Relationship between parameters of tumor neoangiogenesis and lymphogenous metastasis in patients with rectal cancer

Angiogenesis (neoangiogenesis) characterized by the formation of new blood vessels from pre-existing vessels is the main condition for the intensive growth of the primary tumor. This process is characterized by a sequence of events beginning with vasodilation, separation of pericytes from the vascular wall with subsequent proliferation of endotheliocytes and formation of vascular glomeruli surrounded by stromal cells. Evaluation of the density of microvessels, as well as «vascular kidneys» (clusters of endotheliocytes) is the most widely used method for quantifying intracellular angiogenesis. The purpose of the study was to analyze the expression characteristics of markers of neoangiogenesis (CD34 and VEGFR) in tumor tissue and to evaluate their relationship with the parameters of lymphogenous metastasis in colorectal cancer. Material and methods. Surgical specimens from 130 patients with ypT1-4N0-2M0 stage of rectal cancer, who were treated at the Thoracic and Abdominal Department of Tomsk Cancer Research Institute, were analyzed. The standard techniques for histological and immunohistochemical examinations were used. Diagnose was made according to WHO classification (2010). The study included only cases with rectal adenocarcinoma. Results. When studying the density of microvessels and «vascular budding» in a tumor tissue using an antibody to CD34, it turned out that the density of microvessels in the submucosal layer of the rectum was higher in cases with the presence of lymphogenous metastases than in cases without lymphogenous metastasis. The microvessel density determined by the antibody to VEGFR in the mucosa, submucosal and muscle layers, as well as in the serosa of the rectum did not differ between groups with the presence or absence of lymphogenous metastases. The density of «vascular kidneys» in all layers of the rectum wall was not associated with lymphogenous metastasis. Conclusion. The study showed that the expression of molecular-biological markers of neoangiogenesis in tumor tissue of patients with rectal adenocarcinoma was associated with the parameters of lymphogenous metastasis