What is a hemangioma?
A hemangioma is a benign tumor of endothelial cells, which normally coat blood vessels. The lesion is characterized by a dense collection of capillaries, which forms a superficial or deep nodule. Hemangiomas can arise in any part of the body, including the layers of the skin and internal organs.
Causes
The cause is currently unknown, however several studies have suggested the intervention of estrogen in the proliferation of hemangioma. In particular, hypoxia (oxygen deficiency) localized to soft tissues, associated with increased levels of circulating hormones after birth, can be a stimulus for the onset of the benign tumor. Some scientific evidence suggests, instead, a role of placental tissue during gestation. Other theories have been proposed, but further research is needed to confirm the causes of hemangioma development.
In hemangiomas, endothelial cells multiply at a very rapid rate. Under the microscope, the lesions consist of aggregates of thin blood vessels, endothelial lining and separated by poor connective tissue. Glut1 is a highly specific histochemical marker for hemangioma and can be used to differentiate it from vascular malformations.
Emagioma vs. vascular malformation
The terminology used to describe and classify vascular abnormalities and blood vessel nodules has changed over time. The term "hemangioma" was originally used to describe any vascular lesion similar to a tumor, congenital or late-onset. In reality, it is possible to distinguish these conditions in two families: 1) self-involutive tumors and 2) malformations present at birth and substantially stable. This distinction makes early differentiation possible, between lesions that tend to resolve spontaneously (hemangioma) and permanent ones (vascular malformations).
Emagioma | Vascular malformation | |
Histology | Elevated proliferation of endothelial cells. | Normal cell turnover. |
Presence at birth | Usually, absent. | Present (not always obvious). |
clinic | Clear after a few weeks after birth. The proliferative phase continues for 1-2 years, then the hemangioma spontaneously involves. | It grows proportionally with the development of the child. |
Diagnosis | History and clinical signs. | Imaging (MRI, CT and angiography). |
Treatment | Observation; if the hemangioma is large, in anatomically sensitive areas and if the involution is not complete, it can be treated with corticosteroids or surgically. | Depends on location, size, symptoms, etc. Treatment options include sclerotherapy with or without excision and surgery. |
Course
How a hemangioma develops
Hemangiomas go through three stages of development and involution.
- In the proliferation phase, a hemangioma grows very rapidly, increasing its size. The lesion becomes more evident assuming a bright red color and an irregular appearance. However, if the hemangioma is deep, the skin may appear bluish and only slightly raised. The proliferation phase can last up to twelve months.
- In the resting phase, few changes occur in the appearance of a hemangioma. This period usually lasts up to 1-2 years of age.
- In the involution phase, a hemangioma begins to gradually reduce its size. During this period, the hemangioma will be soft to the touch, while the color will tend to fade (it becomes opaque purple or gray). Sometimes the overlying skin may appear slightly wrinkled.
There is no reliable way to predict the speed at which a particular hemangioma will be reduced. In general, 50% of injuries disappear from the age of 5-7 years and most cases resolve completely within 10 years. Some congenital forms (present at birth) tend to reduce more rapidly, while others may not regress (non-involutive congenital hemangiomas).
Symptoms
Hemangiomas usually do not cause symptoms during or after their formation. However, they can cause the appearance of some signs if they reach large dimensions or grow in an anatomically sensitive area. Most children develop a single lesion on the body, but occasionally, hemangiomas can appear in multiple positions.
Capillary and cavernous hemangioma
- Capillary hemangioma occurs in the superficial layers of the skin.
- A cavernous hemangioma can grow in the deeper skin layers or in organs such as eyes, kidneys, lungs, colon and brain. Hemangiomas within the body usually go unnoticed until they grow and reach large dimensions or form multiple lesions. Depending on the size and their location, hemangiomas can interfere with breathing, feeding, urination or normal vision development.
Cutaneous hemangioma
The lesion may form on the surface of the skin or in the subcutaneous fat layer (hypodermis).
In the beginning, a superficial hemangioma can appear as a small area of light skin, on which a red-burgundy stain develops, raised above the skin plane. This type of hemangioma is found mainly on the neck or face (lip, nose, etc.). Deep hemangiomas may not be evident until 3-4 months of life, but the growth of the lesion may be suspected due to a slight discoloration of the skin that is barely visible at birth or due to the appearance of a lump. Later, deep hemangiomas can take on a bluish color.
Hepatic hemangioma
Hemangiomas can develop inside or on the surface of the liver. Rarely, these injuries cause symptoms. They are usually discovered when investigations are performed to investigate an unrelated condition. Hepatic hemangiomas are considered to be estrogen-sensitive.
