Lymphangiomas are rare, accounting for 4% of all vascular tumors in children. Although lymphangioma can become evident at any age, 50% are seen at birth, and 90% of lymphangiomas are evident by 2 years of age.

The direct cause of lymphangioma is a blockage of the lymphatic system as a fetus develops, although symptoms may not become visible until after the baby is born. The cause remains unknown. Why the embryonic lymph sacs remain disconnected from the rest of the lymphatic system is also not known.

Cystic lymphangioma that emerges during the first two trimesters of pregnancy is associated with genetic disorders such as Noonan syndrome and trisomies 13, 18, and 21. Chromosomal aneuploidy such as Turner syndrome or Down syndrome were found in 40% of patients with cystic hygroma.

Oral propranolol appears to be the most effective treatment for reducing the size of capillary hemangiomas in children and is more effective than placebo, observation without intervention, or oral corticosteroids.

Superficial lymphatic malformation (also known as "Lymphangioma circumscriptum") is a congenital malformation of the superficial lymphatics, presenting as groups of deep-seated, vesicle-like papules resembling frog spawn, at birth or shortly thereafter.

A capillary hemangioma (also known as an Infantile hemangioma, Strawberry hemangioma, and Strawberry nevus) is the most common variant of hemangioma which appears as a raised, red, lumpy area of flesh anywhere on the body, though 83% occur on the head or neck area. These marks occur in about 10% of all births, and usually appear between one and four weeks after birth. It may grow rapidly, before stopping and slowly fading. Some are gone by the age of 2, about 60% by 5 years, and 90–95% by 9 years. Capillary hemangioma is a vascular anomaly.

Capillary hemangiomas occur 5 times more often in female infants than in males, and mostly in Caucasian populations. Additionally, low birthweight infants have a 26% chance of developing a hemangioma.

It is the most common tumor of orbit and periorbital areas in childhood. It may occur in the skin, subcutaneous tissues and mucous membranes of oral cavities and lips as well as in the liver, spleen and kidneys. While this birthmark may be alarming in appearance, physicians generally counsel that it be left to disappear on its own, unless it is in the way of vision or blocking the nostrils.

Kaposiform hemangioendothelioma (KHE) is a rare vascular neoplasm that is locally aggressive but without metastatic potential. It occurs particularly in the skin, deep soft tissue, retroperitoneum, mediastinum, and rarely in bone. Although lesions occur solitary, they often involve large areas of the body, such as the head/neck region (40%), trunk (30%), or extremity (30%).

Usually, it is present at birth as a flat, reddish-purple, tense and edematous lesion.

Although half of lesions are congenital, 58% of KHE develop during infancy, 32% between age 1 and 10 years (32%) and 10% after 11 years of age. Moreover, adult onset has been described too with mainly males being affected. Both sexes are affected equally in children.

Lesions are often greater than 5 cm in diameter and can cause visible deformity and pain. During early childhood, KHE may enlarge and after 2 years of age, it may partially regress. Though, it usually persists longterm. In addition, 50% of patients suffer from coagulopathy due to thrombocytopenia (<25,000/mm3), presenting with petechiae and bleeding. This is called the Kasabach-Merritt Phenomenon, which is caused by trapping of platelets and other clotting factors within the tumor. Kasabach-Merritt Phenomenon is less likely in patients with lesions less than 8 cm. As two-thirds of adult-onset KHE tumors are less than 2 cm, KHE in adults is rarely associated with Kasabach-Merritt Phenomenon.

Patients with KHE and Kasabach-Merritt Phenomenon present with petechiae and ecchymosis.

Most KHE tumors are diffuse involving multiple tissue planes and important structures. Resection of KHE is thus often difficult. Treatment of kaposiform hemangioendothelioma is therefore medical. The primary drug is interferon alfa, which is successful in 50% of children. Another option is vincristine, which has lots of side-effects, but has a response rate of 90%. Drug therapy is often used in shrinking the tumor and treating the coagulopathy. However, many of these kaposiform hemangioendotheliomas do not completely regress and remain as a much smaller asymptomatic tumor. However, KHE still has a high mortality rate of 30%. Although complete surgical removal with a large margin has the best reported outcome, it is usually not done because of the risk of bleeding, extensiveness, and the anatomic site of the lesion.

Operative management may be possible for small or localized lesions. Removal of larger areas also may be indicated for symptomatic patients or for patients who have failed farmacotherapy. Resection is not required for lesions that are not causing functional problems, because KHE is benign and because resection could cause deformity.

