The prevalence of lymph node metastasis for pathological T1 esophageal cancer: a retrospective study of 143 cases

To evaluate the prevalence, pattern and risk factors of lymph node metastasis (LNM) for pathological T1 (pT1) esophageal cancer (EC).

The clinical data of 143 cases of pT1 patients who underwent esophagectomy and lymph node dissection during January 2011 and July 2016 were reviewed, including 120 male patients and 23 female patients with a median age of 60 years. The pattern of LNM was analyzed and the risk factors related to LNM were assessed by logistic regression analysis. The nomogram model was used to estimate the individual risk of lymph node metastasis.

Of 143 patients with T1 tumors, 25 patients had LNM, and the LNM rate was 17.5%. The LNM rate was 8.0% for T1a tumors, and 22.5% for T1b tumors. The logistic regression analysis showed that the depth of tumor infiltration (P < 0.05), tumor size (P < 0.01), tumor location (P < 0.05), and tumor differentiation (P < 0.01) were independent risk factors related to LNM for T1 EC. These four parameters allowed the compilation of a nomogram to estimate the individual risk of LNM. Tumor differentiation (P < 0.05) was an independent risk factor related to LNM for T1a tumors, and tumor size (P < 0.05) and tumor location (P < 0.05) were independent risk factors related to LNM for T1b tumors. Of 25 patients with LNM, one patient had cervical LNM, 15 patients with thoracic LNM, and 17 patients with abdominal LNM. The relatively highest LNM sites were laryngeal recurrent nerve (n = 8), the left gastric artery (n = 8), right and left cardiac (n = 6) and thoracic paraesophageal (n = 5).

T1 EC has a relatively high LNM rate, and the depth of tumor infiltration, tumor size, tumor location and tumor differentiation are correlated with LNM. The LNM risk and extent must be considered comprehensively in decision-making of a better surgical treatment and lymph node dissection strategy.