The extra growth forms a complex mass (tumor). After birth, the cells can keep increasing and the mass can get bigger. A vascular tumor is a growth of vascular origin, formed from blood vessels. Some are benign and some are malignant. Vascular neoplasms are unusual and, as such, pose a diagnostic and treatment challenge to the vascular surgeon. rteriovenous hemangioma is a benign cutaneous vessel proliferation that presents as a red papule that can mimic other vascular tumors. Vascular malformations are no real tumors and can be divided into low- or high-flow lesions. The majority of vascular tumors have a slow growth rate, and the size of the tumor increases with age. Tumor secrets VEGF and attracts growth of vasculature towards it. In this tool we simulate a tumor (green) secreting vascular endothelial growth. The hemangiopericytoma is a tumour of the pericyte cells so it can occur in ... malignant vascular tumor, which includes 1% of vascular tumors. A vascular tumor is a tumor of vascular origin; a soft tissue growth that can be either benign or malignant, formed from blood vessels or lymph vessels. Examples of vascular tumors include hemangiomas, lymphangiomas, hemangioendotheliomas, Kaposi's sarcomas, angiosarcomas, and hemangioblastomas.