Vascular endothelial growth factor in prognosis of splenic malignant tumours in dogs

The aim of the study was to determine the levels of the vascular endothelial growth factor (VEGF) in the serum of dogs suffering from splenic malignant tumours, prior to splenectomy, as well as three and six months after the surgery. Tumours and blood samples were collected from 10 dogs of various breeds, aged between 7 and 13 years, and from 10 control animals. Tumour sections were fixed in 10% buffered formalin for 24 h. The type of tumour was determined according to the WHO classification. Blood samples were centrifuged and the obtained sera were subjected to immunoenzymatic assays to determine the VEGF levels. The median of VEGF levels in the serum of dogs suffering from splenic malignant tumours was 37.85 pg/mL (15.40-107.18 pg/mL). The highest values were observed in dogs with confirmed metastases (107.18 pg/mL and 65.43 pg/mL). The VEGF values in control group were between 0.1 pg/mL and 13.04 pg/mL. A comparative analysis of the VEGF levels against the animals' survival time indicated that VEGF overexpression may serve as a prognostic factor in cases of malignant tumours of the spleen.