Overview
Kaposi Sarcoma is a disease in which cancer cells are found in the skin or mucous membranes lining the gastrointestinal tract, from mouth to anus, including stomach and intestines. Kaposi Sarcoma is caused by the human herpesvirus 8, also known as Kaposi sarcoma-associated herpesvirus (KSHV) or human herpes 8.
Associated Anatomy of Kaposi Sarcoma
Kaposi Sarcoma usually affects the gastrointestinal system.
Kaposi Sarcoma Causes
Human herpesvirus 8 Infection: The underlying cause for Kaposi Sarcoma is an infection with human herpesvirus 8, also known as Kaposi sarcoma-associated herpesvirus (KSHV) or human herpes 8. It belongs to the same family as the Epstein-Barr virus; how the virus is acquired and spread is not clearly understood.
In healthy people, HHV-8 infection usually causes no symptoms because the immune system is robust enough to keep it under control. HHV-8 may trigger Kaposi sarcoma in those with weakened immune systems.
Kaposi Sarcoma Symptoms
Symptoms and signs of Kaposi Sarcoma include:
- Lumps: A noticeable lump or swelling, a lump that is increasing in size or painful, recurrence of a lump that has been removed.
- Pain: Especially if a tumor is pressing on nerves or muscles.
- Bumps: Slightly elevated purple, pink, brown, black, blue, or red blotches anywhere on the skin or in the mouth or throat.
- Lymphedema: Swelling in the neck region caused by blockage of the lymphatic system.
- Unexplained stomach pain or chest pain: Especially in the stomach or chest. Additionally, one may experience unexplained coughing.
- Diarrhea: Caused by lesions in the gastrointestinal tract.
Kaposi Sarcoma Diagnosis
There are a few diagnostic tests for Kaposi Sarcoma. Biopsy may be done on skin lesions to determine if it is Kaposi Sarcoma.
Blood Test
Fecal occult blood test may be done to detect hidden blood in stool.
Chest X-ray
A chest X-ray may be done to reveal abnormalities, if any, in the lungs.
Bronchoscopy
A bronchoscopy will help examine the lining of the nose, mouth, and lungs.
Endoscopy
An endoscopy may be performed to examine the esophagus, stomach, and first part of your small intestine.
Colonoscopy
Colonoscopy may be done to examine the walls of the rectum and colon.
Kaposi Sarcoma Stages
The TIS staging system is usually used for those with Kaposi Sarcoma.
- T (Tumor status): Extent of the Tumor in the body.
- I (Immune system status): Health of the immune system, measured by the CD4 cell count using a blood test.
- S (Systemic illness status): Extent of Systemic illness in the body, meaning how sick the HIV or Kaposi Sarcoma is making the person
Doctors also do a further staging:
Tumor status
- T0: The disease is only in the skin, only in the lymph nodes, or in both. Lesions appear flat and mostly on the roof of the mouth.
- T1: Lesions are widespread, and there may be swelling or sores in the mouth as well as raised lesions in other organs such as the liver, intestines, stomach, or lungs.
Immune system status
- I0: CD4 cell count is 200 or more per cubic millimeter.
- I1: CD4 cell count is less than 200 cells per cubic millimeter.
Systemic illness status
- S0: No history of other infections due to a weakened immune system (opportunistic infections) or of fungal infection of the mouth. There is also no unexplained fever, weight loss of more than 10%, or diarrhea lasting for at least 2 weeks (collectively called the B symptoms).
- S1: Here, there is a history of opportunistic and fungal infections or another HIV-related disease. Additionally, B symptoms are exhibited, and there is a limited ability to do daily tasks.
Kaposi Sarcoma Treatment
Treatment for Kaposi sarcoma includes:
Antiviral drug therapy
AIDS-related Kaposi sarcoma is more serious than the classic or transplant-related disease. Antiviral drug combinations are used here.
Surgery for Kaposi Sarcoma Treatment
Minor surgery (excision), burning (electrodesiccation), or freezing (cryotherapy) are sometimes used.
Radiation Therapy
Radiation Therapy - Low-dose radiation is helpful for lesions in the mouth and multiple skin lesions.
Chemotherapy
Injection of the chemotherapy drug vinblastine directly into lesions is sometimes done. When there are more than 25 lesions present, chemotherapy with standard anti-cancer drugs may be helpful. Chemotherapy is also used to treat the disease in the lymph nodes and digestive tract.
Risk Factors of Kaposi Sarcoma
Kaposi Sarcoma is caused by an infection with the human herpesvirus 8. However, all who are infected may not have the disease.&
- Weak immune system: The cancer is usually triggered by a weakened immune system on account of age, being HIV-positive, or receiving an organ transplant.
- Sexual activity: Those who have unprotected sex are at a higher risk due to greater chances of HIV and HHV-8 infection. Additionally, men involved in sexual activity with other men are more at risk than those who are only intimate with women.
Complications of Kaposi Sarcoma
Possible complications of Kaposi Sarcoma include:
- Lymphedema: Swelling in the neck region caused by blockage of the lymphatic system
- Secondary localized skin infections
- Cough (possibly bloody)
- Shortness of breath if the disease is in the lungs
- Painful swelling in the legs
- An aggressive form of endemic Kaposi Sarcoma can spread to the bones.
Kaposi Sarcoma Preventions
Primary Prevention of Kaposi Sarcoma
Although there is no proven way to completely prevent the disease, the risk for Kaposi Sarcoma can be lowered by avoiding the known risk factors for HIV/AIDS, such as having unprotected sex and using intravenous needles that have been used by someone else. Kaposi Sarcoma also rarely occurs in people where HIV/AIDS is well controlled.
Secondary Prevention of Kaposi Sarcoma
Prevention would involve safe sexual practice and avoiding other known risk factors for HIV/AIDS, such as using intravenous needles that have been used by someone else. Secondary prevention includes antiviral drug therapy, surgery, radiation, and chemotherapy.
Epidemiology of Kaposi Sarcoma
Kaposi Sarcoma is known as AIDS-defining cancer. Studies have found the overall incidence of the disease to be 481.54 per 100 000 people. HIV-infected men who have sex with men recorded the highest incidence. The incidence was also found to be lower among women.
Expected Prognosis of Kaposi Sarcoma
Kaposi Sarcoma is treatable, and most people respond to treatment. The five-year relative survival is about 72%.
Natural Progression of Kaposi Sarcoma
The TIS staging system is usually used for those with Kaposi Sarcoma, where T indicates the extent of tumor; I indicates the health of the Immune system, and S indicates the extent of Systemic illness in the body. Kaposi Sarcoma is treatable. The five-year relative survival is about 72%.
Pathophysiology of Kaposi Sarcoma
Kaposi sarcoma is caused by the proliferation of spindle cells of endothelial cell origin. The tumors are predominantly composed of KSHV genomic material with immunohistochemical markers of lymphoid, spindle, and endothelial cells.