During intra-arterial perfusion therapy of oral squamous cell carcinomas with bleomycin, circumscribed necrotic areas in the perfused region are observed in a few cases. These are usually located in the acral regions. As the cause, a lesion of the blood vessels with formation of microthrombosis could be demonstrated. Electron-microscopic observations of the blood vessels in five bleomycin-perfused tumor areas demonstrated lesions of the endothelium characterized by swelling of the cells, formation of intracytoplasmatic vacuoles and villous projections into the lumen of the vessel. In arterioles, separation of the endothelium from the underlying tissue, swollen smooth muscle cells and destruction of elastic lamellae were found. These were the pacemakers for the formation of thrombosis. A negative influence of the vascular lesions on the cytostatic effect on the tumor is likely. Vascular lesions also constitute one of the initial factors for the development of the bleomycin-induced lung lesion (bleomycin lung).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.