Page last updated: April 2025
The information on this webpage was adapted from Understanding Bowel Cancer - A guide for people with cancer, their families and friends (2025 edition). This webpage was last updated in April 2025.
Expert content reviewers:
This information was developed based on Australian and international clinical practice guidelines, and with the help of a range of health professionals and people affected by bowel cancer:
- Prof Alexander Heriot, Colorectal Surgeon and Director Cancer Surgery, Peter MacCallum Cancer Centre, Director, Lower GI Tumour Stream, Victorian Comprehensive Cancer Centre, VIC
- Dr Cameron Bell, Gastroenterologist, Royal North Shore Hospital, NSW
- Graham Borgas, Consumer
- Prof Michael Bourke, Director of Gastrointestinal Endoscopy, Westmead Hospital, The University of Sydney, NSW
- Laura Carman, 13 11 20 Consultant, Cancer Council Victoria, VIC
- Amanda Connolly, Specialist Bowel Care Nurse, Icon Cancer Centre Windsor Gardens, SA
- A/Prof Melissa Eastgate, Operations Director, Cancer Care Services, Royal Brisbane and Women’s Hospital, QLD
- Anne Marie Lyons, Stomal Therapy Nurse, Concord Repatriation General Hospital and NSW Stoma Ltd, NSW
- Lisa Nicholson, Manager Bowel Care Services, Bowel Cancer Australia, NSW
- Stefanie Simnadis, Clinical Dietitian, St John of God Subiaco Hospital, WA
- Rafi Sharif, Consumer
- Dr Kirsten van Gysen, Radiation Oncologist, The Nepean Cancer and Wellness Centre, NSW
- Sarah Williams, Clinical Nurse Consultant, Lower GI, Peter MacCallum Cancer Centre, VIC
When bowel cancer has spread to other parts of the body such as the liver, lung or lining of the abdomen and pelvis (omentum and peritoneum), it is called advanced or metastatic (stage 4) bowel cancer.
To control the cancer, slow its growth and manage symptoms such as pain, a combination of different treatments may be recommended. These may include chemotherapy, targeted therapy, immunotherapy, radiation therapy and surgery.
For some people, the best option may be to join a clinical trial.
Your guide to best cancer care
A lot can happen in a hurry when you’re diagnosed with cancer.
The guide to best cancer care for bowel cancer can help you make sense of what should happen. It will help you with what questions to ask your health professionals to make sure you receive the best care at every step.
Read the guide
Drug therapies
Advanced bowel cancer is commonly treated with drugs that reach cancer cells throughout the body. This is called systemic treatment, and includes chemotherapy, targeted therapy and immunotherapy.
The drugs used for bowel cancer are rapidly changing as clinical trials find newer drugs. Your medical oncologist will discuss which combination of drugs is best for your situation. You may also be able to get other drugs through a clinical trial.
Scans and blood tests will be used to monitor your response to systemic treatments. If results show that the cancer is shrinking or is under control, you’ll continue to have chemotherapy or targeted therapy or both.
If the cancer is growing, that treatment will stop and your doctor will discuss other treatments.
Targeted therapy
This is a type of drug treatment that attacks specific features of cancer cells to stop the cancer growing and spreading. Monoclonal antibodies are the main type of targeted therapy drug used in Australia for advanced bowel cancer.
There are a range of different targeted therapy drugs. These drugs will only work for bowel cancers with particular gene changes (mutations).
Your medical oncologist will usually do tests on the biopsy sample (or may do blood tests) to see which targeted therapy is likely to work for you.
Some targeted therapy drugs are given as tablets, while others are given as a drip into a vein in hospital. They may sometimes be given at the same time as chemotherapy, or given after you have stopped chemotherapy treatment.
Side effects
The side effects of targeted therapy vary depending on which ones are used. Some of the more common side effects may include: tiredness, skin problems, diarrhoea, joint pain, skin problems and sore eyes.
Learn more about targeted therapy
Immunotherapy
Immunotherapy is a type of drug therapy treatment that uses the body’s own immune system to fight cancer.
Checkpoint inhibitors are the main type of immunotherapy drug used for the small number of advanced bowel cancers that have a fault in the mismatch repair (MMR) gene.
The drug pembrolizumab is given directly into a vein through a drip (infusion) and the treatment is repeated every 3 or 6 weeks. How many infusions you receive will depend on how you respond to the drug.
Side effects
Checkpoint inhibitor immunotherapy acts on the immune system, so it can sometimes cause the immune system to attack healthy cells in any part of the body.
This can lead to a variety of side effects such as rash, itchy skin, diarrhoea, breathing problems, inflammation of the liver, hormone changes and temporary arthritis. Your doctor will discuss possible side effects with you.
Learn more about immunotherapy
Radiation therapy
Radiation therapy can be used as a palliative treatment for both advanced colon and advanced rectal cancer. It can be used to control the growth of the tumour and relieve symptoms such as bleeding.
If the cancer has spread to the bone or formed a mass in the pelvis, radiation therapy can reduce pain. If the tumour has spread to the liver, you may be offered a specialised type of radiation therapy.
Options may include selective internal radiation therapy (SIRT, also called radioembolisation) or stereotactic body radiation therapy (SBRT).
Learn more
Surgery
Some people are able to have surgery to remove bowel cancer that has spread. Generally, surgery is not recommended if you are unwell or the cancer has spread to many places in the body.
- If the cancer has spread, surgery may remove parts of the bowel along with all or part of other affected organs. This is called an enbloc resection and is usually for locally advanced bowel cancer. If the liver, lungs or other organs are affected, a separate surgery (called metasectomy) may remove some or all of the cancer in that organ.
- If the cancer has spread to the lining of the abdomen (peritoneum), some people have surgery to try to remove all of the cancer – however, this can only be done when there is limited cancer and spread. This is known as a peritonectomy or cytoreductive surgery. Sometimes, a heated chemotherapy solution is put into the abdomen for 60–90 minutes during a peritonectomy. This is called hyperthermic intraperitoneal chemotherapy (HIPEC).
Learn more about surgery
Thermal ablation
If the cancer has spread to only a small number of places in a single area, such as the liver or lungs, your doctor may recommend thermal ablation. This may use heat to destroy the tumour.
The heat may come from radio waves (radio frequency ablation) or microwaves (microwave ablation). It is best performed in a specialised centre.
Cryoablation is a similar process that may sometimes be offered, and uses cold or freezing instead of heat.
Palliative treatment
This is treatment that aims to slow the spread of cancer and relieve symptoms, such as pain, without trying to cure the disease.
Treatments given palliatively for advanced bowel cancer may include surgery, chemotherapy, radiation therapy or targeted therapy.
Learn more