Type and Causes of Kaposi’s sarcoma

The Kaposi’s sarcoma is a malignant tumor that can occur especially on the skin, but also on mucous membranes and internal organs such as the bowel. Characteristic are brownish, nodular lesions that usually appear first on the legs. Kaposi’s sarcoma is most common in the context of a weakened immune system (immune-suppression) and infection with the human herpesvirus type 8 (HHV-8). Men are affected often more than women.

Who is at risk of Kaposi’s sarcoma?

An HIV-infected person has a 20,000 times increased risk of developing Kaposi’s sarcoma as compared to to a person without HIV. In the early 1990’s there were approximately 47 cases per million people per year among the HIV infected individuals of United States.

With the advent of anti-HIV drugs the numbers have fallen and it now occurs at a rate of about 7 cases per million people each year.

The rates are highest in Africa where Kaposi’s sarcoma herpesvirus (KSHV) (also known as human herpesvirus type 8 – HHV-8) and HIV infection rates are high. About 1 in 200 transplant patients in the United States gets Kaposi’s sarcoma.

Type and Causes of Kaposi’s sarcoma

HIV-associated (epidemic) Kaposi’s sarcoma:

The HIV-associated Kaposi’s sarcoma can occur both as an early sign of HIV infection, as well as a late symptom in the course of highly immune compromised AIDS. This form is very aggressive and attacks the mucous membranes, internal organs and skin of the arms and legs. It may also affect nose, ears, eyelids or the glans of the penis. Typical there are reddish-purple spots, which can be converted into hard nodules. Earlier, the HIV-associated Kaposi’s sarcoma was observed in approximately one third of people with HIV infection. Since the introduction of highly active antiretroviral therapy (HAART abbreviated) in mid-1990s, it has become rare (about five to seven percent of people with HIV infection).

Kaposi’s sarcoma by iatrogenic immune-suppression

After organ transplantation and in the treatment of several chronic inflammatory diseases, the immune system needs to be weakened by medication (iatrogenic immunosuppression). As in HIV disease, a weakened immune system favors the formation of a Kaposi’s sarcoma. After cancellation or reduction of immune-suppression, it forms in some cases all the way back.

Chronic (classical) Kaposi’s sarcoma

The chronic Kaposi sarcoma is rare. It occurs mainly in older men in Eastern Europe and Italy. It initially developed solely by the leg and the foot. In the course of the disease, it can spread to internal organs. This form is usually not very aggressive.

African endemic Kaposi’s sarcoma

The endemic Kaposi’s sarcoma occurs in tropical regions of Africa, where it is very common. Especially children and young people are affected by this form. This form is not very aggressive. In rare cases the endemic Kaposi’s sarcoma progresses rapidly to death.

Symptoms of Kaposi’s sarcoma

Nodes such as increased or patchy flat spots on the skin. These are red, purple, brown or black. These are usually the first symptoms of Kaposi’s sarcoma. The lesions can develop quickly and increase in size.

However, there is a single region at the beginning, it is possible to display for more. Often, the lesions lead to form a larger tumor. These are most commonly seen on the face around the mouth, ears and nose. Lesions are frequently seen also on the legs and feet and genitals.

In the dark skinned individuals, the lesions are characterized as dark brown or black.

Lesions are similar to those on the skin sometimes tonsils, visible on the palate (roof of the mouth) or under neck or on mucous membranes, especially in the mouth, nose, gums, tongue.

The lesions are usually painless and not itchy. They can be painful when there is inflammation or swelling.

There may be a superimposed or secondary bacterial infection on the skin lesions. Since the patient usually has lowered immunity, there is also a risk of secondary infection of other organs such as lung (eg pneumonia) etc ..

Some aggressive tumors can spread to other organs. If the distribution is in the lungs than there are respiratory associated symptoms. In the case of liver metastasis, there are signs of liver damage such as jaundice etc.

Lesions in the esophagus (food pipe) or the respiratory system may grow to hinder feeding or breathing.

Lung affection can lead to difficulty in breathing, blood in the sputum and shortness of breath, gastrointestinal tract affection can cause bleeding (which can be fatal) and suffering of the lymphatic channels leading to swollen lymph nodes and lymph vessels. Lesions in the gastrointestinal tract can cause nausea, diarrhea, bleeding with stools and vomiting in some people.

Over a long period, the bleeding can lead to anemia. This is caused by decrease in the number of red blood cells.

Diagnosis of Kaposi’s sarcoma

In the early stages when there are only reddish spots, the clinical diagnosis can be difficult. In these cases, histological examination is crucial.  The clinical diagnosis should always be confirmed histologically.

The diagnosis is made at an advanced stage of the typical lesions. To detect the disease as early as possible, histological studies as well as imaging of the chest, the abdomen and the lymph nodes are implemented and applied. These include x-rays and ultrasounds and digestive colonoscopies. The Kaposi’s cells may also be detected in the blood.

Treatments of Kaposi’s sarcoma

Since the Kaposi’s sarcoma often occurs in patients whose immune systems are already weakened, so measures must be taken that do not weaken the immune system further in the treatment of Kaposi’s sarcoma.

For this reason, in HIV and AIDS patients usually called antiviral combination therapy isapplied for the treatment of Kaposi’s sarcoma, which is also used for the treatment of HIV and AIDS. Here, patients receive three different antiretroviral drugs, which are also abbreviated ARV. The antiretroviral drugs cause to regress the symptoms of Kaposi’s sarcoma continuously.

Also in case of transplant patients, must be taken to ensure that the immune system is not weakened further. In addition, depending on the patient condition other therapy methods are also used for treatment of Kaposi’s sarcoma . In early stages, laser or radiation treatments and excisions or other physical therapies are also used to treat it. In some cases, the use of a chemotherapy is also necessary for a successful treatment of Kaposi’s sarcoma.