Hemangiomas

Hemangiomas are benign vascular tumors resulting from abnormal proliferation of blood vessels. They occur in both children and adults, but the term is most commonly used for infantile and other pediatric vascular lesions. Hemangiomas can be located in the skin and subcutaneous tissues or occur internally, including the liver, bone, or other organs, though visceral involvement is less common.

Infantile hemangiomas are the most frequent vascular tumors in infancy. They typically appear a few weeks after birth, grow rapidly during the first several months (the proliferative phase), and then gradually slow their growth and begin a prolonged involution over years. By childhood many have regressed significantly, although some leave residual skin changes such as scarring or telangiectasia. Congenital hemangiomas are present at birth and are classified as rapidly involuting (RICH) or non-involuting (NICH) based on their course. Capillary and cavernous hemangiomas describe the predominant microscopic patterns, with capillary lesions usually more superficial and cavernous lesions deeper or larger.

Diagnosis is usually clinical, supported by imaging when deeper or visceral involvement is suspected. Ultrasound with Doppler or MRI may be used to assess extent and involvement of underlying structures. Biopsy is rarely needed due to bleeding risk.

Management depends on size, location, and symptoms. Many infantile hemangiomas require no treatment. Obvious or problematic lesions may be treated with propranolol as a first-line systemic therapy; topical timolol can be used for superficial lesions. Other options include corticosteroids, laser therapy, or surgical removal for residual deformity or complications. Complications can include ulceration, bleeding, functional impairment, or, in very large lesions, high-output heart failure. A life-threatening coagulopathy known as Kasabach–Merritt phenomenon is rare and more typical of certain other vascular tumors, not standard infantile hemangiomas. Overall prognosis is favorable, with most lesions eventually regressing or becoming less conspicuous.