Sarcoma - Kaposi: Stages

Approved by the Cancer.Net Editorial Board, 08/2023

ON THIS PAGE: You will learn about how doctors describe a cancer’s growth or spread. This is called the stage. Use the menu to see other pages.

What is cancer staging?

Staging is a way of describing where the cancer is located, if or where it has spread, and whether it is affecting other parts of the body.

Doctors use diagnostic tests to find out the cancer's stage, so staging may not be complete until all the tests are finished. Knowing the stage helps the doctor recommend the best kind of treatment, and it can help predict a patient's prognosis, which is the chance of recovery. There are different stage descriptions for different types of cancer.

For classic, endemic, and acquired Kaposi sarcoma, there are no official staging systems. Instead, the health care team develops a treatment plan based on the individual's specific situation. This may include whether the disease is growing and spreading, if the sarcoma has spread to organs, how well the immune system is functioning, and other factors.

For epidemic Kaposi sarcoma, there is also no official staging system. However, in 1988 the AIDS Clinical Trials Group (ACTG) developed a staging system called the TIS system. The ACTG is the largest human immunodeficiency virus (HIV) clinical trials organization in the world and is funded by the U.S. National Institutes of Health. The treatment of HIV has changed a lot since 1988. Therefore, it is unclear if the TIS system is still clinically useful.

The TIS system evaluates:

  • Tumor (T): The size of the tumor.

  • Immune system (I): The status of the immune system, which is measured by the number of a specific type of white blood cell, called a CD4 cell, in the blood.

  • Systemic illness (S): The spread of the disease throughout the body or the presence of HIV-related or acquired immune deficiency syndrome (AIDS)-related systemic illness.

Within each of the 3 parts of the system, there are 2 subgroups: good risk (0, zero) or poor risk (1).

The following table has been adapted from the original system, which was developed by the ACTG to illustrate the TIS system.

Good Risk (0)

(Any of the following)

Poor Risk (1)

(Any of the following)

Tumor (T)

Only located in the skin and/or lymph nodes and/or minimal oral disease (Flat lesions confined to the palate or roof of the mouth)

Tumor-associated edema (fluid buildup) or ulceration (break in the surface of the skin)

Extensive oral Kaposi sarcoma

Gastrointestinal Kaposi sarcoma

Kaposi sarcoma in other organs in the body

Immune system (I)

CD4 cell count is 200 or more cells per cubic millimeter

CD4 cell count is less than 200 cells per cubic millimeter

Systemic illness (S)

No systemic illness present

No “B” symptoms, which include unexplained fever, night sweats, unexpected weight loss of more than 10%, or diarrhea for more than 2 weeks

A Karnofsky Performance Status score of 70 or higher (see below)

History of systemic illness and/or thrush

One or more “B” symptoms are present

A Karnofsky performance status of less than 70

Other HIV-related illness is present, for example, neurological disease or lymphoma

The Karnofsky Performance Status scale measures the ability of people with cancer to perform ordinary tasks. For example, people with a score of 70 can take care of themselves but are unable to carry on normal activity or active work. People with a score of less than 70 are unable to care for themselves.

Recurrent. Recurrent cancer is cancer that has come back after treatment. If there is a recurrence, the cancer may need to be staged again (called re-staging) using the system above.

Information about the cancer’s stage will help the doctor recommend a specific treatment plan. The next section in this guide is Types of Treatment. Use the menu to choose a different section to read in this guide.