70 IMPACT OF LYMPH NODE YIELD ON SURVIVAL IN PATIENTS UNDERGOING NEOADJUVANT CHEMORADIOTHERAPY FOLLOWED BY SURGERY FOR LOCALLY ADVANCED ESOPHAGEAL CANCER. (17th September 2021) - Guo, Xufeng
Abstract: : A survival benefit of neoadjuvant chemoradiotherapy (nCRT) added to surgery has been demonstrated and therefore is regarded as standard of care for patients with locally advanced esophageal cancer in many countries. It remains unclear whether it is necessary to perform extended lymphadenectomy for patients with esophageal squamous cell carcinoma (ESCC) after nCRT. This study aimed to evaluate the impact of lymph node yield (LNY) on survival in ESCC patients undergoing nCRT plus esophagectomy. Methods: Patients receiving R0 resection for locally advanced ESCC were included from the prospective randomized NEOCRTEC5010 trial [surgery (S) alone vs nCRT plus S]. With Cox proportional hazard regression models, the association between survival and LNY as a categorical variable (<20 vs ≥20 nodes) was analyzed in the nCRT group as well as the pCR subgroup. Results: Compared with the S group, the nCRT group achieved a better 5-year OS (65.9% vs 55.8%; P = 0.010). Less LNY [20 (IQR 15–27) vs 26 (IQR 19–35); P < 0.001] and positive nodes [0 (IQR 0–1) vs 1 (IQR 0–2.5); P < 0.001] were harvested in nCRT group compared to S group. The number of LNY was significantly associated with OS [HR, 0.363; 95% CI, 0.208–0.635; P < 0.001] and DFS (HR, 0.423; 95% CI, 0.249–0.719; P = 0.001) for patients in nCRT group. Furthermore, an increased LNY was not associated with worse postoperative complications. Conclusion: The benefit of a higher lymph node yield on overall and disease-free survival is identified for the patients with ESCC who received nCRT followed by esophagectomy. Therefore, an extended lymphadenectomy should be the standard of care after nCRT.