Background: It is proposed by International Union Against Cancer (UICC) and American Joint Committee on Cancer (AJCC) that at least 6 lymph nodes (LN) should be removed during resection of esophageal cancer for an accurate N classification. However, large series evidence is needed. The aim of this study is to assess the impact of total number of removed LNs during esophagectomy on UICC-TNM staging and long-term survival.
Materials and methods: The clinicopathological data and follow-up results of 1098 patients with advanced esophageal carcinoma who underwent an esophagectomy were analyzed.
Results: The survival experience of group A (removed LNs <6) was worse than that of group B (removed LNs > or = 6). With the stratification analysis according to N and TNM stage, for patients with pN0 cancers, the survival in group A was worse than that in group B (P = .003), while in patients with 1 and > or = 2 positive LNs, the survival experience was similar (P = .919 and .182, respectively). A significant difference in survival in patients at stage IIa was observed between group A and group B (P = .005). However, the survival in patients at stage IIb and stage III was not different between the two groups (P = .302 and 0.108, respectively).
Conclusions: For advanced esophageal carcinoma, if the number of resected LNs per operation is less than 6, an occult positive regional LN might be missed, resulting in an inaccurate N classification. The minimum of 6 LNs removed for esophageal cancer recommended by UICC and AJCC is rational and should be complied with.