Prognostic impact of lymph node harvest for patients with node-negative esophageal squamous cell carcinoma: a large-scale multicenter study

Qi-Xin Shang; Yu-Shang Yang; Li-Yan Xu; Hong Yang; Yin Li; Yi Li; Zhi-Yong Wu; Jian-Hua Fu; Xiao-Dong Yao; Xiu-E Xu; Jian-Yi Wu; Long-Qi Chen

doi:10.21037/jgo-20-371

Prognostic impact of lymph node harvest for patients with node-negative esophageal squamous cell carcinoma: a large-scale multicenter study

J Gastrointest Oncol. 2021 Oct;12(5):1951-1962. doi: 10.21037/jgo-20-371.

Authors

Qi-Xin Shang¹, Yu-Shang Yang¹, Li-Yan Xu², Hong Yang³, Yin Li⁴, Yi Li⁴, Zhi-Yong Wu², Jian-Hua Fu³, Xiao-Dong Yao², Xiu-E Xu², Jian-Yi Wu², Long-Qi Chen¹

Affiliations

¹ Department of Thoracic Surgery, West China Hospital of Sichuan University, Chengdu, China.
² Department of Oncology Surgery, Shantou Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
³ Department of Thoracic Oncology, Sun Yat-sen University Cancer Center, Guangzhou, China.
⁴ Department of Thoracic Surgery, Cancer Hospital Chinese Academy of Medical Sciences, Beijing, China.

Abstract

Background: We examined the association between the number of resected lymph nodes and survival to determine the optimal lymphadenectomy for thoracic esophageal squamous cell carcinoma (ESCC) patients with negative lymph node.

Methods: We included 1,836 patients from Chinese three high-volumed hospitals with corresponding clinicopathological characters such as gender, age, tumor location, tumor grade and TNM stage of patients. The median follow-up of included patients was 45.7 months (range, 1.03-117.3 months). X-Tile plot was used to identify the lowest number of lymphadenectomy. The multivariate model's construction was in use of parameters with clinical significance for survival and a nomogram based on clinical variable with P<0.05 in Cox regression analysis. Both two models were validated using a cohort extracted from the Surveillance, Epidemiology, and End Results (SEER) 18 registries database between 1975 and 2016 (n=951).

Results: More lymphadenectomy numbers were significantly associated with better survival in patients both in training cohort [hazard ratio (HR) =0.980; 95% confidence interval (CI): 0.971-0.988; P<0.001] and validation cohort (HR =0.980; 95% CI: 0.968-0.991; P=0.001). Cut-off point analysis determined the lowest number of 9 for thoracic ESCC patients in N0 stage through training cohort (C-index: 0.623; sensitivity: 80.7%; 1 - specificity: 72.5%) when compared with 10 in validation cohort (C-index: 0.643; sensitivity: 78.2%; 1 - specificity: 63.0%). The cut-off points of 9 were examined in training cohort and validated in the divided cohort from validation cohort (all P<0.05). Meanwhile, nomograms for both cohorts were constructed and the calibration curves for both cohorts agreed well with the actual observations in terms of predicting 3- and 5-year survival, respectively.

Conclusions: Larger number for lymphadenectomy was associated with better survival in thoracic ESCC patients in N0 stage. Nine was what we got as the lowest number for lymphadenectomy in pN0 ESCC patients through this study, and our result should be confirmed further.

Keywords: Esophageal squamous cell carcinoma (ESCC); node-negative patients; optimal lymphadenectomy number; prognosis.