The Impact of Confluence Types of the Right Gastroepiploic Vein on No. 6 Lymphadenectomy During Laparoscopic Radical Gastrectomy

This study investigated anatomical variations in the confluence types of the right gastroepiploic vein (RGEV) to improve knowledge regarding no. 6 lymphadenectomy for laparoscopic gastrectomy.The RGEV drainage patterns of 144 patients who were diagnosed with gastric cancer and underwent laparoscopic distal gastrectomy at our department from July 2010 to June 2011 were prospectively collected and retrospectively analyzed, and we compared the impact of different drainage patterns on no. 6 lymphadenectomy.The RGEV confluence types were classified into 6 categories in this study. Types I, II, and III, which were observed in 53 (36.8%), 27 (18.8%), and 21 (14.6%) cases, respectively, were the most frequently found during gastrectomy. All 3 of these types included a gastropancreatic trunk and were defined as the gastropancreatic group (GP group). In addition, 15 cases (10.4%) were categorized as type IV, 19 (13.2%) were categorized as type V, and 9 (6.3%) were categorized as type VI. These 3 types, which could form a gastrocolic trunk, were defined as the gastrocolic group (GC group). No significant differences were found with respect to the clinicopathological characteristics, postoperative morbidity, perioperative mortality, and 3-year overall survival rates after surgery between the 2 groups (all P>0.05). However, the mean no. 6 lymph node (No. 6 LN) dissection time, the mean blood loss due to No. 6 LN dissection and the rate of infrapyloric vascular injury were significantly increased in the GC group compared with the GP group (all P<0.05).The RGEV exhibits 6 types of drainage patterns, and the division points of this vein during laparoscopic gastrectomy depend on the different drainage patterns. For types IV, V, and VI, the surgeon should carefully vascularize and divide the RGEV above its confluences during surgery.