoscopic subxiphoid in patients with non-thymomatous myasthenia gravis.

Methods: 155 consecutive non-thymomatous myasthenia gravis patients who underwent extended thymectomy by 3 approaches including trans-sternum, right unilateral thoracoscopy and thoracoscopic subxiphoid in 1st affiliated hospital of Sun Yat-Sen University from January 2017 to October 2019 were reviewed. Differences of perioperative clinical characteristics in three surgical approaches were analyzed.

Results: Time to onset of myasthenia gravis (early or late) (p = 0.018), blood loss (p < 0.001), duration of operation (p = 0.031), duration and volume of thoracic drainage (p = 0.039 and p = 0.026), length of hospitalization (p = 0.039), the efficiency of ectopic thymectomy (p = 0.037), and the detection rate of ectopic thymus in the second quadrant (p = 0.018) were different among the three surgical approaches. In univariate logistic regression analysis, higher efficiency of ectopic thymectomy were associated with transsternal (OR 2.36, 95% CI 1.32-4.22, p = 0.011) and thoracoscopic subxiphoid approaches (OR 2.07, 95% CI 1.12-3.82, p = 0.033). In the multiple logistic regression analysis, the transsternal approach (OR 2.02, 95% CI 1.10-3.71, p = 0.024) was an independent protective factor for the efficiency of ectopic thymectomy.

Conclusions: Both the right unilateral thoracoscopic and thoracoscopic subxiphoid approaches have advantages over the transsternal approach in short-term postoperative recovery. Transsternal approach is still the best choice for ectopic thymectomy while thoracoscopic subxiphoid approach show the potential as an alternative way.