VASH1 and neuroendocrine neoplasm: The aim of the study was the quantitative determination of the VASH-1 and VEGF-A concentrations in serum of patients with neuroendocrine tumors and to evaluate its association with the demographic data (age, gender), BMI, the location of the primary tumor, histological grade, and metastasis, as well as selected biochemical parameters (glucose, total cholesterol, triglycerides) and risk factor (smoking).