• Kaposi sarcoma (KS) is an indolent angio-proliferative spindle-cell tumor derived from endothelial and immune cells infected with human herpes virus type 8 (HHV-8)[1]
• It is a multifocal neoplasm
• This is a systemic angiomatosis of malignant evolution which is primarily manifested as multiple vascular nodules in the skin and the organs
• It was first described by Moritz Kaposi, a Hungarian dermatologist in 1872[2]
• It is the most common malignancy in HIV patients
• It is identified as AIDS defining illness

• Etiology:
  • HHV8
  • Sustained by cytokines and growth factors
  • It leads to angioproliferation especially in skin.
  • HIV is a predisposing factor to KS.
  • It spreads mainly through saliva, such as during sexual contact or in interactions between a mother and child.
  • People with healthy immune systems can carry the virus without any problems. But it triggers cancers in people with weakened immune systems

• Pathology:
  • HHV-8 invades endothelial cells causing lytic and/or latent infection of the spindle shaped endothelial cells
  • Endothelial cells infected with HHV8 undergo altered lymphatic differentiation and manufacture cytokines creating a favorable environment for angiogenesis
  • Spread to viscera by dissemination of the involved lymph nodes

• Epidemiology and survival rate:
  • It occurs more in men.
  • HIV-1 associated Kaposi’s sarcoma has a high occurrence in homosexual men of over 30%. Overall, almost 75% of people who have KS live at least 5 years after diagnosis. If the cancer hasn’t spread, about 82% live at least 5 more years. In people whose cancer has spread to nearby areas, the 5-year survival rate is 60%. The rate is 38% if the cancer has spread farther away

• Origin: Endothelial cells

• Clinical:
  • Early lesion – Blue flat macule
  • Late lesion – Nodular red blue mass

Picture

• Types:

	Epidemiology	Age	Site	Prognosis
Classical	Mediterranean	Old men	Skin Lower extremities	Fair prognosis
Endemic	Africa	Children and adults	Skin Extremities	Fair prognosis
Immunodeficiency	HIV and transplant patients	Young adults	Skin Mucosa Internal organs	Poor prognosis

• Diagnosis:
  • P24 ELISA
  • Viral load
  • CD4 count
  • CD4 : CD8
  • PCR
  • HHV8 immunohistochemistry

• Histology: Neoplastic proliferation of endothelial cell origin

• Management:
  • The chemotherapy most commonly used for KS is Interferon alpha with didanosine for slowly progressive disease.
  • Radiation therapy-for skin lesions.
  • In AIDS-related Kaposi’s sarcoma, the first step in treatment is to start or switch to an antiviral drug (ART) combination that will reduce the amount of the virus causing AIDS.
  • EG. Chemotherapeutic drugs (Doxorubicin and paclitaxel) with ART.
  • Although, KS remains to be controlled than cured.
  • Sclerotherapy eg alcohol, propanol, Vinca-alkaloids

• Prevention:
  • There’s no vaccine to protect against HHV-8.
  • Avoid unprotected sex.
  • Avoid injecting drugs with used needles.
  • Medications called pre-exposure prophylaxis can also make you less likely to get HIV.
  • If you have HIV, antiretroviral therapy (ART) should prevent KS, especially if you start it when your CD4 count is still high. If you’ve had an organ transplant, some anti-rejection drugs can also lower your chance of getting KS