A comparison of two methods of lymph node dissection along the left recurrent laryngeal nerve in McKeown minimally invasive esophagectomy

Background: Lymph nodes dissection in esophagectomy is an essential procedure for radical resection, which can not only provide more accurate staging but may also improve survival, while it is technically challenging and may lead to recurrent laryngeal nerve (RLN) paralysis. Numerous efforts have been directed to achieve the dissection of more LNs around the RLN and to lower the incidence of RLN palsy, including Bascule method and modified Bascule method. On this basis, we modified and applied a novel method which involves the en bloc dissection of lymph nodes dissection along the left RLN in McKeown minimally invasive esophagectomy (MIE). Methods: A total of 244 consecutive cases of lymphadenectomy along the left RLN during McKeown MIE at our institution between January 2018 and August 2021 were retrospectively analyzed. The cases were divided into two groups based on the methods of lymphadenectomy along the left RLN: 77 cases received the conventional method (CM group) and 167 cases received the novel method (NM group). The surgical outcomes, especially the impact of surgical proficiency on the outcomes of lymphadenectomy along the left RLN, were assessed and compared between the two groups. Results: Demographic data of the two cohorts were similar. The number of harvested lymph nodes (LNs) (total/abdomen/left RLN) in the NM group was markedly higher than that in the CM group (32 vs. 27, P=0.006; 11 vs. 9, P=0.038; 3 vs. 2, P=0.044). However, the number of harvested LNs from the chest or right RLN was not significantly different in the two groups. The hoarseness rate was 1.8% in the NM group, which was slightly but not notably lower than that of the CM group (1.8% vs. 2.6%, P=0.681). The incidence of LN metastasis along the left RLN was 13.9%, 15.6%, and 13.2% in the whole cohort, CM group, and NM group, respectively. Conclusions: Our novel method not only increased the number of LN dissections along left RLN but also slightly reduced the incidence of hoarseness. Therefore, this novel method of lymphadenectomy along the left RLN during McKeown MIE is safe and reliable.