248. IMPACT OF INCREASING LYMPH NODE YIELD ON STAGING, MORBIDITY AND SURVIVAL AFTER ESOPHAGECTOMY FOR ESOPHAGEAL ADENOCARCINOMA

Abstract

Abstract Extended lymphadenectomy during esophagectomy for esophageal cancer may increase survival, but also increase morbidity. This study analyses changes in lymph node yield over time in a tertiary referral center, and investigates the influence of lymph node yield after transthoracic esophagectomy for esophageal adenocarcinoma on the number of positive lymph nodes, pathological N-stage, complications and survival. Consecutive patients undergoing transthoracic esophagectomy with gastric conduit reconstruction for esophageal adenocarcinoma between January 2010 and December 2020 were prospectively recorded (follow-up until January 2022). Lymph node yield was analyzed as continuous and dichotomous variable (≤30 vs. ≥31 nodes). The effect of lymph node yield on number of positive lymph nodes, complications, disease-free and overall survival was assessed in multivariable regression analyses. 585 patients were included. Median lymph node yield increased from 25 (IQR 20–34) in 2010 to 39 (IQR 32–50) in 2020. Higher lymph node yield was associated with more positive lymph nodes (≥31 vs. ≤30 IRR 1.39, 95%CI 1.11-1.75). In 258 (y)pN+ patients, the percentage of (y)pN3-stage increased with 14% between patients with ≤30 and ≥ 31 lymph nodes examined (p 0.014). Higher lymph node yield was not associated with more complications. Superior survival was seen in patients with ≥31 vs. ≤30 lymph nodes examined [DFS: HR 0.73, 95%CI 0.58-0.93, OS: HR 0.71, 95%CI 0.55-0.93)]. Lymph node yield increased significantly during the study period, as a result of several changes in the lymphadenectomy technique and separate submission of lymph node stations to pathology. A lymph node yield of ≥31 was associated with upstaging and superior survival after esophagectomy for esophageal adenocarcinoma, without increasing morbidity. Extended lymphadenectomy is therefore a valuable adjunct to multimodal treatment, and should be standard of care in esophageal cancer surgery, irrespective of choice of neoadjuvant therapy.