The VEGFA protein is involved in vascular permeability, angiogenesis, cell migration, and inhibition of apoptosis. In addition, binding of VEGFA to its receptors acti-vates the RAS/MEK/MAPK pathway, thus, leading to mitotic activation. Amplification of the VEGFA gene locus was found in several types of malignancy, such as osteosarcoma, hepatocellular carcinoma (HCC), and colorectal cancers. In patients with osteosarcoma, VEGFA gene amplification results in elevated expression of VEGFA and is associated with adverse tumor-free survival. VEGFA amplifications occur in 3-6 % of colorectal cancers and result in a highly aggressive disease. HCC patients with VEGFA gain responded better to sorafenib, a multi-kinase inhibitor that blocks, i.a., receptors of the VEGFA protein, resulting in improved survival of the patients. This suggests that VEGFA is a potential biomarker for response to sorafenib therapy in HCC. Hence, detection of VEGFA amplifications by Fluorescence in situ Hybridization may help in selecting patients eligible for an anti-VEGFA therapy.