bubble_chart Overview

Liver hemangiomas (hemangiomas) are mostly cavernous hemangiomas, a common benign liver tumor that can occur at any age but often presents symptoms in adults, with a higher incidence in women. Liver hemangiomas are the most common benign tumors in the liver, and most cases can be diagnosed preoperatively. The vast majority are asymptomatic, though a few may cause discomfort in the liver area due to larger tumor size. If there is a tendency for growth or if the tumor is located beneath the liver capsule, there is a risk of massive bleeding, which can be life-threatening, necessitating early treatment. The tumors can appear anywhere in the liver, often beneath the capsule, and are mostly solitary (about 10% are multiple). The tumor diameter is usually less than 4 cm, but can range from a few millimeters to as large as 30 cm in rare cases. The tumor surface appears dark red or purple, with an outer capsule, and the cut surface shows a spongy texture. Sometimes, thrombosis and scarring may be seen within the hemangioma, with occasional calcification. Microscopically, the hemangioma consists of a network of interconnected vascular channels lined by flat endothelial cells of varying sizes, containing red blood cells, and occasionally fresh organizing thrombi. The tumor has a clear boundary with surrounding tissue.

bubble_chart Etiology

Liver blood vessel tumors are the most common benign tumors in the liver, accounting for 84% of all benign liver tumors, and are more frequently seen in older women. Most are cavernous hemangiomas, with capillary hemangiomas and hemangioendotheliomas being extremely rare. They are often associated with multiple pregnancies and the use of oral contraceptives. The lesions can be solitary or multiple, most commonly found in the posterior segment of the right lobe of the liver.

Pathological changes include the tumor being covered by a connective tissue membrane, clearly demarcated from the surrounding liver tissue, and composed of blood-filled vascular sacs separated by fibrous septa, with the sac walls lined by flattened endothelial cells. The tumor may undergo fibrosis, calcification, and thrombosis.

bubble_chart Clinical Manifestations

Small lesions are often asymptomatic and detected during routine ultrasound examinations, while larger lesions may cause upper abdominal discomfort or palpable masses. Giant hemangiomas can lead to significant liver enlargement. Clinically, lesions smaller than 4 cm are usually asymptomatic and often incidentally discovered during abdominal ultrasound examinations. About 40% of lesions larger than 4 cm are associated with symptoms such as abdominal discomfort, hepatomegaly, loss of appetite, and indigestion. Liver hemangiomas often contain organized thrombi, and recurrent thrombosis may cause tumor swelling, leading to stretching pain due to Glisson's capsule distension. The masses vary in texture, with varying degrees of compressibility, and a few may feel like hard nodules. Spontaneous rupture of the masses is rare. Liver function is generally normal. A rare syndrome associated with large hemangiomas is consumptive coagulopathy, thrombocytopenia, and hypofibrinogenemia.