Infantile proliferative haemangioma

What is infantile proliferative haemangioma?

Infantile haemangioma (American spelling ‘hemangioma’) describes a benign (non-cancerous) condition affecting cutaneous blood vessels. It is known as a proliferative haemangioma because it is due to proliferating endothelial cells (the cells that line blood vessels).

Infantile proliferative hemangiomas usually develop shortly after birth. They are distinct from vascular malformations, which are usually present at birth and are less common.

Over 80% of infantile proliferative haemangiomas occur on the head and neck area. They grow to 80% of maximum size in the first three months and most stop growing at about 5 months. However, they may keep growing for up to 18 months.

After that, they undergo regression or involution. This can take as long as 3-10 years. Nearly all flat infantile proliferative haemangiomas eventually involute and disappear without treatment. However, regression of bulky haemangiomas tends to be incomplete, and they may leave an irregular atrophic scar or anetoderma (a dented scar) in at least 50% of cases.

Types of infantile proliferative haemangioma

Infantile proliferative haemangiomas are classified as superficial, deep or mixed lesions. They may be localised or segmental (involving a larger neuroectodermal unit).

• The superficial infantile haemangioma is also called capillary haemangioma, capillary naevus, strawberry haemangioma, strawberry naevus, and haemangioma simplex. The blood vessels in uppermost layers of the skin are dilated.
• Deep infantile haemangiomas are also called cavernous haemangiomas and are more deeply set in the dermis and subcutis. They appear as a bluish soft to firm swelling.
• Both types of haemangiomas may occur together in mixed angiomatous naevi when a strawberry naevus overlies a bluish swelling.

Segmental proliferative haemangiomas are more serious than localised haemangiomas.

• They occur at a younger age and grow up to ten times larger
• They are consequently more unsightly
• Other congenital anomalies may be associated with facial segmental haemangiomas (PHACE syndrome). These include posterior fossa abnormalities, haemangiomas, arterial abnormalities, cardiac abnormalities, and eye abnormalities.
• Likewise, segmental infantile haemangiomas involving the perineum may be associated with pelvic congenital anomalies, the PELVIS syndrome (perineal hemangioma with any of the following: external genital malformations, lipomyelomeningocele, vesicorenal abnormalities, imperforate anus, or skin tag)

Other haemangiomas

The haemangiomas described below are all very rare conditions.

The Kasabach-Merritt syndrome is also known as haemangioma-thrombocytopenia syndrome. It is a rare complication of a rapidly growing vascular lesion but is no longer thought to arise from an ordinary infantile proliferative haemangioma.

Which babies get proliferative haemangiomas?

Ten per cent of babies develop one or more haemangiomas. Localised haemangiomas are more common if the baby has a low birth weight, for example in the following circumstances.

• Females
• White skin
• Premature
• Multiple births (twins)
• Advanced maternal age
• Family history of infantile proliferative haemangioma

Hypoxia (inadequate oxygen to the skin) is now considered the likely reason for the proliferation of blood vessels. Endothelial progenitor cells (EPCs) circulate in a fetus and cause new blood vessels to form in response to hypoxia. Normally, EPCs have gone by the time a baby is born, but they may still be present in low birthweight or premature babies. As the EPCs disappear later in life, the haemangioma may regress.

Segmental haemangiomas are thought to arise early in gestation (6-8 weeks) as a developmental error.

Investigations in babies with infantile proliferative haemangioma

Infantile haemangiomas are usually diagnosed clinically and no investigations are necessary for the majority of superficial lesions.

Deep infantile haemangiomas or segmental haemangiomas are routinely investigated with ultrasound scanning. An ultrasound scan is also often performed when there is uncertainty about the diagnosis or whether underlying tissues are affected. Characteristically, a haemangioma has a firm lobular structure with vessels separating the lobules.

It may also be necessary to perform Magnetic Resonance Imaging (MRI) or angiography to help plan treatment. Children with complex lesions are best assessed by a panel of experts, including paediatrician, dermatologist, radiologist, ophthalmologist, vascular and plastic surgeons.

Haemangiomas arising over the lower part of the spine are sometimes a marker for occult spinal dysraphism (spina bifida), when spinal imaging may be appropriate.

When is treatment necessary for infantile proliferative haemangioma?

Because infantile haemangiomas are likely to improve or regress completely with time, there is no need for specific treatment in most cases. Treatment should be considered in the following circumstances.

• Very large and unsightly lesions
• Ulcerating haemangiomas (up to 5–25% of lesions)
• Lesions that impair vision, hearing, breathing or feeding
• If they fail to resolve by school age
• Haemangiomas that have a steep or stepped border, thick pebbled surface or combined superficial and deep components

The baby is best assessed early during the rapidly growing phase under the age of 3 to 5 months of age. If the lesion obstructs vision, it may prevent the development of normal sight.

What is the treatment for infantile proliferative haemangioma?

Propranolol is the treatment of choice for troublesome haemangiomas. Topical beta-blockers such as timolol, available as eye drops or 0.5% gel-forming solution, can be used off-label for small superficial haemangiomas.

Other possible treatments include:

• External compression therapy (bandaging)
• Ultrapotent topical steroids
• Topical antiseptics. Eosin, which also has antiangiogenic properties, has been reported to be of benefit.
• Oral corticosteroids in high dose, during the proliferative stage of segmental disease (mostly superceded by propranolol)
• Sometimes, intralesional steroid injections have been used for small haemangiomas.
• Vascular laser therapy at age 3 to 4 years, when lesions are stable
• Interferon-alpha may be useful but is rarely recommended, as it has been associated with the development of cerebral palsy in a few infants.
• Vincristine was reported effective in the past but is rarely used today
• Imiquimod has been reported to speed resolution in some cases.