A cystic hygroma, also known as cystic lymphangioma and macrocystic lymphatic malformation, is an often congenital multiloculated lymphatic lesion that can arise anywhere, but is classically found in the left posterior triangle of the neck and armpits. This is the most common form of lymphangioma. It contains large cyst-like cavities containing lymph, a watery fluid that circulates throughout the lymphatic system. Microscopically, cystic hygroma consists of multiple locules filled with lymph. In the depth, the locules are quite big but they decrease in size towards the surface.

Cystic hygromas are benign, but can be disfiguring. It is a condition which usually affects children; very rarely it can present in adulthood.

Cystic hygroma is also known as lymphatic malformation. Currently, the medical field prefers to use the term lymphatic malformation because the term cystic hygroma means water tumor. Lymphatic malformation is more commonly used now because it is a sponge-like collection of abnormal growth that contains clear lymphatic fluid. The fluid collects within the cysts or channels, usually in the soft tissue. Cystic hygromas occur when the lymphatic vessels that make up the lymphatic system are not formed properly. There are two types of lymphatic malformations. They are macrocystic lymphatic malformations, large cysts, and microcystic, small cysts. A person may have only one kind of the malformation or can have a mixture of both macro and micro cysts.

Cystic hygroma can be associated with a nuchal lymphangioma or a fetal hydrops. Additionally, it can be associated with Turner syndrome or with Noonan syndrome.

A lethal version of this condition is known as Cowchock Wapner Kurtz syndrome that, in addition to cystic hygroma, includes cleft palate and lymphedema, a condition of localized edema and tissue swelling caused by a compromised lymphatic system.

Congenital hemangioma can be distinguished from infantile hemangioma because it is fully developed at birth. It forms during prenatal life and has reached its maximal size at birth. Congenital hemangioma can even be diagnosed in utero by prenatal ultrasound. Unlike IH, CH is more common in the extremities, has an equal sex distribution, and is solitary, with an average diameter of 5 cm. It commonly presents in the head and neck and in the lower extremities.

Congenital hemangioma are divided into 2 subgroups: the rapidly involuting congenital hemangiomas (RICHs) and the non-involuting congenital hemangiomas(NICHs).

The rapidly involuting congenital hemangioma, RICH, presents at birth as a solitary raised tumor with a central depression, scar, or ulceration surrounded by a rim of pallor. It is noted for its involution, which typically begins several weeks after birth and is completed no later than 14 months of age. After regression RICH may cause a residual deformity, such as atrophic skin and subcutaneous tissue. It mainly affects the limbs (52%), but also the head and neck region (42%) and the trunk (6%).

The non-involuting congenital hemangioma, NICH, presents as a solitary, well-circumscribed reddish-pink to purple plaque with central telangiectasia and hypopigmented rim. In contrast to RICH, NICH does not involute and rarely ulcerates. It persists into late childhood and can even mimic a vascular malformation by growing commensurately with the child. Although NICH can resemble RICH in its external appearance, it can be differentiated from RICH by a greater elevation and coarse telangiectases. It mainly affects the head and neck region (43%), but also the limbs (38%) and the trunk (19%).

Surgical resection for congenital hemangiomas is rarely needed, because RICH undergoes postnatal regression and NICH is benign and often asymptomatic. Resection may be indicated to improve the appearance of the affected area, as long as the surgical scar is less noticeable than the lesion. Other indications are problematic ulcers with persistent bleeding or chronic infection.

Although most NICH lesions are non-problematic and do not cause significant deformity, the threshold for resection of NICH is lower, because it neither involutes, nor responds to pharmacotherapy. RICH tumors are observed until involution is completed. Involuted RICH may leave behind atrophic tissue, which can be reconstructed with autologous grafts. It is often best to postpone excision until regression is complete.

There are effective pharmacologic treatments, which include intralesional corticosteroid injection, systemic corticosteroid injection, interferon α-2a or α-2b and angiogenic inhibitors. The use of corticosteroids leads to accelerated regression in 30%, stabilization of growth in 40%, lightening of color and softening of the tumor. However, 30% shows minimal or no response. Another drug treatment is interferon α-2a or α-2b. It is often used for patients who did not respond to corticosteroids. Although the response rate is much slower, it has been successful for 80% of children treated. The most serious side effect of interferon is a spastic diplegia. Other therapeutic options are embolization and pulsed-dye laser, which improves residual telangiectasias in RICH and in NICH.

A baby with a prenatally diagnosed cystic hygroma should be delivered in a major medical center equipped to deal with neonatal complications, such as a neonatal intensive care unit. An obstetrician usually decides the method of delivery. If the cystic hygroma is large, a cesarean section may be performed. After birth, infants with a persistent cystic hygroma must be monitored for airway obstruction. A thin needle may be used to reduce the volume of the cystic hygroma to prevent facial deformities and airway obstruction. Close observation of the baby by a neonatologist after birth is recommended. If resolution of the cystic hygroma does not occur before birth, a pediatric surgeon should be consulted.

