Anatomical considerations of the infrapyloric artery and its associated lymph nodes during laparoscopic gastric cancer surgery

Background: Little is known about the vascular and lymphatic distribution of the pyloric antrum in the stomach. We focused on the infrapyloric region containing the infrapyloric artery (IPA) and lymph nodes. Methods: The anatomy of the IPA and its associated lymph nodes was clinically elucidated during 156 laparoscopic gastrectomies. Results: Most of the arteries originated from the anterior superior pancreatoduodenal artery (ASPDA, 64.2 %) or the root of the right gastroepiploic artery (RGEA, 23.1 %), but a small portion originated from the gastroduodenal artery (GDA, 12.7 %). The average lengths from the pyloric ring to the IPA proximal branch were 21.8 mm from the ASPDA, 20.6 mm from the RGEA and 9.0 mm from the GDA, a significantly shorter length than the other 2 variations. On average, 2.5 out of 10.0 nodes existed along the IPA. One patient, whose tumor was located close to the pylorus, had a metastatic node in this section. Conclusion: The IPA most commonly originates from the ASPDA and is associated with a certain number of lymph nodes. Vascular distribution from the IPA depends on the anatomic variation.