Talk:Proliferating angioendotheliomatosis

Article categorization
This article was categorized based on scheme outlined at WP:DERM. kilbad (talk) 02:53, 27 December 2008 (UTC)

Quote from Andrews'
"Diseases designated "angioendotheliomatosis" have historically been divided into two groups: a reactive, involuting type and a malignant, rapidly fatal type. "Malignant angioendotheliomatosis" has been shown to be "intravascular (angiotropic) lymphoma," rather than a true vascular lesion.

The reactive type of angioendotheliomatosis is uncommon. It occurs in patients who have subacute bacterial endocarditis, Chagas' disease, pulmonary tuberculosis, cryoproteinemia, severe atherosclerotic disease, and antiphosphalipid antibodies, as well as in patients with no identifiable underlying process. They present with red-purple patches, plaques, nodules, petechiae, and ecchymoses, usually of the lower extremities. Some patients may present with a livedoid pattern or lesion resembling atrophie blache. Diffuse dermal angiomatosis is a variant associated with atherosclerosis. The lesion occurs most often on the thigh areas of vascular insuffiency and clears with revascularization. It has been described in association with an ateriovebous fistula and with anticardiolipin antibodies.

Histologically, the vessels in benign reactive angioendotheliomatosis are dilated and are filled with proliferating endothelial cells, usually without atypia. Some cases demonstrate a proliferation of capillaries in the dermis, with diffuse, lobular, or mixed patterns. Fibrin microthrombi are common, and some cases show amyloid deposits or positive immunohistochemical staining for human herpesvirus (HHV)-8 in lesional endothelial nuclei. The course in this type is characterized by involution over 1 to 2 years. Therapy for the underlying condition has been considered to hasten involution.

The malignant type of "angioendotheliomatosis" is actually a large-cell intravacular lymphoma. It is a rapidly progressive disease: usually death ensues within 10 months of diagnosis. The mean age at onset is 55 years. Reddish-purple plaques, nodules, or patches develop in the skin. Multisystem involvement is characteristic, with the CNS often involved. There may be progressive dementia or focal signs that reflect ischemic infarcts. Kidney, heart, lung, and gastrointestinal lesions may occur. Biopsy will show a proliferation of atypical cells that fill the lumen of cutaneous vessels. Immunochemical stains for leukocyte/common antigen have confirmed the lymphomatous nature of these cells. Angioendotheliomatosis is usually B-cell in phenotype, but cases of T-cell lineage have been reported. Some organs may show deffuse large cell lymphoma.

Doxorubicin alone, as well as in combination with vincristine, prednisone, and cyclophosphamide, has been effective in isolated cases. Rituximab has also been useful in CD20+ B-cell intravascular lymphoma."