Cystic hygromas that develop in the third trimester, after thirty weeks gestation, or in the postnatal period are usually not associated with chromosome abnormalities. There is a chance of recurrence after surgical removal of the cystic hygroma. The chance of recurrence depends on the extent of the cystic hygroma and whether its wall was able to be completely removed.

Treatments for removal of cystic hygroma are surgery or sclerosing agents which include:

- Bleomycin

- Doxycycline

- Ethanol (pure)

- Picibanil (OK-432)

- Sodium tetradecyl sulfate

Acquired progressive lymphangioma (also known as "Benign lymphangioendothelioma") is a group of lymphangiomas that occur anywhere in young individuals, grow slowly, and present as bruise-like lesions or erythematous macules.

A tufted angioma (also known as an "Acquired tufted angioma," "Angioblastoma," "Angioblastoma of Nakagawa," "Hypertrophic hemangioma," "Progressive capillary hemangioma," and "Tufted hemangioma") usually develops in infancy or early childhood on the neck and upper trunk, and is an ill-defined, dull red macule with a mottled appearance, varying from 2 to 5 cm in diameter.

Hyperkeratotic cutaneous capillary-venous malformation is a cutaneous condition characterized also by inherited cerebral capillary malformations.

Pyogenic granuloma (also known as a "eruptive hemangioma", "granulation tissue-type hemangioma", "granuloma gravidarum", "lobular capillary hemangioma", "pregnancy tumor", and "tumor of pregnancy") is a vascular lesion that occurs on both mucosa and skin, and appears as an overgrowth of tissue due to irritation, physical trauma, or hormonal factors. It is often found to involve the gums, the skin and nasal septum, and has also been found far from the head such as in the thigh.

Most stork bites on the face go away completely in about 18 months. Stork bites on the back of the neck usually do not go away.

Phakomatosis pigmentovascularis is a rare neurocutanous condition where there is coexistence of a capillary malformation (port-wine stain) with various melanocytic lesions, including dermal melanocytosis (Mongolian spots), nevus spilus, and nevus of Ota.

Capillary aneurysms are flesh colored solitary lesions, resembling an intradermal nevus, which may suddenly grow larger and darker and become blue-black or black as a result of thrombosis.

The appearance of pyogenic granuloma is usually a color ranging from red/pink to purple, and can be smooth or lobulated. Younger lesions are more likely to be red because of the high number of blood vessels. Older lesions begin to change into a pink color. Size commonly ranges from a few millimeters to centimeters, though smaller or larger lesions may occur. A pyogenic granuloma can be painful, especially if located in an area of the body where it is constantly disturbed. Pyogenic granulomas can grow rapidly and will often bleed profusely with little or no trauma. They may exude an oil like substance, causing the surface to be damp. This is especially true if the granuloma is located on the scalp.

Pyogenic granulomas may be seen at any age, and are more common in females than males. In pregnant women, lesions may occur in the first trimester with an increasing incidence up until the seventh month, and are often seen on the gums. Epulis granulomatosum is a variant of pyogenic granuloma that forms only on gingiva, and is often seen forming in a recent extraction socket. Pyogenic granulomas appear on the gingiva in 75% of cases, more often in the maxillary than mandibular jaw. Anterior areas are more often affected than posterior areas. It can also be found on the lips, tongue, and inner cheek. Poor oral hygiene or trauma are usually precipitating factors.

One study has suggested a correlation between pyogenic granulomas and Bartonella seropositivity. However, this association has been questioned by others. The microscopic appearance of a pyogenic granuloma consists of highly vascular granulation tissue. Inflammation is present. The lesion may have a fibrous character if it is older, and the surface may have ulcerations. Pyogenic granulomas rarely occur in the conjunctiva, cornea or connective tissue of the eye following minor local trauma. Grossly these mass lesions resemble those occurring at more common sites. The relationship of these lesion to lobular capillary hemangiomas of skin and oropharyngeal mucosa commonly referred to as pyogenic granuloma is uncertain.

The birth defect affects men and women equally, and is not limited to any racial group. It is not certain if it is genetic in nature, although testing is ongoing. There is some evidence that it may be associated with a translocation at t(8;14)(q22.3;q13). Some researchers have suggested AGGF1 has an association.

