Stage 3

Stage 3 anal cancer can be different sizes. It's spread to nearby tissue or lymph nodes. It hasn't spread to distant body parts. 

Stage 3 anal cancer is divided into 3 groups - 3A, 3B and 3C. 

Stage 3A

Stage 3A means the cancer is no bigger than 5cm.  

It has spread to nearby lymph nodes in the rectum, pelvis or the groin. But it hasn't spread to other parts of the body.

Stage 3B

Stage 3B means the cancer is any size and is growing into the surrounding organs, such as the bladder, the tube that carries urine from the bladder out of your body (the urethra) or the vagina.

The cancer hasn't spread to the lymph nodes or other parts of the body.  

Stage 3C

Stage 3C cancer has spread to nearby lymph nodes but not to other parts of the body. It also means one of the following:

  • the cancer is larger than 5cm
  • the cancer is any size and has grown into surrounding organs, such as the urethra, vagina or bladder

TNM staging

Doctors also use another staging system for anal cancer called the TNM staging system. It stands for tumour, node and metastasis: 

T describes the size of the tumour.

N describes whether the cancer has spread to the lymph nodes.

M describes whether the cancer has spread to a different part of the body.

In the TNM staging system, stage 3A anal cancer is the same as:

  • T1, N1, M0  
  • T2, N1, M0

In the TNM staging system, stage 3B anal cancer is the same as:

  • T4, N0, M0

In the TNM staging system, stage 3C anal cancer is the same as:

  • T3, N1, M0
  • T4, N1, M0. 


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

  • your type of cancer (the type of cells the cancer started in)
  • where the cancer is
  • other health conditions


The main treatment for stage 3 anal cancer is chemoradiotherapy. This means you have chemotherapy and radiotherapy together.

You might have surgery if the cancer hasn't gone completely after chemoradiotherapy or if it comes back. 

Other stages

Last reviewed: 
26 Apr 2019
  • AJCC Cancer Staging Manual (8th edition)
    M Amin and others 
    Springer, 2017.

  • Anal cancer: ESMO-ESSO-ESTRO Clinical Practice Guidelines for diagnosis, treatment and follow-up
    R. Glynne-Jones and others
    Annals of Oncology 2014. Volume 25, Pages iii10-iii20