Impact of the extent of recurrent laryngeal nerve lymphadenectomy on thoracic esophageal squamous cell carcinoma: a real-world multicentre study

OBJECTIVES: To determine the impact of recurrent laryngeal nerve (RLN) lymph node (LN) dissection on survival and postoperative complications in patients with oesophageal squamous cell carcinoma (ESCC). METHODS: Patients with cT1-4N0-3M0 thoracic ESCC who underwent oesophagectomy and two-field lymphadenectomy from three institutions were included. The entire cohort was divided into three groups that underwent the total two-field lymphadenectomy (T-2FL), standard two-field lymphadenectomy (S-2FL) or unilateral RLN-LN dissection plus S-2FL (U-2FL) based on the extent of RLN-LN dissection. Subgroup analyses were also performed and were stratified by treatment modality. RESULTS: Both the U-2FL and T-2FL groups had significantly superior outcomes compared with the S-2FL group (overall survival: U-2FL versus S-2FL: P = 0.002; T-2FL versus S-2FL: P < 0.001; recurrence-free survival: U-2FL versus S-2FL: P = 0.01; T-2FL versus S-2FL: P < 0.001). Moreover, no significant differences were observed between U-2FL and T-2FL regarding overall survival (P > 0.05) and recurrence-free survival (P > 0.05), irrespective of administration of neoadjuvant therapy plus oesophagectomy or upfront oesophagectomy. Additionally, the extent of RLN-LN dissection was not an independent predictor of stage migration (P = 0.14) but was for postoperative nodal upstaging (P = 0.02). Notably, S-2FL brought significantly lowered risk in postoperative complications, especially for RLN palsy, when compared with T-2FL (P = 0.002) but not U-2FL (P = 0.72). CONCLUSIONS: Adequacy of RLN-LN dissection is an important prognosticator for improved overall survival and recurrence-free survival in patients with thoracic ESCC. U-2FL may serve as an alternative to T-2FL in selected populations.