Аннотация:The paper demonstrates the results of a study of experimental SN-12C xenograft vascular network formation using optoacoustic microscopy. A sevenfold increase in vascularity during tumor growth from days 7 to 121 was shown. The possibility of monitoring the development of individual vessels inside the tumor node has been demonstrated. The data obtained are important for understanding the mechanisms of development of the tumor vascular system and may be useful in testing antiangiogenic therapeutic agents.