Morphological study on permeability of pancreatic cancer microvessels

Abstract

Objective To explore the permeability of walls of pancreatic cancer microvessels for improving pancreatic cancer' s tumor-targeting drug therapy. Methods Ten moderately differentiated pan-creatic cancers from patients under pancreaticoduodenectomy in our hospital were divided into 4 groups, and center of tumors, margin of tumors, tumor adjacent tissues, and normal pancreatic tissues were exam-ined under a transmission electron microscope. Results Number of microvessels and transcellular holes in endothelial cells was significantly less in pancreatic cancers than in normal pancreases ( P < 0.05), as well as inter-endothehal gaps and transcellular holes of endothelial cells were not more broad in pancreatic cancers than in normal pancreases. Median of pore size of inter-endothelial gaps of endothehal cells of pan-creatic cancer microvessels was 12.8-13.2 nm,and 5-95 percentiles of those gaps were 0-24.4 nm. The widest segments of inter-endothelial gaps could reach 60.3-76.4 nm,when dilating. Pore size of transcellu-lar holes of endothelial cells of pancreatic cancer microvessels was about 40.0 nm. There were more torn opeuniugs of microvessel walls in tumor adjacent tissues, average size of which was about 516.3 urn. Con-clusion Pancreatic cancer has some heterogenicity of microvessels, including insufficient blood vessels and low permeability of the vessels. Key words: Pancreatic carcinoma; Mierovessel; Permeability; Vascular endothelial cell