To investigate the value of routine subcarinal lymph node dissection in radical resection of esophageal cancer.

The clinical data of patients undergoing radical resection of esophageal cancer in Affiliated Hospital of North Sichuan Medical College between March 2013 and March 2016 were retrospectively analyzed. Patients were divided into dissection group (with subcarinal lymph node dissection, n=294) and non-dissection group (without subcarinal lymph node dissection, n=308). The basic characteristics were compared between two groups. The influencing factors of subcarinal lymph node metastasis were explored by Logistic regression analysis, and the perioperative parameters were compared between two groups.

A total of 602 patients were included, with an average of 11.75 dissected lymph nodes in each patient. There were 202 cases of lymph node metastasis, which accounted for 33.6%. The mean number of dissected lymph nodes in each patient in dissection group was 2.87, and there were 20 patients (6.8%) with lymph node metastasis in dissection group. Univariate analysis indicated that the rates of subcarinal lymph node metastasis in patients staged Tis/T1, T2, T3 and T4 were 0, 1.4%, 10.2% and 13.6%, respectively (χ²=16.407, P<0.01), the rates of subcarinal lymph node metastasis in those staged N0, N1, N2 and N3 were 0, 12.9%, 20.5% and 60.0%, respectively (χ²=46.099, P< 0.01), the rates of subcarinal lymph node metastasis in those with different length of esophageal cancers (≤3.0 cm, 3.1 to 5.0 cm, >5.0 cm) were 2.0%, 7.5% and 13.3%, respectively (χ²=8.253, P<0.05), and the rate of subcarinal lymph node metastasis was not significantly related to age, gender, tumor location, surgical path, tumor differentiation and number of dissected lymph nodes (P>0.05). Multivariate analysis indicated that T staging and infiltration depth of esophageal cancer were related to subcarinal lymph node metastasis (P<0.05). The incidence of pulmonary and thoracic cavity complications and operation time in dissection group were higher and longer than those in non-dissection group (P<0.05).

Tumor infiltration depth and N staging are related to subcarinal lymph node metastasis of esophageal cancer. Subcarinal lymph nodes may be dissected routinely in esophageal cancer patients with esophageal fiber membrane infiltration, however, it may also increase the incidence of complications and operation time.