Cavernous hemangioma of the liver

　　The exact etiology of cavernous hemangioma of the liver is unknown, and there are several theories:

　　1. Developmental abnormality theory

　　It is generally believed that during the process of embryonic development, due to abnormal vascular development, tumor-like proliferation occurs, forming cavernous hemangiomas. Some are present at birth or can be seen shortly after birth, which also indicates congenital developmental abnormalities.

　　2. Other theories

　　After infection and deformation of capillary tissue, capillary dilation occurs; after local necrosis of liver tissue, vascular dilation forms vesicular structures, with surrounding blood vessels becoming congested and dilated; regional blood circulation stasis within the liver leads to the formation of cavernous dilatation of blood vessels; after bleeding within the liver, the blood clot becomes organized, blood vessels are re-established, and vascular dilation occurs.

　　Rupture and bleeding of cavernous hemangioma of the liver can cause severe upper abdominal pain, as well as symptoms of hemorrhage and shock; when a pedunculated tumor grows freely outside the liver and twists, tumor necrosis can occur, leading to abdominal pain, fever, and collapse. There are also individual cases where, due to the large size of the hemangioma and the formation of arteriovenous fistula, the increased return blood volume and increased cardiac burden can lead to heart failure and death.

　　The cavernous hemangioma of the liver grows slowly, with a long course of disease, and the medical history can date back many years ago. It is classified according to clinical manifestations as follows:

　　1. Asymptomatic type

　　This type accounts for the majority (more than 80%), has no sensation throughout life, and is often discovered unexpectedly during routine health check-ups or abdominal surgery.

　　2. Symptomatic type

　　Symptoms may occur when the tumor diameter exceeds 4cm or more, common symptoms include:

　　(1) Abdominal mass: More than half of the patients have this sign, the mass has a cystic feeling, is painless, the surface is smooth or not smooth, softness and hardness are inconsistent, it moves up and down with respiration, and in some cases, vascular bruits can be heard by auscultation over the mass.

　　(2) Gastrointestinal symptoms: Right upper quadrant pain and discomfort, as well as loss of appetite, nausea, vomiting, belching, postprandial bloating, and dyspepsia may occur.

　　(3) Compression symptoms: Compression of the lower esophagus can cause difficulty in swallowing; compression of extrahepatic bile ducts can cause obstructive jaundice and cholecystasis; compression of the portal venous system can cause splenomegaly and ascites; compression of the lungs can cause dyspnea and atelectasis; compression of the stomach and duodenum can cause gastrointestinal symptoms, etc.

　　The diagnosis of cavernous hemangioma of the liver is generally not difficult. The vast majority can be diagnosed without symptoms, without a history of hepatitis, AFP (-), and confirmed by combining two or more typical imaging findings.

　　Cavernous hemangioma of the liver is the most common benign liver tumor. It may be related to congenital developmental abnormalities, therefore, preventive measures should include attention to hygiene and diet during pregnancy, careful diet, taking medication as prescribed by a doctor, eating more fresh vegetables and fruits, and ensuring the healthy growth of the fetus.

　　Laboratory tests for cavernous hemangioma of the liver are not very helpful for diagnosis. Generally, liver function is normal, enzyme activity is not high, and a few patients have decreased red and white blood cells and platelets. Recovery can be achieved after resection of the hemangioma. Hematological changes are more common in cases of giant cavernous hemangioma of the liver. The diagnosis of cavernous hemangioma of the liver mainly depends on imaging examinations:

　　1. Ultrasound examination

　　About 70% of hemangiomas show strong echoes, with uniform internal echoes, while the rest may show low echoes, isoechogenicity, or mixed echoes. If calcification is present, strong echoes are accompanied by acoustic shadows. Color Doppler ultrasound examination shows that blood flow signals within hemangiomas are rare, and some hemangiomas may appear with a central blood pool-like filling.

