Treatment of hemangiomatosis with recombinant interferon alfa.

Hemangiomas and lymphangiomas are two main types of angiomatous disease that occur most commonly in infancy and childhood. Most hemangiomas resolve spontaneously, but some endanger vital structures such as the lung, as in pulmonary hemangiomatosis, a rare and universally fatal disease. Occasionally, hemangiomatous lesions are associated with thrombocytopenia, consumptive coagulopathy (Kasabach-Merritt syndrome), and microangiopathic hemolytic anemia. In the past, treatment of hemangiomatosis has included corticosteroids, cytotoxic drugs, laser therapy, embolization or other surgical approaches, radiation therapy, cryotherapy, and supportive measures such as the administration of platelets or clotting factors. Recently, it has been found that recombinant interferon alfa is effective in treating pulmonary hemangiomatosis, as well as other variants of hemangiomatous disease such as hemangioendotheliomas. Possible mechanisms of action for interferon include inhibiting proliferation of endothelial cells, smooth muscle cells, or fibroblasts that have been stimulated by endothelial cell or fibroblast growth factors; enhancing the production of endothelial prostacyclin; or decreasing the production of collagen. It is also possible that interferon alfa antagonizes angiogenesis indirectly through its immunostimulatory actions. With the exception of significant hemodynamic changes in some patients during the first 48 to 72 hours of therapy with interferon, side effects are relatively mild.