Prognostic significance of preoperative lymph node assessment for patients with stage pN0 esophageal squamous cell carcinoma after esophagectomy.

Abstract

Accurate preoperative lymph node (LN) staging is important for surgical treatments of esophageal squamous cell carcinoma (ESCC). The aim of the study was to investigate the role of preoperative lymph nodes assessment by computed tomography (CT) scans in prognostic estimates and lymph nodes dissection strategy. A total of 233 stage pN0 ESCC patients who underwent radical esophagectomy from 2009 to 2016 were included, with the last follow-up time in 2018. Survival analysis was conducted to assess the relationship between preoperative clinical LN metastasis and the prognosis of patients with pN0 ESCC. Ninety-nine patients were classified as clinical positive LN metastasis by CT scans, but were confirmed as stage N0 by postoperative pathological examination, and survival analysis suggested that these patients had relatively poorer prognosis (P=0.027). Cox regression analysis indicated that the clinical LN metastasis on CT scans was an independent negative prognostic factor for patients with pN0 ESCC (P=0.031). The number of LNs dissected affected the prognosis of pN0 patients. Patients with positive LN metastasis on CT would have better prognosis when the number of dissected LNs was equal to or more than 15 LNs (P=0.036). Especially for patients with higher T stage, they were would obtain prognostic benefit with at least 17 LNs dissected (P=0.037). On the other hand, for those with negative LN metastasis on CT, at least 12 LNs dissected indicated better prognosis (P=0.019). Preoperative LN assessment for ESCC patients is critically important, the optimal LN dissection number should refer to the preoperative CT performance.