Lymphangioma

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Lymphatic malformation or Lymphangioma
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Lymphatic malformation of the neck
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Lymphatic malformations (the term lymphangioma has fallen out of favor) are benign slow-flow type of vascular malformation of the lymphatic system characterized by lymphatic vessels which do not connect to the normal lymphatic circulation.

Contents

Lymphatic malformations can be macrocystic, microcystic, or a combination of the two. [1] Macrocystic have cysts greater than 2 cubic centimetres (0.12 cu in), and microcystic lymphatic malformation have cysts that are smaller than 2 cubic centimetres (0.12 cu in). [2]

These malformations can occur at any age and may involve any part of the body, but 90% occur in children less than 2 years of age and involve the head and neck. These malformations are either congenital or acquired. Congenital lymphangiomas are often associated with chromosomal abnormalities such as Turner syndrome, although they can also exist in isolation. Lymphangiomas are commonly diagnosed before birth using fetal ultrasonography. Acquired lymphangiomas may result from trauma, inflammation, or lymphatic obstruction.

Most lymphangiomas are benign lesions that result only in a soft, slow-growing, "doughy" mass. Since they have no chance of becoming malignant, lymphangiomas are usually treated for cosmetic reasons only. Rarely, impingement upon critical organs may result in complications, such as respiratory distress when a lymphangioma compresses the airway. Treatment includes aspiration, surgical excision, laser and radiofrequency ablation, and sclerotherapy.

Terminology

The International Society for the Study of Vascular Anomalies (ISSVA) classification is a basic and systematic classification of vascular anomalies with international acceptance. [3]

As such terms such as "Lymphangioma" and "Cystic Hygroma", which were used widely in the past, are outdated. Newer research may only reference ISSVA terminology and, as a consequence, sources of information can be missed by doctors and patients unaware of the ISSVA convention.

Terminology
ISSVA nameOutdated names
Lymphatic malformationLymphangioma, Cystic hygroma, Lymphangioma circumscriptum, Cavernous lymphangioma, lymphangiomatosis
Venous malformationCaveronous Hemangioma

Notes

Signs and symptoms

There are three distinct types of lymphangioma, each with their own symptoms. They are distinguished by the depth and the size of abnormal lymph vessels, but all involve a malformation of the lymphic system. Lymphangioma circumscriptum can be found on the skin's surface, and the other two types of lymphangiomas occur deeper under the skin.[ citation needed ]

Causes

The direct cause of lymphatic malformation 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. [7]

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 [8] were found in 40% of patients with cystic hygroma. [9]

Pathophysiology

Proliferating lymphangioma, H&E stain. Sometimes endothelial cells begin to divide excessively. SkinTumors-PA100979.JPG
Proliferating lymphangioma, H&E stain. Sometimes endothelial cells begin to divide excessively.

In 1976, Whimster studied the pathogenesis of lymphangioma circumscriptum, finding lymphatic cisterns in the deep subcutaneous plane are separated from the normal network of lymph vessels. They communicate with the superficial lymph vesicles through vertical, dilated lymph channels. Whimster theorized the cisterns might come from a primitive lymph sac that failed to connect with the rest of the lymphatic system during embryonic development.[ citation needed ]

A thick coat of muscle fibers that cause rhythmic contractions line the sequestered primitive sacs. Rhythmic contractions increase the intramural pressure, causing dilated channels to come from the walls of the cisterns toward the skin. He suggested that the vesicles seen in lymphangioma circumscriptum are outpouchings of these dilated projecting vessels. Lymphatic and radiographic studies support Whimsters observations. Such studies reveal that big cisterns extend deeply into the skin and beyond the clinical lesions. Lymphangiomas that are deep in the dermis show no evidence of communication with the regular lymphatics. The cause for the failure of lymph sacs to connect with the lymphatic system is not known. [7]

