Current status of lymph node dissection in gastric cancer.

Gastrectomy with lymph node (LN) dissection has been regarded as the standard surgery for gastric cancer (GC), however, the rational extent of lymphadenectomy remains controversial. Though gastrectomy with extended lymphadenectomy beyond D2 is classified as a non-standard gastrectomy, its clinical significance has been evaluated in many studies. Although hard evidence is lacking, D2 plus superior mesenteric vein (No. 14v) LN dissection is recommended when harbor metastasis to No. 6 nodes is suspected in the lower stomach, and dissection of splenic hilar (No. 10) LN can be performed for advanced GC invading the greater curvature of the upper stomach, and D2 plus posterior surface of the pancreatic head (No. 13) LN dissection may be an option in a potentially curative gastrectomy for cancer invading the duodenum. Prophylactic D2+ para-aortic nodal dissection (PAND) was not routinely recommended for advanced GC patients, but therapeutic D2 plus PAND may offer a chance of cure in selected patients, preoperative chemotherapy was considered as the standard treatment for GC with para-aortic node metastasis. There has been no consensus on the extent of lymphadenectomy for the adenocarcinoma of the esophagogastric junction (AEG) so far. The length of esophageal invasion can be used as a reference point for mediastinal LN metastases, and the distance from the esophagogastric junction to the distal end of the tumor is essential for determining the optimal extent of resection. The quality of lymphadenectomy may influence prognosis in GC patients. Both hospital volume and surgeon volume were important factors for the quality of radical gastrectomy. Centralization of GC surgery may be needed to improve prognosis.