Stage 3

The stage of a cancer tells you how big it is and how far it has spread. It helps your doctor decide which treatment you need.

Stage 3 is part of the number staging system. It generally means that cancer cells have spread to the lymph nodes close to where the melanoma started (the primary tumour). Or it has spread to an area between the primary tumour and the nearby lymph nodes.

This area is further divided into satellite or in-transit metastases. Satellite metastases are cancer cells that have spread very close to the primary tumour (within 2 cm). In-transit metastases are cancer cells that have spread further than 2 cm but before the nearest lymph node.  

In some cases, the primary tumour can’t be found but there are melanoma cells in the lymph nodes or nearby area.

Diagram showing a lymph node

Stage 3 melanoma is divided into A, B, C and D depending on where the cancer has spread to, such as if there are only satellite or in-transit metastases or if there is melanoma in one or several lymph nodes.

Your doctor or specialist nurse can tell your more about what your exact stage of melanoma means. 

Call Cancer Research UK’s information nurses on freephone 0808 800 4040 from 9am to 5pm, Monday to Friday, for more information about staging for melanoma.

TNM stages

Doctors also use another staging system for melanoma called the TNM staging system. It stands for Tumour, Node, Metastasis.

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


The stage of your cancer helps your doctor to decide what treatment you need. Treatment also depends on:

  • where the melanoma is
  • your general health and level of fitness

Your doctor may send a sample of the melanoma for genetic testing. This is to look for a change in a gene called BRAF. This genetic change can make melanoma cells grow.

If you have changes in the BRAF gene, doctors describe your melanoma as BRAF positive. If you don’t have changes, then your melanoma is BRAF negative. Knowing this helps your doctor make decisions about whether you need targeted cancer drugs or immunotherapy.

Melanoma in the area between the primary melanoma and the nearby lymph nodes (satellite or in-transit metastases)

You usually have surgery to remove satellite or in-transit metastases. If you’re not able to have surgery you might have one of the following:

  • laser surgery using a carbon dioxide laser
  • injecting treatment directly into the melanoma (intralesional therapy), for example talimogene laherparepvec (T-VEC)
  • chemotherapy combined with an electric current (electrochemotherapy)
  • chemotherapy directly into the leg or arm where the melanoma is (known as isolated limb infusion or isolated limb perfusion)
  • targeted cancer drugs
  • immunotherapy
  • chemotherapy
  • take part in a clinical trial

Melanoma in the lymph nodes

If your lymph nodes feel normal but a sentinel lymph node biopsy shows that a small number of melanoma cells have spread there, you might have either:

  • regular ultrasound scans to check your lymph nodes
  • treatment with targeted cancer drugs or immunotherapy

You don’t usually have surgery to remove the rest of the lymph nodes in this situation, except in specific circumstances. Your doctor will talk to you about this.

Some people may decide to have ultrasound surveillance of their lymph nodes instead of having a sentinel lymph node biopsy. In this case, you usually have regular ultrasound scans over 5 years. You may need a biopsy if there is a concern that melanoma is in your lymph nodes. 

You usually do have surgery to remove the lymph nodes in the area if they are swollen or abnormal looking and a biopsy has confirmed that the melanoma has spread there. This operation is called a completion lymph node dissection.

More treatment after surgery 

Your doctor might offer you further treatment after surgery to remove the cancer. This is called adjuvant treatment. The aim is to reduce the risk of the cancer coming back.

You might have targeted cancer drugs or immunotherapy for a year.

Clinical trial

Your doctor might ask if you’d like to take part in a clinical trial. Doctors and researchers do trials to make existing treatments better and develop new treatments.

Other number stages

Last reviewed: 
21 May 2020
Next review due: 
21 May 2023
  • AJCC Cancer Staging Manual (8th edition)
    American Joint Committee on Cancer
    Springer, 2017

  • Melanoma assessment and management
    National Institute for Health and Care Excellence, July 2015

  • BMJ Best Practice Melanoma
    BMJ Publishing Group, June 2018

  • Cutaneous melanoma: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up
    R Drummer and others
    Annals of Oncology, 2015. Volume 26, Supplement 5, Pages v126 - v132

  • The Current Role of Sentinel Lymph Node Biopsy in the Management of Cutaneous Melanoma – a UK Consensus Statement based on a multi-disciplinary meeting held in Cambridge, UK on 17 May 2018
    Melanoma Focus, January 2019

  • 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.

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