Microscopically, the vesicles in lymphangioma circumscriptum are greatly dilated lymph channels that cause the papillary dermis to expand. They may be associated with acanthosis and hyperkeratosis. There are many channels in the upper dermis which often extend to the subcutis (the deeper layer of the dermis, containing mostly fat and connective tissue). The deeper vessels have large calibers with thick walls which contain smooth muscle. The lumen is filled with lymphatic fluid, but often contains red blood cells, lymphocytes, macrophages, and neutrophils. The channels are lined with flat endothelial cells. The interstitium has many lymphoid cells and shows evidence of fibroplasia (the formation of fibrous tissue). Nodules (A small mass of tissue or aggregation of cells) in cavernous lymphangioma are large, irregular channels in the reticular dermis and subcutaneous tissue that are lined by a single layer of endothelial cells. Also an incomplete layer of smooth muscle also lines the walls of these channels. The stroma consists of loose connective tissue with a lot of inflammatory cells. These tumors usually penetrate muscle. Cystic hygroma is indistinguishable from cavernous lymphangiomas on histology. [7]

The typical history of Lymphangioma circumscriptum shows a small number of vesicles on the skin at birth or shortly after. In subsequent years, they tend to increase in number, and the area of skin involved continues to expand. Vesicles or other skin abnormalities may not be noticed until several years after birth. Usually, lesions are asymptomatic or do not show any evidence of a disease, but, mostly, patients may have random break outs of some bleeding and major drainage of clear fluid from ruptured vesicles.[ citation needed ]

Cavernous lymphangioma first appears during infancy, when a rubbery nodule with no skin changes becomes obvious in the face, trunk, or extremity. These lesions often grow at a rapid pace, similar to that of raised hemangiomas. No family history of prior lymphangiomas is described.[ citation needed ]

Cystic hygroma causes deep subcutaneous cystic swelling, usually in the axilla, base of the neck, or groin, and is typically noticed soon after birth. If the lesions are drained, they will rapidly fill back up with fluid. The lesions will grow and increase to a larger size if they are not completely removed in surgery. [7]

Diagnosis

Cases of lymphangioma are diagnosed by histopathologic inspection. [10] In prenatal cases, lymphangioma is diagnosed during the late first trimester or early second trimester using an ultrasound. Other imaging methods such as CT and MRI scans are useful in treatment planning, delineate the size of the lesion, and determine its surrounding vital structures. T2-weight MRI is useful to differentiate lymphangioma from surrounding structures due to its high T2 signal. [11]

Classification

Cavernous lymphangioma, H&E stain. Irregular, dilated spaces are visible in dermis. SkinTumors-PB061069.JPG
Cavernous lymphangioma, H&E stain. Irregular, dilated spaces are visible in dermis.

Lymphangiomas have traditionally been classified into three subtypes: capillary and cavernous lymphangiomas and cystic hygroma. This classification is based on their microscopic characteristics. A fourth subtype, the hemangiolymphangioma is also recognized. [12]

Capillary lymphangiomas
Capillary lymphangiomas are composed of small, capillary-sized lymphatic vessels and are characteristically located in the epidermis.[ citation needed ]
Cavernous lymphangiomas
Composed of dilated lymphatic channels, cavernous lymphangiomas characteristically invade surrounding tissues.[ citation needed ]
Cystic hygromas
Cystic hygromas are large, macrocystic lymphangiomas filled with straw-colored, protein-rich fluid.[ citation needed ]
Hemangiolymphangioma
As suggested by their name, hemangiolymphangiomas are lymphangiomas with a vascular component.

Lymphangiomas may also be classified into microcystic, macrocystic, and mixed subtypes, according to the size of their cysts. [12]

Microcystic lymphangiomas
Microcystic lymphangiomas are composed of cysts, each of which measures less than 2 cm3 in volume.[ citation needed ]
Macrocystic lymphangiomas
Macrocystic lymphangiomas contain cysts measuring more than 2 cm3 in volume.
Mixed lymphangiomas
Lymphangiomas of the mixed type contain both microcystic and macrocystic components.

Finally, lymphangiomas may be described in stages, which vary by location and extent of disease. In particular, stage depends on whether lymphangiomas are present above or superior to the hyoid bone (suprahyoid), below or inferior to the hyoid bone (infrahyoid), and whether the lymphangiomas are on one side of the body (unilateral) or both (bilateral). [12]

Stage I
Unilateral infrahyoid.
Stage II
Unilateral suprahyoid.
Stage III
Unilateral suprahyoid and infrahyoid.
Stage IV
Bilateral suprahyoid.
Stage V
Bilateral suprahyoid and infrahyoid.

