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Tufted angioma, kaposiform hemangioendothelioma, and the Kasabach-Merritt phenomenon

Denise Adams, MD
Ilona J Frieden, MD
Section Editor
Moise L Levy, MD
Deputy Editor
Rosamaria Corona, MD, DSc


Tufted angioma and kaposiform hemangioendothelioma (KHE) are rare vascular tumors that typically occur during infancy or early childhood. Tufted angioma, previously known as "angioblastoma of Nakagawa," is a benign tumor whose name derives from its histopathologic appearance characterized by tufts of capillaries within the dermis [1,2]. KHE is a locally aggressive tumor that may involve superficial and deep soft tissues and, rarely, the retroperitoneum, mediastinum, and internal organs [3,4].

Tufted angioma and KHE share several histopathologic and clinical features and are thought to be part of the same neoplastic spectrum [5,6]. The most serious complication of these tumors is the Kasabach-Merritt phenomenon, a life-threatening coagulopathy characterized by severe thrombocytopenia and consumption of fibrinogen and other coagulation factors [7].

Tufted angioma, KHE, and the Kasabach-Merritt phenomenon will be discussed in this topic. Infantile hemangiomas, congenital hemangiomas, venous malformations, capillary malformations and associated syndromes, and Klippel-Trenaunay syndrome are discussed separately.

(See "Infantile hemangiomas: Epidemiology, pathogenesis, clinical features, and complications".)

(See "Infantile hemangiomas: Evaluation and diagnosis".)

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Literature review current through: Oct 2017. | This topic last updated: Nov 13, 2017.
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