[Analysis of lymph node metastasis in the thoracic esophageal squamous cell carcinoma]

To assess the metastatic frequency in different groups of lymph nodes and its influencing factors of the thoracic esophageal squamous cell carcinoma (ESCC) in order to determine the extent of lymphadenectomy during esophagectomy.

The clinical data of 730 patients with ESCC who underwent esophagectomy and lymphadenectomy were analyzed retrospectively.

Of 730 patients, 166 had metastasis to the para-esophageal lymph nodes (22.7%), 90 to the left gastric artery lymph nodes (12.3%), 67 to the lymph nodes around gastric cardia, and 15 to the subcrinal lymph nodes (2.1%). Univariate analysis showed that metastasis to the subcrinal lymph node was positively correlated with the length and differentiation of tumor (P < 0.05), but it was not correlated with any the above parameters when analyzed by multivariate analysis. The metastasis to the para-esophageal lymph node was positively correlated with the length, invasion depth and differentiation of tumor by univariate and multivariate analysis (P < 0.05). The metastasis to the lymph nodes around gastric cardia and metastasis to left gastric artery lymph nodes were positively correlated with the position and invasion depth of tumor by univariate and multivariate analysis (P < 0.05).

Lymph nodes of the para-esophagus, gastric cardia and left gastric artery usually have high frequency to harber mestastasis, therefore, it was suggested that the lymph nodes in these groups should be dissected during esophagectormy with two-field lymphadenectomy for thoracic esophageal squamous cell carcinoma. Whereas for those patients with the lesion < 3 cm in length or with tumor invasion confined within the esophageal wall or with a lesion located at the upper or lower third of the thoracic esophagus, the subcrinal lymph nodes may not be necessarily dissected.