Is Routine Subcarinal Lymph Node Dissection Necessary in Superficial Esophageal Squamous Cell Carcinoma? A Propensity Score Matching Analysis

Background: The purpose of this study was to investigate the impact of subcarinal lymph node dissection on short-term and long-term outcomes after esophagectomy in patients with superficial esophageal squamous cell carcinoma (ESCC). Methods: From January 2010 to December 2015, 490 patients with pT1 ESCC were enrolled in the study. Patients in subcarinal dissection or non-dissection group were matched randomly in a 2:1 ratio, eventually, 255 patients were selected for further statistical analysis. Results: The metastasis rate of subcarinal lymph nodes in superficial ESCC was 1.24% and significantly lower than the other stations (7.14-9.96%). Compared with dissection group, non- dissection group had shorter operation time (193±35 vs. 204±39, P=0.016), less blood loss (157±48 vs. 178±29, P=0.011) as well as lower incidence of pulmonary complications (9.4 vs. 20%, P=0.032). At a median follow-up of 46 months, the recurrent rate in each group was similar (16.5 vs. 15.3%, P=0.809). Survival analysis revealed no overall survival (P=0.992) and disease-free survival (P=0.665) reductions in non-dissection group. In univariate and multivariate analyses, subcarinal lymph node dissection was not a predictive factor of overall and disease-free survival in superficial ESCC. Conclusion: Subcarinal lymph node dissection was not beneficial and could be omitted in superficial ESCC.