They are characterized by growing and subsequent disappearing phases leading to spontaneous regression in most cases. These lesions occur three times more often in girls than in boys. The reason for this remains unclear. Sometimes these lesions occur in families.
Superficial hemangiomas are the most common of the three types.
Although the exact cause of hemangiomas is poorly understood, the natural course of these lesions is well-documented. Often they are absent at birth, but appear within the first few weeks of life. The initial lesion may be a flat red or white spot, which usually has visible tiny blood vessels in the center. During the first six months of life, the lesion grows at a very rapid rate. Parents are often alarmed at how fast these lesions can grow.