Kaposi sarcoma is a cancer that causes skin blotches and tumors. It has three skin stages, and the patch stage is one of them.
The human herpesvirus 8 (HHV8) causes Kaposi sarcoma. HHV8 may be transmitted during sex, through saliva, or during birth.
HHV8 is a common virus. Most people who have it will not develop Kaposi sarcoma. The virus tends to cause cancer in people with weakened immune systems.
Endothelial cells are the cells that line the lymph and blood vessels. In people with Kaposi sarcoma, endothelial cells divide too many times, live too long, and develop new blood vessels. They also produce excess amounts of chemicals that cause inflammation.
Over time, these changes can turn endothelial cells into cancer cells.
In this article, we examine the patch stage of Kaposi sarcoma. We discuss the characteristics of the stage and how doctors diagnose and differentiate it from other conditions with similar symptoms. We also look at treatments and the outlook for this stage of the disease.
Kaposi sarcoma typically manifests as lesions or tumors on the skin or the moist lining of organs and body cavities, such as inside the mouth. It can also develop in other areas, such as the lungs, digestive tract, or lymph nodes.
The patch stage of Kaposi sarcoma is the earliest phase of the condition. The signs and symptoms depend on whether a person has Kaposi sarcoma lesions externally or internally.
Lesions on the skin occur more often than internal lesions. They commonly first appear as spots on the legs or face.
Early patch stage Kaposi sarcoma lesions typically have the following characteristics:
- multiple lesions
- flat and not raised above the surrounding skin
- asymmetrical distribution
- varying sizes
- differing color, including red, pink, purple, brown, or blue areas of skin discoloration (macules)
- thickened or hardened areas of soft tissue, specifically the skin
Patch stage lesions are initially small and flat and do not cause itching or pain. Their appearance resembles bruises but does not lose color with pressure.
Doctors diagnose Kaposi sarcoma in the patch stage using the
- Medical history: A doctor will ask about a person’s symptoms and other preexisting conditions. People with weakened immune systems, such as people with HIV or organ transplant recipients taking immune system-suppressing drugs, have a
higher riskof Kaposi sarcoma.
- Physical examination: A doctor will evaluate the characteristics of the lesions and the areas of the body they affect.
- HIV test: A doctor may order blood or saliva testing for HIV, such as antigen tests, antibody tests, and nucleic acid tests.
- Biopsy: A healthcare professional takes a small tissue sample, called a biopsy, from the lesion for a laboratory to check. A pathologist can diagnose Kaposi sarcoma by observing the cells in the sample under a microscope.
- Imaging tests: A healthcare professional may use an X-ray or CT scan to screen the lungs for pulmonary Kaposi sarcoma, especially if people have breathing difficulties.
- Bronchoscopy: This test lets doctors see inside the windpipe and large airways of the lungs to check for Kaposi sarcoma.
- Gastrointestinal endoscopy: Doctors may use tests such as an upper endoscopy, colonoscopy, and double balloon enteroscopy if they suspect Kaposi sarcoma in the stomach or intestines.
- Patch stage: Lesions are flat and not raised above the surrounding skin.
- Plaque stage: The lesions are flat but slightly raised.
- Nodule stage: The lesions turn into bumps on the skin, known as nodules.
Skin lesions can evolve from a patch in the early stages of the disease to a plaque and, over time, to an ulcerating tumor nodule.
Lesions can vary in size and quantity, ranging from one lesion under 1 centimeter in diameter to more than 100 plaques across the skin’s surface.
The lesions in the patch stage of Kaposi sarcoma can be subtle and mimic several inflammatory skin disorders. However, the plaque stage exhibits the characteristic lesion appearance of Kaposi sarcoma more clearly, such as widespread blood vessel growth through the middle layer of skin, called the dermis.
Kaposi sarcoma can appear rash-like in the early stages. People may initially mistake it for other inflammatory skin conditions.
Specific conditions can cause lesions that
- Acquired tufted angiomas: These are
rarebenign tumors composed of a collection of blood vessels. They develop on the skin and underlying tissues on the legs, arms, and upper trunk.
- Acroangiodermatitis: This rare benign condition presents as purple patches on the skin that usually appear on the legs.
- Cutaneous angiosarcoma: This
rarecancer starts in the inner lining of lymph and blood vessels. It causes skin lesions that may ulcerate and bleed.
- Fibrosarcomatous dermatofibrosarcoma protuberans: This rare cancer causes tumors in the deep skin layers. It is likely to metastasize, or spread.
- Granuloma annulare: This benign skin condition
results ina ring-like rash on the hands and feet.
- Kaposiform hemangioendothelioma: This
rarebenign tumor grows in the blood vessels just under the skin. It can also grow inside the abdomen or chest.
Treating patch stage Kaposi sarcoma
- type of Kaposi sarcoma
- number of lesions and their location
- a person’s overall health
- problems the condition is causing
During the patch stage, when people have a few skin lesions, doctors may use the following treatments:
- Radiation therapy: Radiation therapy is effective at treating lesions on the skin or near the surface of the body. Electron-beam radiation therapy
can treatKaposi sarcoma lesions on the skin. Photon radiation can penetrate deeper areas of the body and treat lesions in the mouth or throat.
- Cryosurgery: Healthcare professionals apply liquid nitrogen to the affected area to freeze and kill the cells. This treatment can be helpful for small lesions on the face but not large or deep lesions.
- Topical treatment: This treatment involves applying the medication, such as a retinoid drug, directly to the patches. Topical retinoids are helpful for treating a few visible lesions but do not treat widespread lesions or stop new lesions from forming. People can also apply imiquimod cream
three times per weekfor 24 weeks to treat Kaposi sarcoma lesions.
- Surgery: Excision or curettage and electrodesiccation can remove small lesions.
- Chemotherapy: Doctors may use chemotherapy drugs, such as liposomal anthracyclines or paclitaxel, for widespread lesions or when Kaposi sarcoma affects the lymph nodes, lungs, and digestive tract.
- Intralesional chemotherapy: This is chemotherapy injected directly into the Kaposi sarcoma lesions.
For people with AIDS, doctors will focus on treating the late stage HIV infection using anti-HIV drugs. The lesions may get smaller as a person’s immune function improves.
Some people may only require highly active antiretroviral therapy (HAART) to treat Kaposi sarcoma.
Patch stage lesions sometimes improve without treatment when people with organ transplants switch immune system-suppressing drugs.
Doctors may recommend using sirolimus instead of another anti-rejection medication. Sirolimus can reduce Kaposi sarcoma lesions.
Many doctors do not advise chemotherapy for organ transplant recipients.
Kaposi sarcoma is a treatable disease with a positive outlook. Few people die from the condition because it typically responds well to treatment.
According to the
This means people with patch stage Kaposi sarcoma are around 81% as likely as people without the cancer to live for at least 5 years after their diagnosis.
The 5-year relative survival rate is 75% for all stages of Kaposi sarcoma combined.
Kaposi sarcoma is a cancer that develops from endothelial cells. There are three skin stages of Kaposi sarcoma: patch, plaque, and nodule. Each stage progresses in severity.
During the patch stage, Kaposi sarcoma lesions are flat and appear as skin discoloration or spots in various colors. The lesions are typically not painful or itchy in the early stages of the disease. They may resemble other inflammatory skin conditions.
As the condition progresses, the lesion may become larger, more widespread, and turn into slightly raised plaques or nodules.
Doctors can treat the patch stage of Kaposi sarcoma in several ways depending on its type and severity. For example, using surgery, topical medications, or other treatment modalities.
People with patch stage Kaposi sarcoma have a positive outlook, with a 5-year relative survival rate of