Characteristics and risk factors of lymph node metastases in esophageal carcinoma

Objective To investigate the status of lymph node metastases (LNM) of esophageal carcinoma and to identify the risk factors. Methods Clinical data of 308 patients who underwent esophagectomy with three-field lymphadenectomy during January 2006 and December 2010 were reviewed. Characteristics of LNM were studied. Results The average number of dissected lymph nodes was 35.6±14.5 in 308 patients. There were 197 patients (64％) had LNM. Logistic regression analysis showed that lymphatic vessel invasion(P=0.019) and deep tumor invasion(P＜0.001 ) were risk factors of LNM. The highest LNM site was paratracheal node (25.0％). The incidence of cervical LNM was 14.1％ in the middle thoracic carcinoma, higher than that of upper thoracic (7.3％) and lower thoracic (8.3％). Rate of LNM was lower in upper thoracic carcinomas than that in middle or lower ones (P=0.001). No significant difference of LNM was found among upper, middle and lower thoracic carcinoma for cervical or thoracic nodes. Lymphatic vessel invasion (P＜0.001)and metastases in paratracheal lymph nodes (P=0.014) were risk factors for cervical LNM. Conclusions LNM of esophageal carcinoma can be found in both directions vertically and skipped metastasis. Paratracheal lymph nodes involvement is an indicator for cervical lymphadenectomy in thoracic esophageal carcinoma. Key words: Esophageal neoplasms;  Lymph node metastases;  Paratracheal lymph nodes