Staging and grading of stomach cancer

The stage and grade of the stomach cancer describes the cancer, whether it has spread and how quickly it may develop.

Staging of stomach cancer

The stage of the cancer describes the position of the cancer and whether it has spread from where it started. Knowing the stage helps doctors decide on the best treatment for you.

Your cancer doctor can use the results of your tests to try to identify the stage of the cancer. They will do this before surgery, or if you cannot have surgery. But they may not know the exact stage of the cancer until it has been removed with surgery.

Your healthcare team may describe the cancer you have using the:

  • TNM staging system
  • number staging system.

The TNM staging system is the one most commonly used for stomach cancer.

TNM staging system

TNM stands for tumour, nodes and metastasis. It can help to look at the information about the stomach wall when you read this to understand the staging.

  • T describes how far the tumour has grown into the stomach wall.
  • N describes whether the cancer has spread to the lymph nodes.
  • M describes whether the cancer has spread to other parts of the body (metastases).

Tumour

  • T1 means the tumour has grown into the inner wall (mucosa or submucosa) of the stomach:
    • T1a – the tumour has grown into the mucosa.
    • T1b – the tumour has grown into the submucosa.
  • T2 means the tumour has grown into the muscle layer (muscularis) of the stomach.
  • T3 means the tumour has grown into the outer lining of the stomach.
  • T4 means the tumour has grown through the outer lining (serosa) of the stomach, or into nearby structures:
    • T4a – the tumour has grown through the outer lining (serosa) of the stomach.
    • T4b – the tumour has grown into nearby structures, such as the liver or pancreas.

Nodes

  • N0 means there are no cancer cells in any nearby lymph nodes.
  • N1 means there are cancer cells in 1 to 2 nearby lymph nodes.
  • N2 means there are cancer cells in 3 to 6 nearby lymph nodes.
  • N3 means there are cancer cells in 7 or more nearby lymph nodes:
    • N3a means there are cancer cells in 7 to 15 nearby lymph nodes.
    • N3b means there are cancer cells in 16 or more nearby lymph nodes.

Metastases

  • M0 means the cancer has not spread to other parts of the body.
  • M1 means the cancer has spread to other parts of the body, such as the lungs or liver.

Number staging system

Another system used to describe the stage of the cancer is the number staging system. It uses the numbers 1 to 4.

Your cancer doctor can explain number staging to you and how the number stage relates to the TNM stage. There are different number staging systems, depending on if the cancer is staged before or after surgery.

Grading of stomach cancer

Grading is about how the cancer cells look under the microscope compared with normal cells. The grade of the cancer gives the doctors an idea of how quickly it may develop.

  • Grade 1 (also called low grade or well differentiated) means the cancer cells look similar to normal cells, usually grow slowly and are less likely to spread.
  • Grade 2 (moderate or intermediate grade) means the cancer cells look more abnormal and grow slightly faster.
  • Grade 3 (high grade or poorly differentiated) means the cancer cells look very different from normal cells, may grow more quickly and are more likely to spread.

We understand that waiting to know the stage and grade of your cancer can be a worrying time. We are here if you need someone to talk to. You can:

Date reviewed

Reviewed: 31 December 2019
|
Next review: 30 June 2022

This content is currently being reviewed. New information will be coming soon.

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