Vasculotoxicity of Chemotherapy: Assessment.f Endothelial Dysfunction Biomarkers' Levels in Gastric Cancer Patients

Aim To evaluate dynamics of biomarkers for endothelial dysfunction (ED), including endothelin-1 (ET-1) and von Willebrand factor (VWF) in patients with stomach cancer (adenocarcinoma) before and after polychemotherapy (PCT); to compare these results with respective values in healthy volunteers and patients with cardiovascular diseases (CVD); to study correlations of the ED biomarkers with indexes of instrumental evaluation of endothelial dysfunction.Material and methods The study included 75 participants, including 25 healthy volunteers (control group), 25 patients with documented CVDs (arterial hypertension + ischemic heart disease), and 25 patients of the main group with histologically documented stage II-IV stomach cancer (adenocarcinoma) who received different courses of PCT with platinum-based agents (oxaliplatin, cisplatin) and fluoropyrimidines (5 fluorouracil, capecitabin). Laboratory measurement of ED biomarkers, computerized nailfold video capillaroscopy (CNVC), and finger laser photoplethysmography (PPG) (methods for noninvasive evaluation of vascular wall and ED), electrocardiography, 24-h ECG Holter monitoring, and echocardiography (EchoCG) were performed for all patients of the main group prior to PCT and within one months after the last course completion. This evaluation was performed once for healthy volunteers and patients of the CVD group upon inclusion into the study.Results In the main group, ET-1 levels were non-significantly lower than normal and did not change during the courses of antitumor treatment (0.95 [0.6; 1.4] and 0.94 [0.7; 1.4] pg /ml (р<0.9) before and after PCT, respectively). Statistically significant differences were found between the control group and oncological patients after the treatment (р<0.04). Levels of VWF remained within the normal range in all examined participants and did not significantly differ between study groups, including oncological patients before and after the specific treatment (р>0.05 for all comparisons). The correlation analysis detected significant correlations of ET-1 levels with functional disorders of microcirculation, ET-1 with the occlusion index (rs=0.56; p=0.005), ЕТ-1 with percentage of capillary restoration (PCR, rs= -0.72; p=0.018) and with the incidence rate of supraventricular extrasystole (rs=0.48; p=0.032).Conclusion The dynamics of ED biomarkers was studied for the first time in patients with stomach cancer receiving a specific antitumor therapy. Although no significant changes in ЕТ-1 and VWF were observed during the PCT (probably due to exhaustion of the endothelial system and a small patient sample), these indexes can be considered as early vasculotoxicity markers due to the presence of significant correlations with indexes of impaired endothelial function according to the results of instrumental evaluation.