　　2. CT scan

　　Cavernous hemangioma CT scan shows low density, with uniform density, and in large hemangioma lesions, there is a lower density area in the center, which is star-shaped, cleft-like, or irregular. Occasionally, calcification can be seen within the tumor, presenting as circular or irregular strong echoes. The edge of the lesion is usually clear and smooth. In typical cases, the enhancement scan shows early enhancement of the lesion edge with high density, followed by progressive expansion of the enhanced area towards the center. Delayed scanning shows isodense filling of the lesion, displaying a 'fast in and slow out' phenomenon. Hemangiomas with a diameter less than 3cm show more complex enhancement patterns, which may include: early high-density enhancement of the lesion, some lesions may not be significantly enhanced, lower than normal liver tissue, delayed scanning shows isodense filling of all lesions, and in some cases, there is no enhancement at all, and there is no filling in the delayed scan. Such hemangiomas have very thick walls, narrow lumens, and it is difficult for contrast medium to enter.

　　3. Radionuclide liver blood pool scanning

　　Radionuclide liver blood pool scanning has high diagnostic value for cavernous hemangioma of the liver. Using 99mTc-labeled red blood cells, imaging can be performed where there is blood flow. Radioactive accumulation occurs in areas with rich or stagnant blood flow. Cavernous hemangioma of the liver is characterized by radioactive accumulation at the site of the tumor starting at 5 minutes, gradually becoming more concentrated, and still not dissipating after 1 hour. This phenomenon of slow radioactive over-filling is a characteristic basis for diagnosing cavernous hemangioma of the liver.

　　4. MRI examination

　　MRI examination shows long T1 and long T2 signals, with T2 images showing relatively high signals,呈 'light bulb sign'.

　　5. Hepatic angiography

　　Hepatic angiography is an invasive examination method with high sensitivity and specificity for cavernous hemangioma. After early injection of contrast agent, the surrounding area of the lesion is stained within 2-3 seconds, and the contrast agent is cleared slowly, can fill for more than 18 seconds. This phenomenon of fast entry and slow exit of the contrast agent is a typical feature of cavernous hemangioma, known as the 'early departure and late return sign'.

　　Attention should be paid to dietary adjustment before and after surgery for patients with cavernous hemangioma of the liver, which is conducive to physical recovery.

　　1) Avoid spicy foods, as spicy foods can stimulate the gastrointestinal tract, increasing the workload of blood vessels. Malnutrition and malnutrition are common in patients with cavernous hemangioma. Therefore, enhancing appetite and strengthening nutrition is very important for the recovery of tumor patients.

　　2) Diversify your diet, eat more high-protein, high-vitamin, low-animal-fat, easily digestible foods, and fresh fruits and vegetables. Avoid eating stale, deteriorated, or刺激性 foods, eat less smoked, roasted, pickled, fried, or salty foods. Mix coarse and fine grains in staple foods to ensure nutritional balance.

　　3) Vegetables, fruits, and beans are rich in a variety of vitamins and trace elements, and have certain anti-cancer and anti-tumor effects. For example, soybeans, cabbage, and Chinese cabbage are rich in molybdenum, tomatoes, carrots, amaranth, and jujube are rich in vitamin A, C, and B vitamins, among which amaranth has the best nutrition, containing a variety of vitamins, several times more than tomatoes.

　　The treatment of cavernous hemangioma of the liver depends on the size, location, and growth rate of the tumor. For those with cavernous hemangioma with a diameter less than 5cm and without any clinical symptoms, growing within the liver parenchyma, no special treatment is required. They can be followed up at the outpatient department, observed for changes in the tumor through ultrasound, and undergo surgical treatment if there is significant enlargement; while for those with a diameter greater than 5cm or with clinical symptoms, due to the increased size of the tumor, there may be compressive symptoms on surrounding organs and adverse effects on the cardiovascular system, or even rupture of the tumor that may threaten life, effective treatment should be carried out. Currently, the main treatment methods for liver cavernous hemangioma include hepatectomy, tumor ligation, hepatic artery ligation, hepatic artery embolization, cryotherapy, microwave coagulation, intratumoral sclerosing agent injection, and radiotherapy, etc.

