Stages of lung NETs

The stage of a lung neuroendocrine tumour (NET) tells you its size and whether it has spread. There are different ways to stage lung NETs.

How doctors find out the stage

You have tests and scans to diagnose a lung NET. These give some information about the stage of the cancer. Sometimes it’s not possible to be certain about the stage of a lung NET until after surgery.

Knowing the stage can help your doctor decide which treatment you need.

Types of staging

Doctors use the number system or the TNM system to stage lung NETs. There is also a simplified staging system for a type of lung NET called small cell lung cancer (SCLC).

Doctors use the same number and TNM staging systems for lung NETs as for other types of lung cancer.

TNM staging

The TNM staging system is the most common way for doctors to stage lung NETs. TNM stands for tumour, node and metastasis:

  • T describes the size of the tumour
  • N describes whether there are cancer cells in the lymph nodes
  • M describes whether the cancer has spread to a different part of the body

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Number staging

Your doctor might tell you the number stage of your lung NET. This system divides NETs into 4 main groups, depending on the size of the tumour and whether it has spread.

Stage 1 is the earliest stage. It means that the tumour is small and hasn’t spread to the lymph nodes or other parts of the body. Stage 4 is the most advanced stage.

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Limited and extensive stage

Doctors often use a simple system to stage small cell lung cancer (SCLC). This describes your cancer as limited disease or extensive disease.

Limited disease is when the cancer is in a single area that can be treated with radiotherapy. Extensive disease means that the cancer has spread beyond a single area, or there are cancer cells in the fluid around the lung (a malignant pleural effusion).

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The stage of the lung NET helps your doctor decide which treatment you need. Treatment also depends on:

  • the type of lung NET (the type of cells the tumour started in)
  • where the tumour is
  • other health conditions you may have
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  • The information on this page is based on literature searches and specialist checking. We used many references and there are too many to list here. Please contact with details of the particular issue you are interested in if you need additional references for this information.

Last reviewed: 
25 Mar 2021
Next review due: 
25 Mar 2024

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