Phakomatosis pigmentovascularis is subdivided into five types:

- Type 1 PWS + epidermal nevus

- Type 2 (most common): PWS + dermal melanocytosis +/- nevus anemicus

- Type 3: PWS + nevus spilus +/- nevus anemicus

- Type 4: PWS + nevus spilus + dermal melanocytosis +/- nevus anemicus

- Type 5: CMTC (Cutis marmorata telangiectatica congenita) + dermal melanocytosis

They all can contain capillary malformation. Type 2 is the most common and can be associated with granular cell tumor. Some further subdivide each type into categories A & B; with A representing oculocutaneous involvement and subtype B representing extra oculocutaneous involvement. Others have proposed fewer subtypes but currently this rare entity is mostly taught as having five subtypes currently.

Baylor College of Medicine in Houston, Texas has conducted ACD research since 2001.

Stork bites occur in a significant number of newborns, with estimates ranging from to ; they are reported more frequently for white babies than for infants of other races. They result from a dilation of capillaries in the skin, and may become darker when the child cries or strains.

The birthmarks, which are pinkish and irregularly shaped, occur most frequently on the nape of the neck; however, they are also common on the forehead, eyelids and upper lip. A baby may be born with a stork bite, or the birthmark may appear in the first months of life. They may also be found occasionally on other parts of the body. The skin is not thickened and feels no different from anywhere else on the body; the only difference is in appearance.

Although there is no definitive reporting on its incidence, acrocyanosis shows prevalence in children and young adults than in patients thirty years of age or older. Epidemiological data suggests that cold climate, outdoor occupation, and low body mass index are significant risk factors for developing acrocyanosis. As expected, acrocyanosis would be more prevalent in women than in men due to differences in BMI. However, the incidence rate of acrocyanosis often decreases with increasing age, regardless of regional climate. It completely resolves in many women after menopause implying significant hormonal influences.

Lymphangiomatosis (LYMF) is a condition where a lymphangioma is not present in a single localised mass, but in a widespread or multifocal manner. It is a rare type of tumor which results from an abnormal development of the lymphatic system.

It is thought to be the result of congenital errors of lymphatic development occurring prior to the 20th week of gestation. Lymphangiomatosis is a condition marked by the presence of cysts that result from an increase both in the size and number of thin-walled lymphatic channels that are abnormally interconnected and dilated. 75% of cases involve multiple organs. It typically presents by age 20 and, although it is technically benign, these deranged lymphatics tend to invade surrounding tissues and cause problems due to invasion and/or compression of adjacent structures. The condition is most common in the bones and lungs and shares some characteristics with Gorham’s disease. Up to 75% of patients with lymphangiomatosis have bone involvement, leading some to conclude that lymphangiomatosis and Gorham’s disease should be considered as a spectrum of disease rather than separate diseases. When it occurs in the lungs, lymphangiomatosis has serious consequences and is most aggressive in the youngest children. When the condition extends into the chest it commonly results in the accumulation of chyle in the linings of the heart and/or lungs.

Chyle is composed of lymph fluid and fats that are absorbed from the small intestine by specialized lymphatic vessels called lacteals during digestion. The accumulations are described based on location: chylothorax is chyle in the chest; chylopericardium is chyle trapped inside the sack surrounding the heart; chyloascites is chyle trapped in the linings of the abdomen and abdominal organs. The presence of chyle in these places accounts for many of the symptoms and complications associated with both lymphangiomatosis and Gorham’s disease. The incidence of lymphangiomatosis is unknown and it is often misdiagnosed. It is separate and distinct from lymphangiectasis, lymphangioleiomyomatosis (LAM), pulmonary capillary hemangiomatosis, Kaposi’s sarcoma, and kaposiform hemangioendothelioma. Its unusual nature makes lymphangiomatosis (and Gorham’s disease) a diagnostic and therapeutic challenge. A multidisciplinary approach is generally necessary for optimal diagnosis and symptom management. The term literally means lymphatic system (lymph) vessel (angi) tumor or cyst (oma) condition (tosis).

Lymphangiomatosis can occur at any age, but the incidence is highest in children and teenagers. Signs and symptoms are typically present before the age of 20 and the condition is often under-recognized in adults.

It affects males and females of all races and exhibits no inheritance pattern. The medical literature contains case reports from every continent.

Because it is so rare, and commonly misdiagnosed, it is not known exactly how many people are affected by this disease.

Two broad types of genetic abnormality have been found to cause ACDMPV: (1) a mutation of the FOXF1 gene on chromosome 16, or (2) other genetic abnormalities such as deletions in areas of chromosome 16 that regulate the expression of the "FOXF1" gene. New genetic abnormalities are being found regularly, but at present around 80-90% of infants with confirmed ACDMPV can be found to have one of these abnormalities. The genetic abnormalities responsible for ACDMPV in the remaining 10-20% of cases are currently being investigated including testing for deletions farther away from the FOXF1 gene on chromosome 16 and whole exome testing.