　　1. Liver lobectomy

　　Liver lobectomy is still the best method for the treatment of hemangiomas at present. However, due to the rich blood supply of hemangiomas, bleeding during surgery is extremely easy, especially for large cavernous liver hemangiomas. Since the tumor compresses adjacent organs, local anatomical relationships shift, making the surgery more difficult. Therefore, strict control of surgical indications is necessary. For solitary hemangiomas, especially those located at the periphery of the liver or those localized to one side of the liver, liver local resection, lobectomy, or hemihepatectomy can be performed; if the extent of the lesion has exceeded half of the liver, the remaining liver is significantly hyperplastic, and there is no liver cirrhosis, with normal liver function, a trisectional liver resection can be performed. For lesions that have involved the first and second hepatic gates or are widespread, compressing adjacent organs and causing symptoms, the main lesion or the liver lobe or segment compressing adjacent organs should be resected as much as possible, and the small remaining tumor can be treated with hemangioma ligation or radiotherapy. The main problem in the treatment of liver hemangiomas with lobectomy is how to control bleeding during surgery. Especially for large cavernous liver hemangiomas, due to the rich blood supply, large tumor size, anatomical displacement, and the tumor itself being prone to bleeding, this increases the difficulty of surgery and may cause massive bleeding that is difficult to control during surgery. Therefore, how to control bleeding during liver lobectomy for cavernous liver hemangiomas is the key to surgical success. Summarizing the experience from 683 surgeries, the following points should be paid attention to during liver resection for hemangiomas:

　　(1)Fully expose the tumor. Generally, a diagonal incision under the costal margin is made. If the tumor is located in the right half of the liver, the incision can extend from the xiphoid process along the right costal margin to the 12th rib on the right; if the tumor is located in the left half of the liver, it is difficult to expose due to the limited space, and a double costal margin 'man' shape incision can be adopted, which can fully expose the tumor and facilitate operation; for large liver vascular hamartomas that require right trisection resection, a thoracoabdominal combined incision can be made if necessary.

　　(2)Fully mobilize the liver, and before separating the tumor and resecting the liver, it is advisable to ligate the affected liver artery first to shrink and soften the tumor, which is beneficial for surgical manipulation. It is usually adopted to place a rubber tube at the ligamentum hepatoduodenale first to block the blood flow into the liver, which is more convenient for separating and resecting the tumor, and can also prevent massive bleeding during the surgical process. Before resecting the liver, the surrounding ligaments and adhesions of the tumor should be carefully separated, cut, and ligated, so that the tumor and the affected liver can be fully mobilized. The degree of mobilization should reach the point where the surgeon can hold the liver cutting line with their hands and control the bleeding from the liver incision as a principle. For large vascular hamartomas in the right liver that have reached the anterior wall of the inferior vena cava behind the liver, after fully mobilizing the right liver, the liver can be flipped to the left side, carefully separated, and the short hepatic veins in front of the inferior vena cava can be ligated one by one to prevent the anterior wall of the inferior vena cava from being torn or the short hepatic veins from being pulled off during liver resection.

　　(3) Liver resection should be performed after blocking the hepatic portal at normal temperature, with each block time of 15-20 minutes. If the tumor cannot be cut off in one block, relax for 3-5 minutes after the first block, and then perform the second block, until the tumor is cut off. If possible, selective blocking of the hepatic portal of the affected side of the liver can be chosen, which can extend the blocking time.

　　(4) The selection of the liver incision line should be biased or close to the normal liver tissue. Use vascular forceps to clamp and cut and ligate all the断面 blood vessels and bile ducts while cutting. Until the tumor is completely resected. For multiple hemangiomas or hemangioma lesions with extensive lesions, those who need local or main tumor resection should pay attention to the incision line as close as possible to the normal liver tissue, otherwise it is easy to cause massive bleeding; it is forbidden to cut or ligate on the tumor body, in order to avoid uncontrolled oozing; after the main tumor is resected, small hemangiomas can be treated with ligation.

