Sarcoma, Soft Tissue - Stages and Grades

Approved by the Cancer.Net Editorial Board, 05/2016

ON THIS PAGE: You will learn about how doctors describe a cancer’s growth or spread, and how quickly it may grow. This is called the stage and grade. To see other pages, use the menu.

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 of the tests are finished. Knowing the stage helps the doctor to decide what kind of treatment is best and can help predict a patient's prognosis, which is the chance of recovery. There are different stage descriptions for different types of cancer.

There are several systems used to describe the stage of sarcoma. These systems are somewhat different from each other, but all use an overall stage to help predict a person’s prognosis.

TNM staging system

One tool that doctors use to describe the stage is the TNM system. Doctors use the results from diagnostic tests and scans to answer these questions:

  • Tumor (T): How large is the primary tumor? Where is it located?

  • Node (N): Has the tumor spread to the lymph nodes? If so, where and how many?

  • Metastasis (M): Has the cancer metastasized to other parts of the body? If so, where and how much?

The results are combined to determine the stage of cancer for each person. There are 4 stages: stages I through IV (1 through 4). The stage provides a common way of describing the cancer, so doctors can work together to plan the best treatments.

Here are more details on each part of the TNM system for sarcoma:

Tumor (T)

Using the TNM system, the "T" plus a number (0 to 2) and letter (a or b) is used to describe the size and location of the tumor.

The tumor (T) is further described by its depth. The tumor depth is described as either superficial or deep. The tumor depth is described as superficial when the tumor is above the body's superficial tissue. It is described as deep when the tumor is beneath the body's superficial tissue or has grown into the deep tissue. Specific tumor stage information is listed below.

TX: The primary tumor cannot be evaluated.

T0: There is no evidence of a primary tumor.

T1: The size of the tumor is 5 centimeters (cm) or smaller.

T1a: The tumor is superficial.

T1b: The tumor is deep.

T2: The size of the tumor is larger than 5 cm.

T2a: The tumor is superficial.

T2b: The tumor is deep.

Node (N)

The "N" in the TNM staging system stands for lymph nodes, the tiny, bean-shaped organs that help fight infection. Lymph nodes near where the cancer started are called regional lymph nodes. Lymph nodes in other parts of the body are called distant lymph nodes. Soft-tissue sarcoma usually does not spread to the lymph nodes.

NX: The regional lymph nodes cannot be evaluated.

N0 (N plus zero): The cancer has not spread to the regional lymph nodes.

N1: The cancer has spread to the regional lymph nodes.

Metastasis (M)

The "M" in the TNM system indicates whether the cancer has spread to other parts of the body, called distant metastasis.

M0 (M plus zero): The cancer has not metastasized.

M1: There is metastasis to another part of the body.

Grade (G)

Doctors also describe this type of cancer by its grade (G), which describes how much cancer cells look like healthy cells when viewed under a microscope. The doctor compares the cancerous tissue with healthy tissue. Healthy tissue usually contains many different types of cells grouped together. If the cancer looks similar to healthy tissue and contains different cell groupings, it is called differentiated or a low-grade tumor. If the cancerous tissue looks very different from healthy tissue, it is called poorly differentiated or a high-grade tumor. The cancer’s grade may help the doctor predict how quickly the cancer will spread. In general, the lower the tumor’s grade, the better the prognosis.

There are 4 grades for sarcoma: GX (the grade cannot be evaluated), G1, G2, and G3. The grades are determined based on the factors below:

  • How different the cancer cells are from normal tissue cells

  • How many tumor cells are dividing

  • How much of the tumor has cells that are dying

The lower the combined score for these 3 factors, the lower the grade. A lower grade means that the tumor is less aggressive and that a patient’s prognosis is better. This is the recommended grading system, but other systems may also be used. For instance, some doctors grade sarcomas as either “low grade” or “high grade,” particularly if the tumor has been treated before surgery.

Cancer stage grouping

Doctors assign the stage of the cancer by combining the T, N, M, and G classifications. For sarcoma, stages I and II are described in smaller groups according to the tumor's depth.

Stage IA: The tumor is 5 cm or less in size, and it is either superficial or deep. It has not spread to lymph nodes or to other parts of the body (T1a or T1b, N0, M0, GX or G1).

Stage IB: The tumor is more than 5 cm in size, and it is either superficial or deep. It has not spread to lymph nodes or to other parts of the body (T2a or T2b, N0, M0, GX or G1).

Stage IIA: The tumor is 5 cm or less in size, and it is either superficial or deep. It has not spread to lymph nodes or to other parts of the body. The grade is higher than the grade for stage IA (T1a or T1b, N0, M0, G2 or G3).

Stage IIB: The tumor is more than 5 cm in size, and it is either superficial or deep. It has not spread to lymph nodes or to other parts of the body. The grade is higher than the grade for stage IB (T2a or T2b, N0, M0, G2).

Stage III: This stage can be described by either of the following:

  • The tumor is more than 5 cm in size, and it is either superficial or deep. It has not spread to lymph nodes or to other parts of the body. The grade is higher than the grade for stage IIB (T2a or T2b, N0, M0, G3).

  • The tumor is any size, either superficial or deep, or any grade. It has spread to the regional lymph nodes but not to other parts of the body (any T, N1, M0, any G).

Stage IV: The tumor is any size, either superficial or deep, any grade, and may or may not have spread to the regional lymph nodes. It has spread to other parts of the body (any T, any N, M1, and any G).

This staging system applies to most types of soft-tissue sarcoma except Kaposi sarcoma; GIST; infantile fibrosarcoma; sarcomas that begin in the central nervous system, which includes the brain or the lining around the brain and spinal cord; and sarcomas that begin in an organ or a hollow organ, such as the bowel or urinary tract.

Recurrent: Recurrent cancer is cancer that comes back after treatment. If the cancer does return, there will be another round of tests to learn about the extent of the recurrence. These tests and scans are often similar to those done at the time of the original diagnosis.

Used with permission of the American Joint Committee on Cancer (AJCC), Chicago, Illinois. The original source for this material is the AJCC Cancer Staging Manual, Seventh Edition, published by Springer-Verlag New York, www.cancerstaging.net.

Information about the cancer’s stage will help the doctor recommend a specific treatment plan. The next section in this guide is Treatment Options. Or, use the menu to choose another section to continue reading this guide.