649. MODIFIED EN BLOC ESOPHAGECTOMY WITH TOTAL LYMPHADENECTOMY IN PATIENTS WITH RESIDUAL TUMOR AFTER NEOADJUVANT CHEMORADIOTHERAPY FOR ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Abstract

Abstract The optimal type of esophagectomy and extent of mediastinal lymphadenectomy for patients who had received neoadjuvant chemoradiotherapy for esophageal squamous cell carcinoma (ESCC) remain debatable. We hypothesized that a more radical resection could be associated with better survival without adding morbidity. Data of patients who received trimodal treatments (neoadjuvant chemoradiotherapy followed by surgery) for ESCC between 2016 and 2021 in a single center were analyzed. Modified en bloc esophagectomy (mEBE) is defined as removal of the esophagus tube en bloc with adjoining locoregional soft tissue and lymph nodes, using the concept of mesoesophagus. Total lymphadenectomy includes dissection of lymph nodes around bilateral recurrent laryngeal nerves. Outcomes after mEBE with total lymphadenectomy were compared to those after conventional esophagectomy (CE). A total of 154 patients, including 42 and 112 receiving mEBE and CE, respectively, were included. Compared to CE, the mEBE was associated with a longer operative time (560 vs. 540 min, p<0.001) and higher total resected lymph node (19 vs. 17, p=0.001); whereas the complication rates and length of stay were similar between two groups. There was no overall survival (OS) difference between mEBE and CE groups in patients with ypT0N0 stage. However, in patients with residual tumors (non-ypT0N0), the 3-year OS rates were 58.5% and 40.8% in mEBE and CE groups, respectively (p=0.010). In patients with ESCC, mEBE with total lymphadenectomy after neoadjuvant chemoradiotherapy is safe without adding perioperative morbidity. Moreover, it is associated with better OS compared to CE, especially in patients who have residual tumor after neoadjuvant treatments.