Survival Impact of Total Resected Lymph Nodes in Esophageal Cancer Patients With and Without Neoadjuvant Chemoradiation

BackgroundCurrent esophageal treatment guidelines suggest that, when more than 15 lymph nodes are detected, dissection should be done as the minimum requirement for staging in esophageal squamous cell carcinoma (ESCC) patients undergoing esophagectomy without induction chemoradiotherapy (CRT). However, for neoadjuvant CRT, there is limited information. We sought to clarify the role of lymphadenectomy in ESCC patients with and without neoadjuvant CRT.Patients and MethodsData on 3156 ESCC patients receiving esophagectomy with (group 1, n=1399) and without (group 2, n=1757) neoadjuvant CRT between 2008 and 2014 were collected from a national cancer registry in Taiwan. The impact of the resected lymph nodes on overall survival was assessed according to pathologic stages. A Cox regression model was used to identify prognostic factors for overall survival.ResultsFive-year overall survival rates were 35.6% for the entire group, 30.32% for group 1, and 39.55% for group 2 (p<0.0001 for group 1 vs group 2). The best cutoff value was 21 lymph nodes in both group 1 and group 2. In group 1, the independent prognostic factors included age54years, clinical N status, y-pathologic T, y-pathologic N, y-pathologic stage, grade, location, margin status, esophagectomy (thoracoscopic vs open), and number of total resected lymph nodes (21 vs>21). For group 2, the independent prognostic factors were gender, clinical stage, pathologic T, pathologic N, tumor length, grade, and margin status.ConclusionsExtent of lymphadenectomy was associated with survival in patients with neoadjuvant CRT followed by esophagectomy. The optimum lymphadenectomy should be modulated by pathologic stage.