Double sternal elevation subxiphoid versus uniportal thoracoscopic thymectomy associated with superior clearance for stage I-II thymic epithelial tumors: Subxiphoid thymectomy compared with VATS

Abstract

Objective: This study aimed to evaluate the therapeutic efficacy of thymectomy through a subxiphoid video-thoracoscopic approach with double elevation of the sternum compared with traditional intercostal uniportal video-assisted thoracic surgery for stage I-II thymic epithelial tumors (using the Masaoka-Koga staging system).

Method: Patients with thymic tumors underwent resection through intercostal video-assisted thoracic surgery or subxiphoid video-thoracoscopic approach. Only those with pathologically confirmed thymic epithelial tumors were enrolled. Perioperative short-term/long-term outcomes were compared between 2 groups after propensity-score matching.

Results: A total of 141 patients diagnosed with thymic epithelial tumors and scheduled for minimally invasive surgery were included. In the intercostal video-assisted thoracic surgery group, the prevalence for conversion to open surgery was higher than in the subxiphoid video-thoracoscopic approach group for stage III thymic tumors (P = .019). After propensity-score matching for 122 patients undergoing video-assisted thoracic surgery, significantly larger resected specimens were found in the subxiphoid video-thoracoscopic approach group compared to the intercostal video-assisted thoracic surgery group (11.7 ± 3.8 vs 7.1 ± 2.7 cm, P < .001). The pain score on the first postoperative day (1.6 ± 0.6 vs 2.0 ± 0.7, P = .011) and the day of hospital discharge (1.2 ± 0.7 vs 1.6 ± 0.6, P = .017) in the subxiphoid video-thoracoscopic approach group were significantly lower. The operation time (168.4 ± 59.3 vs 92.5 ± 46.0 min, P < .001), chest tube drainage time (3.6 ± 1.2 vs 2.9 ± 0.9 days, P = .001), and hospital stay (3.7 ± 1.3 vs 2.9 ± 0.9 days, P = .004) were longer in the subxiphoid video-thoracoscopic approach group, with higher intraoperative blood loss (69.3 ± 61.0 vs 45.6 ± 42.5 mL, P = .045). No significant differences were found in the hospitalization cost, incidence of complications, or 3-year disease-free survival (96% vs 92%, P = .473) between the 2 groups. Four patients with stage III disease in the subxiphoid video-thoracoscopic approach group reached a 3-year disease-free survival of 75%.

Conclusion: The subxiphoid video-thoracoscopic approach with double elevation of the sternum shows the potential for more extensive clearance of thymic tissue for thymic epithelial tumors compared to intercostal video-assisted thoracic surgery. Its inferior operation time and blood loss could be a trade-off for improved pain control and equivalent hospitalization cost, complications, and 3-year disease-free survival. The subxiphoid video-thoracoscopic approach may offer an advantage treatment for early-stage thymic epithelial tumors and may also be suitable for unexpected advanced thymic tumors identified intraoperatively.