Vascular Endothelial Growth Factor (VEGF) as a biomarker for Cancer Associated Thrombosis: a meta-analysis

Cancer-associated thrombosis affects between 1 and 20% of all patients diagnosed with cancer and is associated with significant morbidity and poorer prognosis. VEGF is a potent angiogenic factor, produced by tumour cells, and released by platelets and is essential for tumour growth and progression as well as the promotion of thrombosis. Therefore, the potential of VEGF to be used as a biomarker to predict cancer-associated thrombosis requires further investigation. PubMed and OVID databases were systematically searched up to July 2023, and inclusion and exclusion criteria applied. Seven papers (1528 participants) were identified and included in the meta-analysis, three of which (922 participants) measured VEGF before a thrombotic event, and the remaining four (606 participants) which measured VEGF at the time of the thrombosis. Our results showed that although plasma and serum VEGF levels tended to be higher in those who subsequently developed thrombosis than those who did not (mean difference 70.2 pg/mL for serum, and 11.44 pg/mL for plasma VEGF, 95% CI -2.39 – 25.73, p= 0.10), this was not found to be statistically significant. However, analysis of VEGF following blood sampling at the time of thrombosis, showed a stronger statistically significant association between increased VEGF levels and presence of thrombosis (mean difference 117.02 pg/mL for serum, and 116.6 pg/mL for plasma VEGF, 95% CI 55.42 - 190.82, p = 0.0004). Based on current studies, whilst it is increased at the time of thrombosis, VEGF is not effective as a predictive biomarker of CAT.