Treatment

Treatment for cystic hygroma involves the removal of the abnormal tissue; however, complete removal may be impossible without removing other normal areas. Surgical removal of the tumor is the typical treatment provided, with the understanding that additional removal procedures will most likely be required as the lymphangioma grows. Most patients need at least two procedures done for the removal process to be achieved. Recurrence is possible but unlikely for those lesions able to be removed completely via excisional surgery. [13] Radiotherapy and chemical cauteries are not as effective with the lymphangioma than they are with the hemangioma. [14] Draining lymphangiomas of fluid provides only temporary relief, so they are removed surgically. Cystic Hygroma can be treated with OK432 (Picibanil).

Lymphangioma circumscription can be healed when treated with a flashlamp pulsed dye laser, although this can cause port-wine stains and other vascular lesions. [15]

Orbital lymphangiomas, which carry significant risks from surgical removal, can also be treated with sclerosing agents, systemic medication, or through observation. [16]

Sclerotherapy

The least invasive and most effective form of treatment is now performed by interventional radiologists. A sclerosing agent, such as 1% or 3% sodium tetradecyl sulfate, bleomycin, doxycycline, or ethanol, may be directly injected into a lymphocele. "All sclerosing agents are thought to work by ablating the endothelial cells of the disrupted lymphatics feeding into the lymphocele." [17]

Sirolimus

Sirolimus is used to treat lymphangioma. Treatment with sirolimus can decrease pain and the fullness of venous malformations, improve coagulation levels, and slow the growth of abnormal lymphatic vessels. [18] Sirolimus is a relatively new medical therapy for the treatment of vascular malformations, [19] in recent years, sirolimus has emerged as a new medical treatment option for both vascular tumors and vascular malformations, as a mammalian target of rapamycin (mTOR), capable of integrating signals from the PI3K/AKT pathway to coordinate proper cell growth and proliferation. [20] Sirolimus (rapamycin, trade name Rapamune) is a macrolide compound. It has immunosuppressant and antiproliferative functions in humans. It inhibits activation of T cells and B cells by reducing their sensitivity to interleukin-2 (IL-2) through mTOR inhibition. [21]

Prognosis

The prognosis for lymphangioma circumscriptum and cavernous lymphangioma is generally excellent. This condition is associated with minor bleeding, recurrent cellulitis, and lymph fluid leakage. Two cases of lymphangiosarcoma arising from lymphangioma circumscriptum have been reported; however, in both of the patients, the preexisting lesion was exposed to extensive radiation therapy.[ citation needed ]

In cystic hygroma, large cysts can cause dysphagia, respiratory problems, and serious infection if they involve the neck. Patients with cystic hygroma should receive cytogenetic analysis to determine if they have chromosomal abnormalities, and parents should receive genetic counseling because this condition can recur in subsequent pregnancies. [7]

Complications after surgical removal of cystic hygroma include damage to the structures in the neck, infection, and return of the cystic hygroma. [13]

Epidemiology

Lymphatic malformations are rare, accounting for 4% of all vascular tumors in children. [7] Although lymphangioma can become evident at any age, 50% are seen at birth, [12] and 90% of lymphangiomas are evident by 2 years of age. [12]

History

In 1828, Redenbacher first described a lymphangioma lesion. In 1843, Wernher gave the first case report of a cystic hygroma, from the Greek "hygro-" meaning fluid and "oma" meaning tumor. In 1965, Bill and Summer proposed that Cystic hygromas and lymphangiomas are variations of a single entity and that its location determines its classification.[ citation needed ]

Related Research Articles

<span class="mw-page-title-main">Sirolimus</span> Pharmaceutical drug

Sirolimus, also known as rapamycin and sold under the brand name Rapamune among others, is a macrolide compound that is used to coat coronary stents, prevent organ transplant rejection, treat a rare lung disease called lymphangioleiomyomatosis, and treat perivascular epithelioid cell tumour (PEComa). It has immunosuppressant functions in humans and is especially useful in preventing the rejection of kidney transplants. It is a mechanistic target of rapamycin (mTOR) kinase inhibitor that reduces the sensitivity of T cells and B cells to interleukin-2 (IL-2), inhibiting their activity.

<span class="mw-page-title-main">Angioma</span> Benign tumors derived from cells composing or surrounding blood or lymph vessels

Angiomas are benign tumors derived from cells of the vascular or lymphatic vessel walls (endothelium) or derived from cells of the tissues surrounding these vessels.

