Epithelioid hemangioendothelioma (EHE) is a rare vascular cancer in the lining of blood vessels, characterized by tumors that can occur anywhere in the body. While tumors are often slow-growing or dormant, some patients experience regression of the disease whereas others see a more rapid progression. Furthermore, it is a very unusual disease because the appearance of tumors in multiple body parts does not necessarily carry a poor outcome or indicate aggressive disease. Therefore, while EHE is usually considered a sarcoma (a form of cancer), it is very different from most cancers.

EHE is so rare that only 0.01 percent of the cancer population has it and it affects about 1 person in every 1,000,000 worldwide.  Around 20 cases are diagnosed in the US every year.

For more information, visit these sources for the information above:

http://www.cravatfoundation.org/newly-diagnosed

https://en.wikipedia.org/wiki/Epithelioid_hemangioendothelioma