OBJECTIVEWe analyzed the lymph node (MLNs) metastasis of thoracic esophageal squamous cell carcinoma (ESCC) to explore the patterns of lymphatic spread and the rational surgical procedure and extent of lymph node dissection for ESCC.

METHODSWe retrospectively evaluated 313 consecutive patients treated in our hospital between January 2010 and May 2014 who underwent minimally invasive esophagectomy (MIE) for ESCC. The information of lymph node status was obtained and the features of lymph node metastasis were analyzed.

RESULTSOf the 313 cases, 122 (39.0%) were found to have lymph node metastasis. In the 4461 dissected lymph nodes, metastasis was identified in 294 (6.6%) lymph nodes. The recurrent laryngeal nerve lymph nodes were the most frequent metastatic nodes with a metastasis rate of 25.2%, followed by the paracardiac and left gastric artery lymph nodes (18.2%). Chi-square test showed that the lymph node metastasis is associated with tumor invasion and tumor differentiation (P<0.001 for both). Metastases were more frequently found in the recurrent laryngeal nerve lymph nodes in patients with tumors in the upper third esophagus and with histologically poor differentiation (P<0.05 for both). The metastasis rate of para-cardiac and left gastric artery lymph nodes was associated with tumor in the lower third of esophagus, T stage and differentiation (all P<0.05). Logistic regression analysis showed that tumor differentiation and location are independent factors affecting the metastasis of recurrent laryngeal nerve lymph nodes (P<0.05 for all). T stage, tumor differentiation and location were independent factors associated with metastasis of para-cardiac and left gastric artery lymph nodes (P<0.05 for all).

CONCLUSIONS(1) Metastases of thoracic esophageal carcinoma are often found in the recurrent laryngeal nerve lymph nodes, para-cardiac and left gastric artery lymph nodes. (2) Extensive lymph node dissection should be performed for ESCC with poor differentiation and deep tumor invasion.