Priority of lymph node dissection for advanced esophagogastric junction adenocarcinoma with the tumor center located below the esophagogastric junction

To clarify the priority of lymph node dissection (LND) in advanced Siewert type II and III AEG, in which the center of the tumor is located below the esophagogastric junction (EGJ). Data in 395 patients with advanced Siewert type II or III AEG was analyzed retrospectively. The index of estimated benefit from LND (IEBLD) was used to evaluate the efficacy of LND for each nodal station. The mean number of dissected LNs did not differ significantly between patients with type II and III AEG, nor did the mean number of retrieved LNs at each station significantly differ between the 2 groups. According to the IEBLD, the dissection of parahiatal LNs (No.19 and 20) and LNs along the distal portion of the stomach (No.5, 6, and 12a) seemed unlikely to be beneficial, whereas the dissection of Nos.1–3, 7, 9 and 11p yielded high therapeutic benefit (IEBLD>3.0) in both groups. The IEBLDs of No.4d, 8a, and 10 were much higher in type III than in type II AEG cases. No.10 LND may improve survival for type III AEG cases (IEBLD = 2.9), especially for subgroups with primary tumors invading the serosa layer, undifferentiated cancers, macroscopic type 3–4 tumors and tumors ≥50 mm in size (all IEBLDs > 4.0). For advanced AEG located below the EGJ, the dissection of paracardial LNs, lesser curvature LNs, and LNs around the celiac axis would promote higher survival benefits regardless of the Siewert subtype. Patients with type III AEG, especially those with serosa-invasive tumors, undifferentiated tumors, macroscopic type 3–4 tumors and tumors ≥50 mm in size may obtain relatively higher survival benefits from No. 10 lymphadenectomy.