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Cancer-like disease that can be genetically transmitted or acquired, in association with Acquired Immunodeficiency Syndrome (AIDS). It is a dermatologic tumor caused by infection with human herpesvirus 8 (HHV8). The erythematous to violaceous cutaneous lesions can either be macular, patch, plaque, nodular, or exophytic. The cutaneous lesions can be solitary, localized, or disseminated. It can involve the oral cavity, lymph nodes, and viscera.
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Kaposi Tumor; Kaposi Malignancy; Multiple Idiopathic Pigmented Hemangiosarcoma.
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Idiopathic multiple pigment sarcoma described initially in 1872 by the Hungarian dermatologist Moritz Kaposi (1837-1902) practicing medicine at the University of Vienna. It became more widely known as one of the AIDS-defining illnesses in the 1980s. The viral cause for this cancer was discovered in 1994.
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There are four subtypes that have been described:
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Classic Kaposi Sarcoma: Affects middle aged men of Mediterranean descent. It tends to be indolent, presenting with erythematous or violaceous patches on the lower extremities.
African Endemic Kaposi Sarcoma: The lesions tend to be more aggressive and disseminated.
Kaposi Sarcoma: Iatrogenic consequences observed in immunosuppressed patients.
AIDS-Related Kaposi Sarcoma: Lesions that often rapidly progress to plaques and nodules and affecting predominantly the upper trunk, face, and oral mucosa. The diagnosis can be made with a tissue biopsy and, if clinically indicated, internal imaging should be done. AIDS was first described in 1981 in adults and the causative agent was first isolated in 1983. According to the United Nations report on AIDS in 2007, about 33 million people were living with human immunodeficiency virus (HIV) and around 2.7 million were newly infected. Developing nations like India has about 2.5 million people infected with the virus.
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Varies dramatically according to geography. Most common AIDS-associated malignancy in the United States: 73,000-fold more frequent in homosexual HIV-infected men than in the general population; in other HIV-transmission groups, Kaposi sarcoma (KS) affects 1 to 3% of persons other than male homosexuals (however, there is a 10,000-fold increase in HIV-infected women and nonhomosexual men). Two times more frequent in white population men than in black population men.
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Rare autosomal dominant forms (rarely familial); mostly acquired (associated with herpesvirus 8 infection in AIDS patients, but overexposure to nitrite might be an alternate cause).
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Formed by proliferation of abnormal vascular endothelial cells. This has been established by histochemical demonstration of factor VIII-related antigen in both the cells lining the vascular channels and in the spindle-cell component of both classic and AIDS-related Kaposi sarcoma. The tumors appear in a multicentric fashion, although metastatic lesions may develop. The cutaneous distribution is occasionally symmetrical and tends to follow the path of superficial veins.