<span class="mw-page-title-main">Cystic hygroma</span> Human disease

A cystic hygroma is an abnormal growth that usually appears on a baby's neck or head. It consists of one or more cysts and tends to grow larger over time. The disorder usually develops while the fetus is still in the uterus, but can also appear after birth.

<span class="mw-page-title-main">Angiokeratoma</span> Medical condition

Angiokeratoma is a benign cutaneous lesion of capillaries, resulting in small marks of red to blue color and characterized by hyperkeratosis. Angiokeratoma corporis diffusum refers to Fabry's disease, but this is usually considered a distinct condition.

<span class="mw-page-title-main">Vascular tumor</span> Tumor originating from blood or lymph vessels

A vascular tumor is a tumor of vascular origin; a soft tissue growth that can be either benign or malignant, formed from blood vessels or lymph vessels. Examples of vascular tumors include hemangiomas, lymphangiomas, hemangioendotheliomas, Kaposi's sarcomas, angiosarcomas, and hemangioblastomas. An angioma refers to any type of benign vascular tumor.

<span class="mw-page-title-main">Aneurysmal bone cyst</span> Benign bone tumor consisting of blood

Aneurysmal bone cyst (ABC) is a non-cancerous bone tumor composed of multiple varying sizes of spaces in a bone which are filled with blood. The term is a misnomer, as the lesion is neither an aneurysm nor a cyst. It generally presents with pain and swelling in the affected bone. Pressure on neighbouring tissues may cause compression effects such as neurological symptoms.

<span class="mw-page-title-main">Lymphangiomatosis</span> Medical condition

Lymphangiomatosis 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.

<span class="mw-page-title-main">Persistent thyroglossal duct</span> Medical condition

A persistent thyroglossal duct is a usually benign medical condition in which the thyroglossal duct, a structure usually only found during embryonic development, fails to atrophy. The duct persists as a midline structure forming an open connection between the back of the tongue and the thyroid gland. This opening can lead to fluid accumulation and infection, which necessitate the removal of the duct.

A vascular malformation is a type of vascular anomaly. They may cause aesthetic problems as they have a growth cycle, and can continue to grow throughout life.

<span class="mw-page-title-main">Lymphangioma circumscriptum</span> Medical condition

Superficial lymphatic malformation 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. Lymphangioma circumscriptum is the most common congenital lymphatic malformation. It is a benign condition and treatment is not required if the person who has it does not have symptoms from it.

Cobb syndrome is a rare congenital disorder characterized by visible skin lesions and spinal angiomas or arteriovenous malformations (AVMs). The skin lesions of Cobb syndrome typically are present as port wine stains or angiomas, but reports exist of angiokeratomas, angiolipomas, and lymphangioma circumscriptum. The intraspinal lesions may be angiomas or AVMs and occur at levels of the spinal cord corresponding to the affected skin dermatomes. They may in turn produce spinal cord dysfunction and weakness or paralysis.

<span class="mw-page-title-main">Spiradenoma</span> Medical condition

Spiradenomas (SA) are rare, benign cutaneous adnexal tumors that may progress to become their malignant counterparts, i.e. spiradenocarcinomas (SAC). Cutaneous adnexal tumors are a group of skin tumors consisting of tissues that have differentiated towards one of the four primary adnexal structures found in normal skin: hair follicles, sebaceous sweat glands, apocrine sweat glands, and eccrine sweat glands. SA and SAC tumors were regarded as eccrine gland tumors and termed eccrine spiradenomas and eccrine spiradenocarcinomas, respectively. However, more recent studies have found them to be hair follicle tumors and commonly term them spiradenomas and spiradenocarcinomas, respectively. Further confusing the situation, SA-like and SAC-like tumors are also 1) manifestations of the inherited disorder, CYLD cutaneous syndrome (CCS), and 2) have repeatedly been confused with an entirely different tumor, adenoid cystic carcinomas of the salivary gland. Here, SA and SAC are strictly defined as sporadic hair follicle tumors that do not include the hereditary CCS spiradenomas and heridtary spiradenocarcinoms of CCS or the adenoid cystic carcinomas.

