Mediastinal Lymphadenectomy Strategy for Siewert II Adenocarcinoma of the Esophagogastric Junction: A Retrospective Cohort Study

Background Siewert type II adenocarcinoma of the esophagogastric junction (AEG) exhibits complex bidirectional lymph node metastasis. This retrospective study investigated the recurrence and mortality risks associated with different ranges of mediastinal lymph node dissection. Methods We retrospectively analyzed 221 Siewert type II AEG patients who underwent radical surgery (McKeown or Left Thoracotomy (LT) approach) between June 2016 and October 2023. Patients were categorized based on lymphadenectomy extent: complete mediastinal and abdominal lymph node dissection (CMAD) group or middle/lower mediastinal and abdominal lymph node dissection (MLMAD) group. And those with CMAD at the same setting were matched in a 1:1 propensity score-matched (PSM) ratio to MLMAD patients. A prognosis analysis for CMAD and MLMAD patients by Kaplan–Meier curves was conducted. Cox regression analysis was performed to evaluate the risk factor of enrolled patients. Results CMAD significantly improved OS (HR = 0.37, 95%CI:0.23–0.60; P < 0.001) and DFS (HR = 0.36, 95%CI:0.22–0.58; P < 0.001) over MLMAD before PSM ; benefits persisted after PSM (OS HR = 0.44, P = 0.01; DFS HR = 0.44, P = 0.02). Upper mediastinal metastasis occurred in 4.3% of patients; The dissection of upper mediastinal stations (particularly 2R, 4R, and 8U) contributed to the observed survival benefit. Dissecting > 11 nodes correlated with improved survival. McKeown facilitated superior upper mediastinal and abdominal lymphadenectomy compared to LT (P < 0.001), without increasing complications or hospital stay. Conclusion Our findings suggest that a surgical strategy incorporating complete mediastinal and abdominal lymphadenectomy, when performed in selected patients at a high-volume center, is associated with superior survival outcomes compared to a more limited dissection.