Medical management of tumors associated with Kasabach-Merritt phenomenon: an expert survey.

Kasabach-Merritt phenomenon (KMP) is a rare consumptive coagulopathy characterized by profound thrombocytopenia and hypofibrinogenemia occurring in association with the vascular tumors kaposiform hemangioendothelioma (KHE) and tufted angioma (TA). Treatment remains challenging without consensus on the optimal medical management. The authors compiled expert opinions regarding management to establish treatment recommendations. Twenty-seven vascular anomalies centers in the United States and Canada were surveyed using 2 representative cases of KHE/TA with and without KMP. Overall response rate was 92% (25/27) with 88% completion (24/27). Most sites (23/25; 92%) do not have a standard of practice for management. The most frequent initial therapy for KHE+KMP was a combination of systemic corticosteroids and vincristine (VCR) (12/24 centers; 50%) followed by corticosteroids alone (29%). Second-line treatments were VCR (38%), rapamycin (21%), and propranolol (21%). Management of KHE/TA without KMP was variable; initial treatments included systemic corticosteroids (8/24; 33%) alone or with VCR (9/24; 38%), monitoring without medication (33%), VCR (8%), propranolol (8%), aspirin (4%), and rapamycin (4%). This survey highlights certain trends in the management of KMP-associated tumors, without standard protocols and consensus.