The word hemangioma comes from the Latin words hemangio meaning blood vessel and oma meaning tumor with active cell dividing activity. Hemangiomas differ from other vascular birthmarks in that they are biologically active, their growth is dependent from the growth of the child. They are the most common benign tumor of infants. Hemangioma growth is referred to as Hyperplasia , where as other vascular birthmarks growth is referred to as Hypertrophy .
Most hemangiomas appear within a week or two after birth.
Hemangiomas are up to 5 times more common in girls than boys. They are less likely to occur in African American babies then Caucasian babies. They occur more frequently in premature infants. Children can develop a single lesion or they can have a dominant primary lesion with smaller associated hemangiomas. There can be an internal lesion with no associated lesions on the outside.