Hepatic hemangioma is the most common benign tumor of the liver. Hepatic hemangioma is more common in women, with a male to female ratio of 1:5-10, and can occur at any age. Interventional treatment has become the main treatment method for hepatic hemangioma because of its wide indications, small trauma, fast recovery and good efficacy.
I. Etiology and pathology
The etiology of hepatic hemangioma is not yet clear, and is mostly thought to be related to congenital developmental abnormalities, which may be associated with the following factors.
① Deformation of capillary tissue after infection and capillary dilation.
②Vascular expansion after local necrosis of liver tissue to form a vacuolation. The blood vessels around the necrotic liver tissue are congested and expanded, and finally form a vacuolation.
③After regional blood circulation stagnation in the liver, resulting in the formation of spongy dilatation of blood vessels and persistent venous blood stagnation in the liver, leading to venous expansion.
④Vascular dilatation is formed after intrahepatic hemorrhage, hematoma mechanization, and vascular recanalization.
⑤ Abnormal development of blood vessels causes spongy dilatation of blood vessels, which is the most acceptable theory.
Hepatic hemangiomas vary in size, with small ones requiring microscopic diagnosis and large ones reaching the pelvis and weighing more than 18 kg, and are mostly larger than those seen clinically. They are often located in the right lobe and 90% are solitary. The tumor is purple-red or purple-blue in color, soft in texture, with clear boundaries and a reticulated cut surface. Hepatic hemangioma can be divided into 4 types.
(1) Hepatic cavernous hemangioma is the most common.
(2) Sclerosing hemangioma has collapsed or closed lumen with extremely rich fibrous tissue in the septum, and the hemangioma shows degenerative changes.
(3) Hepatic capillary hemangioma is rare, with narrow lumen and abundant septal fibrous tissue.
(4) Hemangioendothelial cell tumor is rare, between benign hepatic hemangioma and hepatic hemangioendothelial cell sarcoma.
Clinical manifestations
The clinical manifestations of hepatic hemangioma are related to the location, size, growth rate and the degree of liver parenchyma involvement of the tumor, while small ones are asymptomatic and large ones may have symptoms such as epigastric discomfort, abdominal distension, abdominal pain, decreased appetite, nausea and prolonged hypothermia.
Indications and contraindications of interventional treatment
Indications for hepatic artery embolization for hepatic hemangioma treatment: those with symptoms, those with hepatic hemangioma rupture and bleeding, those with masses larger than 5 cm in diameter, those with tumor tendency to increase or those with masses located under the liver envelope that may rupture under external force. Overall, regardless of the site, scope and number, there is no absolute contraindication to hepatic artery embolization for hepatic hemangioma, but it is used with caution in severe liver and kidney insufficiency.
Interventional treatment methods
The main blood supply of hepatic hemangioma comes from hepatic artery, and portal vein basically does not participate in blood supply (rarely seen as portal vein blood supply), which is the theoretical basis of hepatic artery embolization for hepatic hemangioma. The specific method of hepatic hemangioma intervention is to use percutaneous puncture, often by inserting a catheter into the hepatic artery from within the femoral artery. Hepatic arteriogram is performed first, and then according to the image, the blood supplying artery of hepatic hemangioma is confirmed, and the catheter is super-selectively inserted into the target vessel of the tumor and injected with appropriate amount of drugs and embolization agents to perform sclerotherapy. The commonly used embolic drugs include pinyamycin and iodinated oil emulsion, gelatin sponge, etc. After the operation, there may be hypothermia, local discomfort and nausea and other reactions, which can be restored to normal after 3 days.
V. Interventional treatment efficacy
Hepatic hemangioma mainly consists of blood-filled and enlarged hepatic blood sinuses. The embolic agent injected by interventional therapy enters and stays in these blood sinuses, causing the destruction of endothelial cells of hemangioma blood sinuses, thrombus formation and permanent occlusion of blood sinuses. The tumor will then shrink or disappear and will not rupture and bleed, achieving a therapeutic effect. We have successfully performed several cases of interventional treatment for hepatic cavernous hemangioma without a single complication, and the tumors all shrank significantly from 3 to 6 months after treatment, and about 40% of patients had their tumors completely disappeared after one year. In one female patient, the maximum diameter of hepatic hemangioma was 24 cm, and the abdomen was obviously enlarged, and the maximum diameter was 16 cm at 9 months after the first intervention, and the maximum diameter was 10 cm at 12 months after the second intervention, and the abdominal enlargement was nearly disappeared. Therefore, transhepatic artery embolization has become the main treatment method for hepatic hemangioma because it is less traumatic, faster recovery (usually about one week of hospitalization), lower cost than surgical operation, better efficacy and lower complications.