Kaposi sarcoma (KS) often appears as discolored tumors on the skin or oral mucus membrane. As multiple lesions typically occur at the same time, it may be difficult for doctors to detect this cancer early.

The cause of KS is the human herpesvirus 8 (HHV-8).

Therefore, doctors most often identify KS in people with a compromised immune system, particularly those living with HIV and AIDS or organ transplant recipients.

In healthy individuals, HHV-8 infection usually causes no symptoms.

Four types of KS affect different populations. Unlike other cancers, there is no officially accepted system for staging KS.

However, in AIDS-related KS, doctors use the AIDS Clinical Trials Group system that considers the extent of the tumor, immune system status, and extent of systemic illness.

This article considers early KS, its symptoms, and treatments.

A dermatologist looking for early signs of Kaposi sarcoma. -1Share on Pinterest
Irina Efremova/Stocksy

KS often starts as flat patches on one or both lower legs. Often people also present with lymphedema, swelling from lymph fluid. As the disease progresses, more patches can form elsewhere, including on the face, hands, mouth, and neck.

Even when a person has only one visible skin lesion, they may already have other areas of KS that are too small to be visible. Therefore, it may be challenging to find KS early.

The condition progresses through three distinct stages: patch, plaque, and nodular. In the early patch stage, the lesions are less obvious, flatter, and may be mistaken for bruises or other skin conditions.

Some characteristics of the early skin patches include:

  • Color: The patches can range in color from slightly discolored to purple, brown, or black.
  • Size: Initially, the patches are small, measuring less than 1 centimeter in diameter. However, they can grow in size over time.
  • Shape: The patches may be oval-shaped, circular, or irregular. They may have well-defined edges or be diffuse and merge with the surrounding skin.
  • Texture: KS patches may be slightly raised and nodular or smooth. Some patches can feel uneven, scaly, or have a bumpy texture.

In some cases, the patches can become ulcerated and bleed.

Learn more about how these lesions might look.

The KS-associated herpesvirus(KSHV), also known as HHV8, causes KS. This virus is related to the Epstein-Barr virus (EBV), which is responsible for infectious mononucleosis (mono) and some other forms of cancer.

When someone has KS, KSHV infects the cells lining the blood and lymphatic vessels. The virus causes the cells to divide uncontrollably and to live longer than usual. It can also trigger the cells to form new blood vessels and increase the production of inflammatory substances. These changes may eventually turn the cells cancerous.

Although KSHV infection causes KS, most people who contract the virus do not experience symptoms. It can develop due to many factors, including in people that have the following:

Certain groups have an increased risk of developing KS.

Risk factors may depend on the type of KS.

  • Classic KS: This affects males to females at a 17:1 ratio. It also occurs primarily in people over 50 of Eastern European and Mediterranean descent.
  • AIDS-related KS: This often occurs in people with HIV with CD4 counts less than 200 cells/mm3. It is an AIDs-defining disease, meaning it is a sign that someone has AIDS.
  • African cutaneous KS: This is common in areas of Central and Eastern Africa, with an increase in cases seen in children. About 80% of the population shows signs of KSHV infection in some areas of Africa. KS is the most common cancer in men and the second most common cancer in women in Uganda and Zimbabwe.
  • Immunosuppression-related KS: This affects organ transplant recipients and people taking immunosuppressant drugs. Over 5% of transplant recipients patients who develop cancer following a transplant develop KS, which is a 400- to 500-fold increased risk over the general population.

People living with HIV may benefit from regular testing for KS, specifically by a specialist that can recognize the condition and provide treatment.

Doctors can treat KS, but detecting the disease in its early stages is critical. Early treatment can significantly reduce symptoms and prevent the cancer from progressing.

Treatments vary depending on:

  • type of KS
  • location of KS
  • stage of the disease

Common treatments include:

  • Highly active antiretroviral therapy (HAART): This is a combination of drugs that reduce the effect that HIV has on the immune system.
  • Radiation therapy: This uses high-energy rays to kill cancer cells.
  • Surgery: Doctors may use surgery may be used to remove small KS lesions.
  • Cryosurgery: This uses instruments to deliver extreme cold to freeze and kill cancer cells.
  • Chemotherapy: This involves using drugs that kill cancer cells.
  • Immunotherapy: This boosts the body’s own immune system to help treat cancer.

KS is a type of cancer that usually occurs in people with weakened immune systems. It causes discolored patches on the skin, which can become ulcerated.

It is important to detect KS early as doctors can use various treatments to reduce symptoms and prevent the cancer from progressing. These treatments include HAART, radiation therapy, surgery, cryosurgery, chemotherapy, and immunotherapy.