<unk>  develops when damage to the DNA of endothelial cells causes them to divide uncontrollably and prevents programmed death. This allows them to grow into a mass invading other parts of the body and consuming its resources. If part of the mass breaks off and enters the circulatory or lymphatic system (which is very common due to<unk> s arising from the lining of said systems) it allows them to lodge elsewhere in the body. This process is called metastasis and is a negative prognostic factor. The underlying causes of DNA damage is not understood but several risk factors are widely accepted. Accepted risk factors include lymphedema, radiation therapy, neurofibromatosis, Maffucci syndrome, Klippel-Trenaunay syndrome and chemicals such as arsenic, thorotrast and vinyl chloride. A 2020 study analyzing the genome of cutaneous<unk> s suggests that ultraviolet radiation may be a causative agent of<unk> s. Immunosuppression may play a role in the pathogenesis of<unk> . There have been reports of<unk>  in immunosuppressed individuals following kidney transplantation. The association between lymphedema and<unk>  may be due to localized immunodeficiency, however this hypothesis has not been confirmed. Some studies suggest a link between AIDS and<unk>  though this may be due to misdiagnosed Kaposi's sarcoma.
Angiosarcoma
Hemangiosarcoma
Glomangiosarcoma
Hemangioma
Angiokeratoma
Lymphangiosarcoma
Sarcoma
Lymphangioma