Grading and staging of soft tissue sarcomas

Your doctors will need to find out the grade and stage of the cancer. This will help them decide on the most appropriate treatment for you.

The grade of a cancer gives an idea of how quickly it might grow. Doctors look at the cancer cells under a microscope and see how they compare with normal cells. The grade helps your doctor decide if you need further treatment after surgery.

Low-grade cancer cells look similar to normal cells and are less likely to spread. High-grade cancer cells look very different from normal cells and may grow quickly.

Grading of soft tissue sarcomas can sometimes be difficult, especially for the less common types. Your doctor will be able to talk to you in more detail about grading.

Staging is used by your doctor to describe the size of the cancer and where it has spread beyond the original area in the body. Two of the most commonly used systems for staging soft tissue sarcomas are a number staging system and the TNM staging system.

Grading and staging

The information from your biopsy, scans and other tests will tell your doctors more about the grade and stage of your cancer. This information will be used by a team of doctors and nurses known as the multidisciplinary team or MDT. Your MDT will decide on the most appropriate treatment for you.

Doctors examine the cancer cells under a microscope and compare them with normal cells.

This helps them grade the cancer. The grade helps your doctor to decide if you need further treatment after surgery.

  • Grade 1 or low-grade or well differentiated – The cancer cells look similar to normal cells and usually grow slowly and are less likely to spread.
  • Grade 2 or moderate or intermediate-grade – The cancer cells look more abnormal and are slightly faster growing.
  • Grade 3 or high-grade or poorly differentiated – The cancer cells look very different from normal cells and may grow more quickly.

Grading of soft tissue sarcomas can sometimes be difficult, especially for the less common types. Your doctor will be able to talk to you in more detail about grading.


Staging

The stage of a cancer describes its size and whether it has spread beyond its original area in the body.

Several different staging systems may be used. Two of the most commonly used systems for staging soft tissue sarcomas are a number staging system and the TNM staging system.

Number staging

In this system, there are four main stages from 1–4, which may be further subdivided:

Stage 1A

The cancer is small (5cm or less) and either low-grade or the grade isn’t known. It can either be close to the surface of the body (superficial) or deep within the body.

Stage 1B

The cancer is larger than 5cm and either low-grade or the grade isn’t known. It can be either superficial or deep within the body.

Stage 1 soft tissue sarcomas have not spread to lymph nodes or other parts of the body.

Stage 2A

The cancer is small (5cm or less) and either moderate- grade or high-grade. It can either be superficial or deep within the body.

Stage 2B

The cancer is larger than 5cm and moderate-grade. It can be either superficial or deep within the body.

Stage 2 soft tissue sarcomas have not spread to lymph nodes or other parts of the body.

Stage 3

The cancer is bigger than 5cm and high-grade. It can be either superficial or deep within the body, and has not begun to spread. OR The cancer is of any size, superficial or deep and of any grade, but it has spread to at least one lymph node, but not to other parts of the body.

Stage 4

The cancer can be any size, superficial or deep, and of any grade. It may or may not have spread to lymph nodes, but it has spread to another part of the body such as the lungs, liver, bones or soft tissues. This is known as secondary or metastatic cancer.


TNM staging

TNM staging looks at the size of the tumour, whether the cancer has spread to the lymph nodes and whether it has spread to other parts of the body.

T stands for Tumour

Doctors put a number next to the ‘T’ to describe the size and spread of the cancer.

There are two T stages for soft tissue sarcomas and each is divided into ‘a’ and ‘b’:

T1 – The tumour is 5cm or less in size.

  • T1a – The tumour is near the surface of the body (superficial).
  • T1b – The tumour is deep in the body.

T2 – The tumour is more than 5cm in size.

  • T2a – The tumour is superficial.
  • T2b – The tumour is deep in the body.

N stands for Nodes

This describes whether there are any lymph nodes near the tumour that have cancer in them. The ‘N’ may have an ‘X’ or a number written next to it, which gives extra information about the nodes that were examined:

NX – The lymph nodes were not examined.

N0 – The lymph nodes were examined but no cancer was found.

N1 – There are cancer cells in at least one lymph node.

If cancer cells have spread to the lymph nodes, the nodes are said to be positive. It’s uncommon for soft tissue sarcomas to spread to the lymph nodes. Positive nodes (N1) are classified as a stage 3 sarcoma (see number staging).

M stands for Metastasis

Metastasis means that the cancer has spread to other parts of the body such as the liver or lungs. This is called secondary or metastatic cancer. The ‘M’ may have a number written next to it, which gives extra information about whether the cancer has spread or not:

M0 – The cancer has not spread to other parts of the body.

M1 – The cancer has spread to another part of the body.

Our cancer support specialists on 0808 808 00 00 can tell you more about TNM staging. It’s also important to talk to your doctor for detailed information about your situation.

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