Hemangiomas are benign tumors originating from endothelial cells that form the inner layer of blood vessels in our body. Structurally, they are consisted of pink-violet spaces filled with blood. Hemangiomas are divided into two groups as capillary and cavernous. In capillary hemangiomas, the spaces filled with blood are small and the appearance is more similar to strawberries. Most of the capillary hemangiomas occur at birth, they grow rapidly in the first 1-2 years and then 90% disappear spontaneously until the age of 2-3 years. Therefore, in babies with capillary hemangioma, it should be waited for at least 3 years if possible before any treatment is performed.
In cavernous hemangiomas, blood-filled cavities are larger and in these cavities there is a very slow flow of venous blood. Cavernous hemangiomas are also called venous malformations. Unlike capillary hemangiomas, they do not disappear from their own, even with age. Cavernous hemangiomas can be seen all over the body, but they are most commonly located in the liver, spine bones and limbs.
Cavernous hemangiomas may cause some complaints according to their location. In the liver they can cause pain and rarely bleeding. In the spine, they may cause pain, sometimes weaken the spine and cause fractures. The cavernous hemangiomas in the arm and leg are presented most commonly with pain and swelling. If cavernous hemangiomas grow or cause complaints, they need to be treated.
What are the methods of non-surgical treatment in hemangiomas?
The classical treatment method in hemangiomas is surgical operation. Surgical treatment is quite easy and suitable in some types of hemangiomas. However, operation is particularly risky in liver hemangiomas and spinal hemangiomas. In these regions, non-surgical treatments should be preferred whenever possible. The cavernous hemangiomas in the arm and leg can sometimes be deep, located in muscles and extensive. In such hemangiomas, surgery is also troublesome and, if possible, other treatment modalities should be preferred. Non-surgical treatment of common types of cavernous hemangiomas include:
In this treatment, first an angiography of the liver is performed from the groin artery, and the feeding vessels of the hemangiomas are identified. Then, an oily substance that tend to accumulate in hemangiomas, is mixed with a drug that destroys the hemangioma. This mixture is then injected into the arteries supplying the hemangioma. In this way, both the feeding vessels are clogged and the drug remains in the hemangioma for a long time (weeks) causing the mass to shrink gradually but markedly. If necessary, the process can be repeated in 1-2 years to allow the mass to become further smaller.
b. Percutaneous ablation:
Percutaneous ablation is the destruction of a tumor in our body by heating or freezing it with special needles, or giving high electrical current in short pulses. The preferred method of percutaneous ablation in hemangiomas is "heating" treatments such as microwave, laser and radiofrequency as well as "freezing" such as cryoablation. These treatments are performed under local anesthesia and mild sedation with a needle placed in the hemangioma from the skin. Each region of the needle and hemangioma is destroyed, and after months of treatment, a significant size reduction in hemangioma occurs. Percutaneous ablation can also be repeated if necessary to reduce the mass further.
Both chemoembolization and percutaneous ablation reduce the size of hemangiomas and relieve pain, pressure, and lower the risk of bleeding. In some patients, it may be necessary to apply both treatment modalities. The decision to use which technique in which patient must be made by physicians experienced in interventional oncology. Common types of hemangiomas and their non-surgical treatment methods are described below.
Liver hemangiomas are common and the majority are small. Ultrasonography, CT and MRI findings are usually very typical and diagnosis can be generally made without a biopsy. Sometimes, however, hemangiomas may be confused with cancer, and in this case, the diagnosis should be confirmed by needle biopsy. In hemangiomas, physicians are generally concerned to perform a biopsy because of the risk of bleeding. However, since the blood vessels that make up the hemangioma are veins, the risk of major bleeding is low if appropriate techniques are used. In biopsies performed with trucut (core) biopsy method, typical blood vessels and normal endothelial cells can be seen on pathology and diagnosis of hemangioma can be readily made.
If the hemangioma is small and does not cause complaints, regular follow-up is sufficient. However, large hemangiomas, especially if adjacent to the capsule of the liver, have a higher risk of bleeding and usually require treatment. Similarly, treatment is preferred if hemangiomas causing symptoms like pain.
The preferred treatment modalities in liver hemangiomas are chemoembolization and percutaneous ablation. In some patients, both methods should be applied. After treatment, even in large hemangiomas with diameters exceeding 20 cm, a marked reduction in size is generally seen.
The spine is a region where hemangiomas are frequently located. Spinal hemangiomas may involve one or more vertebrae. They grow slowly and weaken the bone structure of the spine. As a result, the vertebra can develop compression, fracture and pain. Rarely, they can grow towards the back of the vertebrae and compress the spinal cord and cause problems leading to paralysis.
Spinal hemangiomas are treated if they cause problems such as collapse and pain, or if there is significant weakening of the bone. In some cases embolization can be performed via the feeding arteries. In some cases, a needle can be placed from the skin directly into the hemangioma under CT guidance, and either a drug is injected that destroy the hemangioma (sclerotherapy) or a special cement is injected into the hemangioma to strengthen the vertebra and prevent collapse.
Limb (extremity) hemangiomas:
Arms and legs (extremities) and face are also frequently involved by the hemangiomas. Hemangiomas in these areas may be subcutaneous or intramuscular, and may be single or multiple. In some cases they can wrap important structures such as veins, nerves and tendons. Such hemangiomas should be distinguished from similar-looking masses called arteriovenous malformations (AVM) by color Doppler ultrasonography. AVMs are artery-rich in vasculature and high-flow is detected on color Doppler. In the treatment, embolization with angiography is performed and in some cases additional surgery is required. In hemangiomas, there is slow flow (low-flow) on Doppler ultrasound, and there is no place for embolization in treatment. The subcutaneous hemangiomas can easily be treated by both surgical and interventional methods. Hemangiomas located within the muscles are difficult to remove completely by surgery. Therefore, interventional therapies are preferred in the forefront. Sclerotherapy is the most common treatment modality. In sclerotherapy, thin needles are inserted into the hemangioma under ultrasound guidance and sclerosing substances are injected which destroy the veins. In order to obtain a good result, sclerotherapy should be performed at least several times at regular intervals.
Percutaneous ablation can be performed in hemangiomas not sufficiently shrunk by sclerotherapy. The most frequently applied technique for this purpose is laser ablation. In this process, a laser fiber is placed into the hemangioma and the tissue is destroyed with the heat produced by laser. This procedure should be performed with ultrasound guidance in experienced hands and structures such as nerves, vessels and tendons should be protected with special techniques.
Interventional oncology in cancer management
Prof Saim Yilmaz, MD