Radical Lymph Node Dissection in Primary Esophagectomy for Esophageal Squamous Cell Carcinoma

Background. Subtotal esophagectomy with radical lymph node dissection (RLND) remains an effective therapeutic strategy for localized esophageal squamous cell carcinoma (ESCC). However, controversy exists regarding the extent to which RLND should be performed. We reappraised the prognostic impact and accurate nodal staging of RLND in ESCC. Methods. The data from 101 ESCC patients (mean age, 57.5 years; 93 men) who underwent primary subtotal esophagectomy were retrospectively collected. Candidate variables, including the number of total dissected lymph nodes (TDLN [subgrouped into TDLN less than 13, TDLN 13 to 40, and TDLN more than 40]), were evaluated to determine their prognostic impacts and hazard ratio (HR). Results. Fewer TDLN (p < 0.001; HR 9.011, 2.449, and 1.000 for TDLN less than 13, TDLN 13 to 40, and TDLN more than 40, respectively), tumor length exceeding 3.5 cm (p < 0.001; HR 3.321), resection margin invasion (p < 0.001; HR 14.493), and positive nodal status (p = 0.002; HR 2.730) were independent predictors of a poor prognosis. Considering the 54 node-negative patients, more TDLN correlated with improved survival (p = 0.001). Risk analysis demonstrated that one fewer TDLN could contribute to an increased HR of 1.047 (p = 0.014). However, RLND involving more TDLN appeared to lose the prognostic impact for the 47 node-positive patients (p = 0.072). Furthermore, the number of positive dissected lymph nodes remained at approximately 4 if the number of TDLN exceeded 20. Conclusions. For N-negative or N-positive ESCC patients undergoing primary surgical resection, the number of TDLN influenced their prognosis or nodal staging accuracy, respectively. At least 20 TDLN were necessary for N-positive patients. (C) 2015 by The Society of Thoracic Surgeons