Lower gastrointestinal cancer

Lower gastrointestinal cancer is also called colorectal, bowel or colon cancer

Cancer Education
2 min read

Lower gastrointestinal cancer happens in the large intestine of the digestive system. The digestive system relates to how we eat and process food. It has two intestines that travel from the stomach to the anus.

About the lower gastrointestinal system

The large intestine is about 1.5 metres long and is the lowest part of the digestive system. The two intestines are: 

  • Small intestine (or small bowel): where food comes from the stomach and is further broken down into vitamins and nutrients we need to live 
  • Large intestine (or large bowel): connected to the small intestine. This is where the food product passes to, from the small intestine. This food product moves into the colon. The body absorbs water from it. The food product waste then passes into the rectum, which is the last few inches of the colon. It then leaves the body via the anus as part of a bowel motion. 

Focusing on you 

We place you at the centre of our work. Your cancer specialist will find out where your cancer started. They will also find out how far it has progressed. Lower gastrointestinal cancers can happen in any area of the large intestine. Most usually they start in the lining or tissue (inside wall) of the large intestine. Most colon cancers start when small clumps of cells come together to form into a polyp. This is a small lump on a stalk/stem/tail growing from the tissue. Over time these polyps can become abnormal and grow into cancer. It can spread through the muscle, tissue, and wall of the bowel and into other nearby organs. 

Lower gastrointestinal cancer diseases 

Your needs come first. We offer expert care across several different Lower Gastrointestinal diseases including: colon cancer; rectal cancer; metastatic colorectal cancer; anal cancer; advanced pelvic cancer; appendix cancer; peritoneal cancer; and pseudomyxoma peritonei.


We understand how stressful and difficult cancer can be. 

Your team of experts are sensitive to your individual health and wellbeing needs – we are here to help.  

You will need a referral from your GP or medical practitioner to access this service. 

Find out more about Getting started at Peter Mac

Related links

Cancer Council

Colonoscopy for Aboriginal and Torres Strait Islander peoples – Fact sheet

Pages related to lower gastrointestinal cancer

Go back to the Gastrointestinal cancer page