CLASSIFICATIONS OF HEMANGIOENDOTHELIOMA
The term "hemangioendothelioma" has been used to designate various groups of vascular tumors. There are many different subtypes:
retiform (RKE)
Retiform pattern of proliferating vessels with intraluminal papillae and hyaline cores. Histologically similar to those seen in Dabska tumor.
epithelioid hemangioendothelioma (EHE)
Having epithelial-like cells lining the vascular channels and can occur simultaneously at multiple sites
kaposiform hemangioendothelioma (KHE)
Which is a locally invasive tumor, occuring in young children and having no capacity to metastasize.
spindle cell hemangioendothlioma (SCHE)
Has spindle cells, smooth muscle cells normally supporting the vessels.
angiolymphoid
Malignant endovascular papillary angioendothelioma, also known as a Dabska tumor, a. low-grade angiosarcoma that can affect the skin of children.
Each of these clinical entities has its own typical pattern of progression and of associated symptoms, and it is unclear whether they represent a different disease or a spectrum of related disorders. Unfortunately, the term hemangioendothelioma is often used erroneously, and the multiplicity of terms may be reflective of the great confusion that exists about the terminology. Other forms of hemangioendothelioma have recently been noted, ie:
Composite
Polymorphous
Sometimes, it may be hard to make a correct distinction between these and other rare vascular conditions.
Below is an extract from an article which refers to the importance of a rare disease registry in general and specifically for EHE:
“Due to the rarity of this disease, double-blind randomized controlled studies investigating various management strategies will not be possible. Clinical registries such as the Armed Forces Institute of Pathology Registry and the InternationalHemangioendothelioma, Epithelioid Hemangioendothelioma and Vascular Disorders Registry are places where physicians as well as patients and their families can share their symptoms and treatments, along with response rates and relapses. Such registries may help both patients and physicians alike in following the natural history of the disease and its response to different therapeutic regimens.”