Robotic-assisted thoracic surgery reduces perioperative complications and achieves a similar long-term survival profile as posterolateral thoracotomy in clinical N2 stage non-small cell lung cancer patients: a multicenter, randomized, controlled trial

Background: Our previous study demonstrated the safety and short-term efficacy of robotic-assisted thoracic surgery (RATS) in clinical N2 (c-N2) stage non-small cell lung cancer (NSCLC) patients. From this, the present study was devised, in which the follow-up time and sample size were both extended to explore the long-term efficacy and potential benefit in survival of RATS compared with lobectomy in c-N2 stage NSCLC patients. Methods: Patients with c-N2 NSCLS were randomly assigned in a 1:1 ratio to accept operation through thoracotomy or RATS. The da Vinci Surgical System (Si/Xi) was applied in the RATS group, while conventional lobectomy with a rib-spreading incision was applied in the posterolateral thoracotomy group. Primary endpoint was defined as disease free survival and overall survival (OS) of all recruited patients. Results: Compared with posterolateral thoracotomy group (N=72), the RATS group (N=76) had a reduced blood loss (P<0.001), decreased drainage duration (P=0.002), and decreased postoperative pain visual analog score (all P<0.001), but increased overall cost (P<0.001). Meanwhile, no difference in the other postoperative complications (such as air leakage, subcutaneous emphysema, atrial fibrillation etc.) was found between the RATS group and the posterolateral thoracotomy group (all P>0.05). Regarding long-term outcome, no difference in disease-free survival (DFS; P=0.925) or OS (P=0.853) was observed between the RATS group and posterolateral thoracotomy group. Subgroup analyses and multivariable Cox regression analyses also found no difference in DFS or OS between the RATS group and posterolateral thoracotomy groups. Conclusions: RATS reduced intraoperative bleeding, drainage duration, postoperative pain, and achieved similar long-term survival outcomes compared with posterolateral thoracotomy in c-N2 stage NSCLC patients.