It's not clear what causes a liver hemangioma to form. Doctors believe liver hemangioma is congenital — meaning that you're born with it.

Liver hemangioma usually occurs as a single abnormal collection of blood vessels that is less than about 1.5 inches (about 4 centimeters) wide. Occasionally liver hemangiomas can be larger or occur in multiples.

In most people, liver hemangioma will never grow and never cause any signs and symptoms. But in a small number of people, liver hemangioma will grow to cause complications and require treatment. It's not clear why this happens.

Aug. 13, 2013