　　(5) After tumor resection, the liver wound should be thoroughly stopped bleeding. Active bleeding can be sutured in an '8' shape. After there is no obvious bleeding, a piece of free omentum can be used to cover the liver wound and suture it, or the liver wound can be sutured together. The rough surface of the retroperitoneum is sutured for hemostasis, and a double lumen tube is placed under the diaphragm for continuous negative pressure aspiration.

　　(6) When excising a large hepatic cavernous hemangioma, a central venous catheter should also be placed from the external jugular vein or internal jugular vein or great saphenous vein to the vicinity of the right atrium before surgery, for the purpose of infusion or blood transfusion or measurement of central venous pressure during surgery. Since the tumor body can compress the inferior vena cava, causing poor venous return, all infusion and blood transfusion should be performed in the upper limb, and it is routine to expose one side of the radial artery, so that emergency arterial blood transfusion can be performed in case of massive bleeding, thereby improving the safety of surgery.

　　2. Hemangioma Ligation

　　For hemangiomas with a diameter below 15cm, multiple small hemangiomas, or scattered small hemangiomas in other liver lobes after the excision of the main tumor, hemangioma ligation can be adopted. When treating with hemangioma ligation, it is also necessary to pre-place a hepatic portal occlusion tube. After cutting the perihepatic ligaments, the hemangioma should be fully freed, then block the first hepatic portal to further reduce the size of the hemangioma. Then, gently press the tumor body with fingers, use a large curved needle, and 7 or 10 silk thread to puncture from the normal liver tissue near the hemangioma, and pass through the base of the tumor, then puncture out from the other side of the normal liver tissue of the tumor, do not tie it temporarily, according to the size of the hemangioma, use the same method to suture intermittently or in an '8' shape (needle spacing 1-1.5cm), suture the entire tumor body, and then tighten and tie each knot one by one. When ligating, attention should be paid to not passing the needle through the tumor body, in order to avoid massive bleeding from the needle hole after the hepatic portal occlusion is relaxed. This method can effectively achieve the purpose of controlling the growth of hemangiomas.

　　3. Liver arterial ligation and liver arterial embolization

　　For multiple hemangiomas or lesions with a large range that have invaded most of the liver tissue or are adjacent to large blood vessels and cannot be resected, liver arterial ligation or embolization can be performed, and liver right, liver left, or intrinsic artery ligation can be performed according to the range of the lesion. After ligation, most of the tumors can become soft and shrink, and this method is very satisfactory for cystic hemangiomas. Based on the tumor shrinkage, the addition of radiotherapy after surgery can promote tumor organization and hardening, which has a certain effect on improving symptoms and controlling tumor growth.

　　In recent years, with the development of interventional radiology technology, for patients diagnosed with cavernous hemangioma of the liver and with a low possibility of surgical resection, liver arterial embolization can be performed via the femoral artery to achieve the purpose of controlling the development of the hemangioma. Common embolic agents include iodine oil, microspheres (albumin microspheres, gelatin microspheres, and ethyl cellulose microspheres, etc.), absorbable gelatin sponge, etc., and permanent embolization can also be performed with memory alloy steel rings. Liver left or right artery embolization can be performed according to the range of the lesion, usually without adverse reactions, and most patients can see tumor shrinkage after surgery.

　　4. Freezing therapy

　　For cavernous hemangiomas of the liver that cannot be surgically resected or arterial ligation performed, and for those who have failed liver arterial embolization via the femoral artery, freezing therapy can be used after portal occlusion, and the tumor has softened and shrunk. Generally, liquid nitrogen is used, with the lowest temperature reaching -196°C. There are roughly three methods of freezing:

　　① Contact freezing: Place the freezing head on the tissue surface and apply pressure to freeze, which can produce a hemispherical frozen block, with the freezing depth approximately equal to the radius of the frozen area;

　　② Insertion freezing: Use a needle-shaped freezing head to insert into the hemangioma to achieve treatment at a deeper level;

