Robot-assisted Versus Conventional Minimally Invasive Esophagectomy for Resectable Esophageal Squamous Cell Carcinoma: Early Results of a Multicenter Randomized Controlled Trial: the RAMIE Trial

Objective: To compare perioperative and long-term outcomes of robot-assisted minimally invasive esophagectomy (RAMIE) and conventional minimally invasive esophagectomy (MIE) in the treatment for patients with esophageal squamous cell carcinoma (ESCC).

Summary background data: RAMIE has emerged as an alternative to traditional open or thoracoscopic approaches. Efficacy and safety of RAMIE and MIE in the surgical treatment for ESCC remains uncertain given the lack of high-level clinical evidence.

Methods: The RAMIE trial was designed as a prospective, multicenter, randomized, controlled clinical trial that compares the efficacy and safety of RAMIE and MIE in the treatment of resectable ESCC. From August 2017 to December 2019, eligible patients were randomly assigned to receive either RAMIE or MIE performed by experienced thoracic surgeons from 6 high-volume centers in China. Intent-to-treat analysis was performed.

Results: Significantly shorter operation time was taken in RAMIE (203.8 vs 244.9 min, P<0.001). Compared with MIE, RAMIE showed improved efficiency of thoracic lymph node dissection in patients who received neoadjuvant therapy (15 vs 12, P = 0.016), as well as higher achievement rate of lymph node dissection along the left recurrent laryngeal nerve (79.5% vs 67.6%, P = 0.001). No difference was found in blood loss, conversion rate, and R0 resection. The 90-day mortality was 0.6% in each group. Overall complications were similar in RAMIE (48.6%) compared with MIE (41.8%) (RR, 1.16; 95% CI, 0.92-1.46; P = 0.196). Besides, the rate of major complications (Clavien-Dindo classification ≥ III) was also comparable (12.2% vs 10.2%, P = 0.551). RAMIE showed similar incidences of pulmonary complications (13.8% vs 14.7%; P = 0.812), anastomotic leakage (12.2% vs 11.3%; P = 0.801), and vocal cord paralysis (32.6% vs 27.1%, P = 0.258) to MIE.

Conclusions: Early results demonstrate that both RAMIE and MIE are safe and feasible for the treatment of ESCC. RAMIE can achieve shorter operative duration and better lymph node dissection in patients who received neoadjuvant therapy. Long-term results are pending for further follow-up investigations.

Trial registration: ClinicalTrial.gov Identifier: NCT03094351.