Impact of intraoperative recurrent laryngeal nerve monitoring on minimally invasive esophagectomy outcomes for esophageal cancer: a meta-analysis of case-control studies

Esophagectomy and lymphadenectomy for esophageal cancer carry an inherent risk of recurrent laryngeal nerve (RLN) injury. Intraoperative nerve monitoring (IONM) may help prevent RLN damage, though evidence on its effectiveness is still limited. This systematic review and meta-analysis (SRMA) evaluate the feasibility and efficacy of IONM during minimally invasive esophagectomy (MIE) for esophageal cancer. This SRMA followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines, with a registered protocol on PROSPERO (CRD42022367916). Two independent authors conducted a comprehensive literature search across multiple databases, screening studies on MIE for esophageal cancer using IONM. Case-control studies were included, focusing on the RLN palsy (RLNP) rate as the primary outcome. A total of 11 studies involving 1907 patients (IONM group: 752 patients; non-IONM group: 1155 patients) were included in the SRMA. IONM significantly reduced the incidence of RLNP (OR = 0.47, P < 0.001). Length of hospital stay (LOHS) and lower respiratory tract infection (LRTI) rates were significantly reduced with IONM use. No significant differences were observed in anastomotic leak, chylothorax, total number of lymph nodes dissected, operation time, aspiration rates, or intraoperative blood loss. The pooled sensitivity and specificity of IONM for detecting RLN injury were 83.3% and 81%, respectively. IONM during MIE significantly reduces the incidence of RLNP, postoperative LRTI, and shortens the LOHS, without adding operative risks. Further research is needed to evaluate its long-term survival benefits and cost-effectiveness.