A study of the lengthening and contractility of the surgical margins in digestive tract cancer

Background The lengthening and the contractility of the digestive tract were studied. Methods The stretched length of specimens was measured under pull weights of 500 g and 1000 g; the contracted length was measured in natural status and in 10% formalin fixation in vitro. The lengthening or contractility rate was calculated as the length difference divided by the natural length in vivo. Results The esophagus lengthened 16.5% at 500 g and 30.5% at 1,000 g, stomach 15% and 22.6%, small intestine 66.4% and 120%, large intestine 36% and 56%. In natural status in vitro, the esophagus contracted 44.5%, stomach 13.6%, small intestine 11.4%, and large intestine 15.6%; they continued to contract 12 to 24 hours after formalin fixation. Conclusions The lengthening and contractility of the digestive tract should be considered in evaluating the resection margin at surgery. The length of different conditions can be converted by the formula: Y = αX.