　　③ Direct liquid nitrogen spray freezing: Suitable for superficial diffuse superficial lesions with a large surface area. The freezing time depends on the freezing method, the size and depth of the lesion. Generally, 15 minutes of freezing can reach 80% to 90% of the maximum freezing effect, so a single freezing of 15 to 30 minutes is usually used. In the process of rapid freezing and slow natural dissolution, it can produce a coagulative necrosis in the frozen area. Two thermocouple needles can be used during surgery to monitor the temperature of the frozen area and the peripheral liver tissue. Freezing once under portal occlusion is equivalent to 2 to 3 times of freezing without portal occlusion. ALT may have a transient increase after surgery, which usually returns to normal within 1 to 2 weeks. There is a risk of rupture and bile leakage after freezing of the gallbladder and the first and second order bile ducts, so this method is not suitable for hemangiomas located at the porta hepatis.

　　5. Microwave fixation surgery

　　For large hemangiomas that cannot expose the porta hepatis or the first and second porta hepatis due to invasion, and for those with a large scope that cannot undergo tumor resection, microwave fixation can be used. For those with a large tumor mass that hinders the exposure of the porta hepatis, microwave fixation can be performed first to significantly reduce the tumor size before tumor resection. For those who cannot be resected, simple microwave high-temperature fixation treatment can also achieve a relatively satisfactory therapeutic effect.

　　Among 1120 patients, 23 cases of giant hepatic cavernous hemangiomas were treated with microwave coagulation, with the largest tumor diameter being 26 cm. After固化 treatment, the diameter of all tumors can be reduced by 70% to 90%, relieving compression symptoms, and significantly alleviating the pain of patients. Among them, 2 cases underwent surgical resection of the reduced hemangioma at 3 months and 20 months after surgery, respectively, and the resected specimens showed that the hemangioma had completely fibroticized.

　　6. Intra-tumor sclerosing agent injection

　　The most commonly used method is the sodium laurate injection into the tumor under the guidance of B-ultrasound. For a small number of patients with serious cardiovascular or respiratory system diseases who are not suitable for surgical treatment, this method can be used. Other commonly used sclerosing agents include psyllium, alum, and colloidal 32P, etc. However, this treatment method is difficult to achieve ideal results for large hepatic cavernous hemangiomas due to their large size, rich blood supply, and difficulty in obtaining ideal results.

　　7. Radiotherapy

　　The therapeutic effect of simple radiotherapy is often unsatisfactory, and it is generally used as adjuvant treatment after ligation or embolization of the hepatic artery, or radiotherapy is performed when there is still a small amount of residual hemangioma tissue after the main tumor is resected during surgery. In surgery, silver clips can be used to localize the residual hemangioma tissue, and small-field radiotherapy can be performed after surgery, which has a good effect. For those who receive simple radiotherapy, there is often liver function damage, and the prognosis is poor.

　　8. Management of hepatic cavernous hemangioma in special cases

　　(1) Hepatic hemangioma is accidentally found during other abdominal surgeries, at this time, both the location and size of the hemangioma and the complexity and contamination of the original surgery need to be considered. If the hemangioma is located at the lower edge of the liver or the left lateral lobe, it is not large, easy to remove and treat, and the original surgery is cholecystectomy or subtotal gastrectomy, etc., it can be considered to resect the hemangioma at the same time; on the contrary, if stomach, duodenal perforation or colectomy and other surgeries with severe contamination, it is not advisable to perform hemangioma resection at the same time, and it is better to perform hemangioma resection at a later time.

　　(2) Hepatic hemangioma during pregnancy: Women who were originally diagnosed or have been diagnosed with a large hepatic cavernous hemangioma, the hemangioma develops rapidly during pregnancy and has a risk of rupture, so it is best to perform hemangioma resection and terminate pregnancy within the first three months of pregnancy. If pregnancy has exceeded 8 months, in order to prevent hemangioma rupture during the delivery process, it is also necessary to take hemangioma resection as soon as possible.