Incidence and clinical presentation

Angiosarcomas are rare (accounting for 2% of sarcomas), aggressive, vascular tumors that can arise in any part of the body but is more common in soft tissues. Angiosarcoma has an estimated incidence of 2 cases per 1 million people. In the United States, it affects approximately 600 people annually, who are typically aged 60 to 70 years.[19]

Angiosarcomas are extremely rare in children. It is unclear if the pathophysiology of angiosarcomas in children differs from that of angiosarcomas in adults. Cases have been reported in neonates and toddlers, with presentation of multiple cutaneous lesions and liver lesions, some of which are GLUT1 positive.[20-23] Most angiosarcomas involve the skin and superficial soft tissue, although the liver, spleen, and lung can be affected; bone is rarely affected.

Nomenclature of these liver lesions has been difficult and confusing with use of outdated terminology proposed in 1971 (e.g., type I hemangioendothelioma: infantile hemangioma; type II hemangioendothelioma: low-grade angiosarcoma; type III hemangioendothelioma: high-grade angiosarcoma).[21] A report of eight cases of liver angiosarcomas in children highlighted the misuse of the term hemangioendothelioma and the importance of early diagnosis and treatment of these tumors.[24]