Complications
Possible complications of a hemangioma include:
- Bleeding : it is the most common complication of hemangiomas and occurs because the skin overlying the hemangioma is much thinner than normal. If the skin is scratched, the area may bleed. Bleeding can be stopped effectively, with direct and continuous hand pressure.
- Ulcerated hemangiomas : in some cases, an ulcer may develop on the surface of the lesion. This can lead to pain, bleeding, scars or secondary infections. Ulceration in deeper areas can be problematic. Hemangiomas around the mouth or in the natural folds of the skin, such as the axilla, the ear and the neck, are more likely to become ulcerated, often due to the friction between the surfaces. Ulcers are usually managed with antibiotics, topical medications and special medications, to be used under medical supervision.
- Hemangiomas affecting the eye : capillary hemangiomas involving the eyelids, the surface of the eye (conjunctiva) or the eye socket (orbit) can cause long-term effects on the vision of a child. The lesion can press on the eyeball, deforming it slightly and influencing the way the images are focused on the retina, which in turn alters the messages sent to the brain by the eye. This can interfere with normal vision development and cause amblyopia. If the hemangioma involves the eye socket, the lesion can lead to increased intraocular pressure and cause glaucoma. In orbit, hemangiomas can also press on the optic nerve, causing atrophy and loss of vision.
- Hemangiomas that obstruct the airways : sometimes, a hemangioma that develops on the jaw, chin or neck can affect the airways. The first sign of this complication is a shrill sound emitted by the patient with each breath. If the hemangioma grows further, it can cause breathing difficulties and obstruct the airways.
Diagnosis
Most superficial lesions are clearly evident and can be recognized easily during a physical examination. The presence of a deep hemangioma is confirmed by imaging studies (typically MRI, ultrasound or CT). These diagnostic tests assess the position and extent of the benign tumor, check the depth of the affected blood vessels and rule out associated anomalies. If the diagnosis is not clear and cannot be defined based on the clinical presentation and / or imaging findings, a biopsy can be used to rule out any malignant neoplasms. Other investigations may be necessary to verify the presence of medical conditions associated with hemangioma.
Treatments
Most hemangiomas disappear without treatment, leaving minimal signs. However, the involution process can take several years and the patient may experience discomfort due to the psychosocial implications associated with visible skin changes. For this reason, if an adequate spontaneous improvement has not occurred in the child, it is important to consider the treatment before school age. The small lesions in relief, sometimes, are treated with corticosteroids, injected directly into the hemangioma, to reduce its growth and stop the inflammation. Steroids can also be administered orally or applied on the surface of the tumor. Laser treatment can be useful in case of very early and flat superficial hemangiomas, if they appear in aesthetically significant areas, or for those lesions that leave residual superficial blood vessels, in the case of incomplete resolution. In some cases, a pulse laser can be used to reduce redness and to accelerate hemangioma healing. A medicated becaplermin gel (Regranex) is often used to treat ulcerations of skin lesions. Recently, a clinical trial showed high success rates in the treatment of hemangioma with propranolol, a beta-blocker drug used to control blood pressure. This can be taken orally or applied locally if the lesion is very small and not raised. Therapy is also effective in reducing severe haemangiomas in children, especially if started within the first 6 months after onset. Propranolol has fewer side effects than corticosteroid drugs, but it can affect heart rate and blood pressure, so it requires careful monitoring. Currently, a topical therapy that involves the application of a gel containing beta-blockers and timolol, for small facial hemangiomas that do not justify taking a systemic drug, is also being tested. Other treatments include the use of interferon or vincristine and can be considered if the first-line therapy is not effective. Large haemangiomas, when wrapped, can leave visible skin changes, secondary to a severe stretching of the surrounding skin. These residual changes can be improved with plastic surgery . Sometimes, surgical removal is indicated in the event of inadequacy or delay in starting treatment.
Hemangiomas within the body, on the other hand, may require surgery if they are exceptionally large, cause pain, interfere with the normal functioning of the organ or if other medical therapies are not effective.
Treatment options include:
- Surgical removal of hemangioma;
- Surgical removal of the damaged organ or the injured area;
- Ligation of the main artery, which supplies blood to hemangioma.
The airway obstruction often requires the execution of a tracheostomy (or tracheotomy), which involves creating an artificial opening in the trachea, to improve breathing. When hemangiomas interfere with vision, breathing or hearing, or when they threaten significant cosmetic damage (facial injuries, in particular, of the nose and lips), they should be treated as soon as possible.
