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

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.

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.

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.

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.