Epithelioid hemangioendothelioma is a rare form of cancer that occurs in the thin layer of cells, or endothelium, that line the blood vessels of the human body — specifically in the liver and lungs. Is it named after its classification between angiosarcoma and hemangioma, which are also vascular tumors comprising endothelial cells. Epithelioid hemangioendothelioma is also known by several other terms, which include angioendothelioma, cellular hemangioma, low-grade anaplastic angiosarcoma and histiocytoid hemangioma. It is so rare that it only appears in 0.01 percent of the world's cancer-stricken population, and accounts for only 1 percent of abnormal vascular tissue masses.
A pair of medical researchers first described epithelioid hemangioendothelioma in 1975, including confirming its vascular nature. At the time, it was called an "intravascular bronchioloalveolar tumor." The most famous case of the disease occurred in 2003, when photographer and actress Kris Carr received an epithelioid hemangioendothelioma diagnosis. The cause of this tumor remains unknown.
Epithelioid hemangioendothelioma is classified as a highly aggressive form of cancer. It has the capability of spreading, or metastasizing, to the lung and the bones. The disease is more common in males than in females, and it particularly affects people in their 20s and 30s.
People with epithelioid hemangioendothelioma often experience pain and swelling at the affected areas. Tumors at the spinal cord can lead to paraplegia — a physical impairment of the legs — in the most extreme cases. The disease can be diagnosed using radiological images, usually X-rays. Other diagnostic medical imaging methods, such as computed tomography (CT) scans or magnetic resonance imaging (MRI) scans, are insufficient for diagnosing epithelioid hemangioendothelioma because, unlike X-rays, they fail to distinguish the tumor from other types of cancers.
Treatment of epithelioid hemangioendothelioma varies, as it largely depends on the severity of the tumor. Physicians usually treat less aggressive cases with curettage, which is the act of removing tissue via scraping with a surgical instrument called a curette. A wider section for curettage is required for more severe cases. Although physicians do suggest or carry out amputation for the worst instances of the disease, resorting to such an extreme form of treatment is exceedingly rare.
The medical community remains undecided on how effective more popular treatments for cancer, such as chemotherapy and radiation, are for epithelioid hemangioendothelioma, as the tumor typically does not respond to such methods. Additionally, prognosis is still not well defined due to the rarity of the disease. Physicians generally predict a good outcome after conclusion of treatment, though recurrence is always a possibility, however, and some studies have shown only up to 10 months of survival after diagnosis.