[Effect of microvessel injury on the frequency of tumor cells' lodging in them]

The action of local laser-induced microvascular injury on the frequency of tumour-cell lodgement and on the ability of these cells to migrate out of the microvessel lumen was studied. Intravital TV-microscope with a videotape recorder and an ultra-voilet laser was used. Ascites Saidel hepatoma cells were injected into the blood stream of rats. Lodgement of tumour cells in the mesenteric vessels was observed but rarely (11%). The lodged cells adhered to the microvascular wall and gradually migrated from the lumen. The injury of the wall with laser beam results in the formation of microthrombi and in increase in the frequency of lodgement of the tumour cells in these vessels: 82% against 11%, but migration of these cells decreased. The data obtained supported the significance of the microthrombus formation in the metastatic process. However, this role is not one-sided since on the background of increased frequency of adhesion of the tumour cells there was noted a decrease in their motility in the course of several hours after the lodgement in the microvessels.