Benefit of mediastinal and para-aortic lymph-node dissection for advanced gastric cancer with esophageal invasion

BACKGROUND AND OBJECTIVES: Lymph-node dissection in gastric cancers with esophageal invasion (AGCE) is of current interest. This study examined the significance of inferior mediastinal lymph-node (IM) and para-aortic lymph-node (PA) dissection for this type of cancer. METHOD: Two hundred and seventy cases of AGCE were clinicopathologically reviewed. An index of estimated benefit from lymph-node dissection (IEBLD) was calculated from the frequency of lymph node metastasis in IM and PA, and from 5-year survival rates for metastatic cases. RESULTS: Among the cases of AGCE, IM and PA metastasis rates were 18.1% and 22.2%, respectively. The IEBLD for IM and PA was similar to that for dissection of the second-tier lymph nodes around the celiac axis. The IM metastasis rate was 0.0% for esophageal invasion of 0-9 mm, 2.2% for 10-19 mm, 17.8% for 20-29 mm, and 21.7% for 30-39 mm of esophageal invasion. CONCLUSION: AGCE is associated with a high rate of PA metastasis, and with a high rate of IM metastasis when esophageal invasion exceeds 2 cm. Since dissection of IM and PA achieved the same benefit as dissection of second-tier lymph nodes, we recommend thorough dissection of these lymph nodes.