Abstract：
BACKGROUND: Neoadjuvant chemoradiotherapy (nCRT) and surgery have been recommended as the standard treatments for locally advanced esophageal squamous cell carcinoma (ESCC). In addition, nodal metastases decreased in frequency and changed in distribution after neoadjuvant therapy. This study aimed to examine the optimal strategy for lymph node dissection (LND) in patients with ESCC who underwent nCRT.
METHODS: The hazard ratios (HRs) for overall survival (OS) and disease-free survival (DFS) were calculated using the Cox proportional hazard model. To determine the minimal number of LNDs (n-LNS) or least station of LNDs (e-LNS), the Chow test was used.
RESULTS: In total, 333 patients were included. The estimated cut-off values for e-LNS and n-LNS were 9 and 15, respectively. A higher number of e-LNS was significantly associated with improved OS (HR: 0.90; 95% CI 0.84-0.97, P = 0.0075) and DFS (HR: 0.012; 95% CI: 0.84-0.98, P = 0.0074). The e-LNS was a significant prognostic factor in multivariate analyses. The local recurrence rate of 23.1% in high e-LNS is much lower than the results of low e-LNS (13.3%). Comparable morbidity was found in both the e-LNS and n-LND subgroups.
CONCLUSIONS: This cohort study revealed an association between the extent of LND and overall survival, suggesting the therapeutic value of extended lymphadenectomy during esophagectomy. Therefore, more lymph node stations being sampled leads to higher survival rates among patients who receive nCRT, and standard lymphadenectomy of at least 9 stations is strongly recommended.
METHODS: The hazard ratios (HRs) for overall survival (OS) and disease-free survival (DFS) were calculated using the Cox proportional hazard model. To determine the minimal number of LNDs (n-LNS) or least station of LNDs (e-LNS), the Chow test was used.
RESULTS: In total, 333 patients were included. The estimated cut-off values for e-LNS and n-LNS were 9 and 15, respectively. A higher number of e-LNS was significantly associated with improved OS (HR: 0.90; 95% CI 0.84-0.97, P = 0.0075) and DFS (HR: 0.012; 95% CI: 0.84-0.98, P = 0.0074). The e-LNS was a significant prognostic factor in multivariate analyses. The local recurrence rate of 23.1% in high e-LNS is much lower than the results of low e-LNS (13.3%). Comparable morbidity was found in both the e-LNS and n-LND subgroups.
CONCLUSIONS: This cohort study revealed an association between the extent of LND and overall survival, suggesting the therapeutic value of extended lymphadenectomy during esophagectomy. Therefore, more lymph node stations being sampled leads to higher survival rates among patients who receive nCRT, and standard lymphadenectomy of at least 9 stations is strongly recommended.
摘要：
背景：新辅助放化疗（nCRT）和手术已被推荐为局部晚期食管鳞状细胞癌（ESCC）的标准治疗方法。此外,新辅助治疗后，淋巴结转移的频率降低，分布改变。本研究旨在研究接受nCRT的ESCC患者淋巴结清扫（LND）的最佳策略。
方法：使用Cox比例风险模型计算总生存期（OS）和无病生存期（DFS）的风险比（HR）。要确定LND的最小数量（n-LNS）或LND的最小站（e-LNS），使用了Chow测试。
结果：总计，包括333名患者。e-LNS和n-LNS的估计截止值分别为9和15。较高的e-LNS数量与改善的OS（HR：0.90;95％CI0.84-0.97，P=0.0075）和DFS（HR：0.012;95％CI：0.84-0.98，P=0.0074）显着相关。在多变量分析中，e-LNS是一个重要的预后因素。高e-LNS的局部复发率为23.1％，远低于低e-LNS的结果（13.3％）。在e-LNS和n-LND亚组中发现了相当的发病率。
结论：这项队列研究揭示了LND的程度和总生存期之间的关联，提示食管切除术中扩大淋巴结清扫术的治疗价值。因此,更多的淋巴结被采样导致谁接受nCRT患者的生存率更高，和标准的淋巴结清扫至少9站是强烈建议。
方法：使用Cox比例风险模型计算总生存期（OS）和无病生存期（DFS）的风险比（HR）。要确定LND的最小数量（n-LNS）或LND的最小站（e-LNS），使用了Chow测试。
结果：总计，包括333名患者。e-LNS和n-LNS的估计截止值分别为9和15。较高的e-LNS数量与改善的OS（HR：0.90;95％CI0.84-0.97，P=0.0075）和DFS（HR：0.012;95％CI：0.84-0.98，P=0.0074）显着相关。在多变量分析中，e-LNS是一个重要的预后因素。高e-LNS的局部复发率为23.1％，远低于低e-LNS的结果（13.3％）。在e-LNS和n-LND亚组中发现了相当的发病率。
结论：这项队列研究揭示了LND的程度和总生存期之间的关联，提示食管切除术中扩大淋巴结清扫术的治疗价值。因此,更多的淋巴结被采样导致谁接受nCRT患者的生存率更高，和标准的淋巴结清扫至少9站是强烈建议。
