Robotic subxiphoid thymectomy versus lateral thymectomy: a propensity score-matched comparison

Abstract OBJECTIVES This study aims to compare the surgical outcomes between conventional robotic lateral thymectomy and recently introduced robotic subxiphoid thymectomy (RXT) for the surgical treatment of anterior mediastinal tumours. METHODS Between May 2008 and July 2020, the patients who underwent robotic thymectomy were included in the study. Because RXT was more frequently performed in the tumours with advanced stages and located in the upper mediastinum abutting the brachiocephalic vein, we conducted propensity score matching to minimize selection bias. RESULTS A total of 389 patients (subxiphoid and lateral thymectomy in 188 and 200 patients, respectively) underwent robotic thymectomy, and 141 matched pairs in each group were included in the analysis. After the matching process, both methods showed comparable demographic features, pathological diagnoses and pathologic stages. RXT was performed more frequently for mediastinal masses abutting the brachiocephalic vein (P < 0.01). The proportion of simultaneous resection of adjacent structures, including the lung, pericardium and phrenic nerve, was similar between the 2 groups; however, the proportion of brachiocephalic vein resection was significantly higher in the RXT (P < 0.01). Although both groups showed comparable complication rates (P = 0.80), RXT was associated with shorter hospital stays [2.4 (2.4) vs 3.1 (2.4) days; P = 0.03] and a lower pain score in the immediate and early postoperative periods. CONCLUSIONS RXT could be performed safely in complex upper mediastinal tumours abutting the brachiocephalic vein and showed better early outcomes with shorter hospital stays and lesser postoperative pain than robotic lateral thymectomy.