[The effect of chemotherapy on endothelial function and microcirculation in patients with gastric cancer].

To evaluate and study the dynamics of endothelial dysfunction instrumental indicators, vascular wall stiffness and microcirculation state in patients with gastric cancer (adenocarcinoma) before and after chemotherapy; compare it with the results obtained from healthy volunteers and patients with cardio-vascular diseases. The study included 65 people: 25 healthy volunteers, 15 patients with known cardio-vascular diseases (CVD) and 25 patients with histologically confirmed gastric cancer (adenocarcinoma) stage 2-4 who underwent surgical treatment followed by chemotherapy according to the FOLFOX, XELOX, and XP regimes. For non-invasive assessment of the vascular wall's state of large vessels and microcirculation, all patients in the main group underwent computer nailfold capillaroscopy and finger photoplethysmography before chemotherapy and within a month after the completion of the last course. For healthy volunteers and patients with CVD, the above studies were performed once during the examination. The data obtained indicate a significant increase in the reflection index of small muscle arteries (RI) and the stiffness index of large conducting arteries (aSI) during chemotherapy. In cancer patients, even before the treatment, endothelial dysfunction was detected, which significantly worsened after treatment (occlusion index (IO) before and after chemotherapy 1.7 (1.38; 1.9) vs. 1.3 (1.2; 1.5), p<0.0002, respectively). Significant differences in the compared indices in cancer patients and CVD group were revealed only after chemotherapy. Significant structural and functional disorders of capillaries were noted in the studied groups, which also worsened during chemotherapy in the main group (density of the capillary network at rest 43.23cap/mm2 vs. 42.19cap/mm2, p <0.01, respectively; density of the capillary network after the reactive hyperemia test 46.77cap/mm2 vs. 44.11cap/mm2, p<0,02, respectively). In this study, for the first time, the dynamics of endothelial dysfunction indicators, vascular wall stiffness and microcirculation state in patients with gastric cancer were studied, and a reliable increasing of these changes was proved during chemotherapy. The results indicate the need for a further search for accurate and effective methods of identifying early signs of close and distant vasculotoxicity, the development of individual prevention programs in order to significantly reduce the risk of cardiovascular events during and after chemotherapy.