<span class="mw-page-title-main">Congenital pulmonary airway malformation</span> Medical condition

Congenital pulmonary airway malformation (CPAM), formerly known as congenital cystic adenomatoid malformation (CCAM), is a congenital disorder of the lung similar to bronchopulmonary sequestration. In CPAM, usually an entire lobe of lung is replaced by a non-working cystic piece of abnormal lung tissue. This abnormal tissue will never function as normal lung tissue. The underlying cause for CPAM is unknown. It occurs in approximately 1 in every 30,000 pregnancies.

A vascular anomaly is any of a range of lesions from a simple birthmark to a large tumor that may be disfiguring. They are caused by a disorder of the vascular system. A vascular anomaly is a localized defect in blood vessels or lymph vessels. These defects are characterized by an increased number of vessels, and vessels that are both enlarged and heavily curved. Some vascular anomalies are congenital, others appear within weeks to years after birth, and others are acquired by trauma or during pregnancy. Inherited vascular anomalies are also described and often present with a number of lesions that increase with age. Vascular anomalies can also be a part of a syndrome.

Lymphohemangioma is a disease characterized by swelling of the lymph nodes and blood vessels. It is variously described as a "mixture of clear fluid and blood-filled cysts", a mass of abnormal swollen veins and lymph nodes, or a tumorous growth of lymph and blood vessels. Oftentimes, it is described as a misnomer for combined lymphatic and capillary malformation. The lymphangiomas are known to be malformations of the lymph tissue, 75% of which is found near the head and neck. However, it can affect any region of the body. This disease is most commonly observed in children and male patients. In fact, Lymphangiomas account for 4% of all vascular tumors and 25% of the benign vascular tumors in children. Additionally, 50% of Lymphangiomas are noted at birth and become more evident by age 5.

<span class="mw-page-title-main">Scrotal ultrasound</span> Medical ultrasound examination of the scrotum.

Scrotalultrasound is a medical ultrasound examination of the scrotum. It is used in the evaluation of testicular pain, and can help identify solid masses.

Stasis papillomatosis is a disease characterized by chronic congestion of the extremities, with blood circulation interrupted in a specific area of the body. A consequence of this congestion and inflammation is long-term lymphatic obstruction (lymphedema). It is also typically characterized by the appearance of numerous papules. Injuries can range from small to large plates composed of brown or pink, smooth or hyperkeratotic papules. The most typical areas where injuries occur are the back of the feet, the toes, the legs, and the area around a venous ulcer formed in the extremities, although the latter is the rarest of all. These injuries include pachydermia, lymphedema, lymphomastic verrucosis and elephantosis verrucosa. The disease can be either localized or generalized; the localized form makes up 78% of cases. Treatment includes surgical and pharmaceutical intervention; indications for partial removal include advanced fibrotic lymphedema and elephantiasis. Despite the existence of these treatments, chronic venous edema, which is a derivation of stasis papillomatosis, is only partially reversible. The skin is also affected and its partial removal may mean that the skin and the subcutaneous tissue are excised. A side effect of the procedure is the destruction of existing cutaneous lymphatic vessels. It also risks papillomatosis, skin necrosis and edema exacerbation.

Fibro-adipose vascular anomaly, also known as FAVA, is a type of vascular anomaly that is both rare and painful. FAVA is characterized by tough fibrofatty tissue taking over portions of muscle, most often contained within a single limb. FAVA also causes venous and/or lymphatic abnormalities.

In CT scan of the thyroid, focal and diffuse thyroid abnormalities are commonly encountered. These findings can often lead to a diagnostic dilemma, as the CT reflects nonspecific appearances. Ultrasound (US) examination has a superior spatial resolution and is considered the modality of choice for thyroid evaluation. Nevertheless, CT detects incidental thyroid nodules (ITNs) and plays an important role in the evaluation of thyroid cancer.

Diffuse capillary malformation with overgrowth (DCMO) is a subset of capillary malformations (CM) associated with hypertrophy, i.e. increased size of body structures. CM can be considered an umbrella term for various vascular anomalies caused by increased diameter or number of capillary blood vessels. It is commonly referred to as "port-wine stain", and is thought to affect approximately 0.5% of the population. Typically capillaries in the papillary dermis are involved, and this gives rise to pink or violaceous colored lesions. The majority of DCMO lesions are diffuse, reticulated pale-colored stains.

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