Kaposi Sarcoma

Kaposi Sarcoma

Key Points
Disease of the blood vessels
Typically caused by infection with kaposi sarcoma herpes virus
Increased prevalence with the advent of HIV disease
Consists of red or purple spots and bumps anywhere on the skin or mucous membranes, initially small and not accompanied by pain

Kaposi sarcoma is rare disease of the blood vessels, which has become more common with the advent of HIV, though improvements in HIV drugs have made it a less frequent condition. It typically consists of red or purple spots and bumps, which may appear anywhere on the skin or mucous membranes. Lesions are initially small and not accompanied by pain, but may ulcerate as the condition progresses and cause pain. It typically begins as flat lesions on the lower leg, and may be associated with lymphodema. These initial lesions may progress into plaques, bumps or tumors with a scaly appearance. Lesions, may also form internally, affecting the lungs, genitals, lymphatic system and other areas, and may lead to other complications such as difficulty swallowing, bleeding, breathing difficulty, and swelling.

There are four subtypes of kaposi sarcoma. The classic form of the condition affects elderly men of middle European, sub-Saharan African, or Mediterranean background. Endemic kaposi sarcoma is seen in parts of Africa and affects children and young adults, and the number of cases are rising with the rate of HIV infection. Iatrogenic kaposi sarcoma results from drug treatments which cause immune system suppression, and should especially concern persons who have undergone organ transplant. HIV-related kaposi sarcoma typically affects persons infected with HIV, with the condition being more common in men in the US, and women in Africa.

Kaposi sarcoma is typically caused by infection with kaposi sarcoma herpes virus. The virus is usually transmitted sexually, but it is thought that there may be non-sexual methods of transmission as well. The condition may also be caused by genetic or hormone factors, or the body's production of certain proteins which signal cells. When not related to HIV, the condition is extremely rare. The condition may be dormant, but it may also begin replication, causing the presentation of symptoms. Additionally, the virus may also be responsible for some forms of non-Hodgkin lymphoma, as well as Casteleman disease. It is variably classified as cancerous and reactive hyperplasia, which may be either multicentric or metastatic.

Differential Diagnosis (Other conditions with similar appearance)
Basal cell carcinoma, Eyelid
Blepharitis, Adult
Cellulitis, Orbital
Hemangioma, Cavernous
Hordeolum
Subconjunctival Hemorrhage

Diagnosis
Key Points
Diagnosis based on characteristic appearance of lesions
Skin biopsy will be performed to confirm diagnosis and rule out other conditions
Other testing may be performed to rule out association with other conditions (HIV)

Treatment
Treatment is predicated on severity of lesions and presence of associated conditions
In localized cases, treatment typically consists of removal or destruction through various therapies
Internal or severe cases may be treated with a variety of therapies, including chemotherapy

The treatment of kaposi sarcoma is often predicated on the severity of lesions and the presence of associated conditions. In cases associated with HIV infection, treatment of the associated condition with HIV medications may alleviate symptoms and prevent further lesion formation due to the improvement of immune function accomplished by these drugs. Additionally, in cases of iatrogenic kaposi sarcoma, ceasing intake of immunosuppressants may resolve the condition.

In other cases, treatment is based on the severity of lesions. Localized lesions may be treated with a number of therapies, including cryotherapy, radiotherapy, surgical excision, laser therapies, topical alitretinoin, and Injections of anti-cancer medications. These treatments should only be pursued if lesions become painful or cosmetically troublesome. Lesions may recur after treatment. In severe or internal cases, more aggressive treatments may be required. These treatments typically consist of the administration of anti-cancer drug cocktails, chemotherapy, and immunotherapy.