Kaposiform Hemangioendothelioma: Atypical Features and Risks of Kasabach-Merritt Phenomenon in 107 Referrals

Abstract

Objective To examine the presentation characteristics of patients with kaposiform hemangioendothelioma (KHE) to describe the spectrum of disease and risk factors for Kasabach-Merritt phenomenon (KMP). Study design Retrospective review of 163 patients referred to the Vascular Anomalies Center at Children’s Hospital Boston for KHE between 1991 and 2009 identified 107 patients with sufficient data for inclusion. Results The prevalence of KHE in Massachusetts is approximately 0.91/100,000 children. KHE manifested in infancy in 93% of cases; 60% as neonates. Common presenting features included enlarging cutaneous lesion (75%), thrombocytopenia (56%), and musculoskeletal pain or decreased function (23%). Cutaneous KHE favored the extremities, especially overlying joints. In our cohort 71% developed KMP (11% after initial presentation), and 11% of patients lacked cutaneous findings. Retroperitoneal and intrathoracic lesions, though less common, were complicated by KMP in 85% and 100% of cases, respectively. Compared with superficial lesions, KHE infiltrating into muscle or deeper was 6.3 fold more likely to manifest KMP, and 18-fold higher if retroperitoneal or intrathoracic. KHE limited to bone or presenting after infancy did not manifest KMP. Conclusion An enlarging lesion is the most common presenting feature of KHE in infancy. Older patients with KHE or those lacking cutaneous manifestations present with musculoskeletal complaints or atypical symptoms. The risk of KMP increases dramatically when tumor infiltrates muscle or when KHE arises in the retroperitoneum or mediastinum.

Clinical Review: Management of Adult Kasabach-Merritt Syndrome Associated with Hemangiomas

“…In terms of pediatric literature, TA and KHE are rare, with incidence of KHE estimated at 0.07/1000, 000 children per year [2,3]. The incidence of KMS in patients with KHE and TA are 70% and 10% respectively [4,5]. TA and KHE share several histopathologic similarities, while TA is a benign tumor characterized by tufts of capillaries within the dermis, [3,4] KHE tends to be locally aggressive tumor that may involve superficial or deep soft tissues [4,6].…”

“…TA and KHE share several histopathologic similarities, while TA is a benign tumor characterized by tufts of capillaries within the dermis, [3,4] KHE tends to be locally aggressive tumor that may involve superficial or deep soft tissues [4,6]. In the adult population, KMS is seen most often as a complication from hemangiomas [7], hemagiomatosis [4] or angiosarcoma [8].…”

A Diagnostic Program of Vascular Tumor and Vascular Malformations in Children According to Modern Classification

“…Both tumors are characterized by local aggressive growth and may be accompanied by a Kasabach-Merritt phenomenon, which is a coagulopathy, associated with severe thrombocytopenia and hypofibrinogenemia (12,13).…”

Beyond infections: tumors and malformations of the diaper area

“…8 Kasabach-Merritt phenomenon (KMP) may occur with either KHE or TA. KMP is a coagulopathy characterized by profound thrombocytopenia, hypofibrinogenemia, and anemia.…”