[Microvascular changes in the pyloric ring and duodenal invasion in carcinoma of the gastric antrum].

In this study, vascular perfusion of surgically removed specimen was carried out in 45 middle or late staged gastric antrum carcinomas and 5 gastric ulcers to observe the morphology of the microvasculature at the juncture of the stomach and the duodenum. It was found that: 1) The microvasculature on both side of the pylorus and the duodenum communicated through small arteriole and the morphology of the microvasculature varied with tumor-infiltrated depth. 2) The duodenum was found to be invaded by the tumor in only 2 cases in which the tumor was within 1.5 cm from the pyloric ring. 3) The mechanism by which the tumor invaded the duodenum was most likely resulted from direct extension through the interstitium when the microvasculature, the physiological and anatomical intact of the pyloric ring were destroyed by the tumor. 4) Based on the aforementioned observations, the authors propose that in gastric antrum carcinoma, the safe resection length of the duodenum is less than 3 cm when the tumor is 1.5 cm away from the pyloric ring, otherwise, more than 3 cm of the duodenum should be removed.