Colorectal Cancer

What are the treatment options for colorectal cancer?

The primary treatment options for colorectal cancer include surgery, radiation therapy, chemotherapy, targeted therapy and immunotherapy. The type of treatment you receive will depend on a number of different considerations, such as if you have colon cancer or rectal cancer, the cancer’s stage, your overall health and your treatment preferences. This page aims to give you a comprehensive overview of how colorectal cancer treatment works.

Colonoscopy for colorectal cancer

A colonoscopy can both diagnose and treat colorectal cancer. The procedure involves inserting a colonoscope (a tube with a camera attached) into the anus, through to the rectum and colon.

Colonoscopies are used for many different purposes.

Local excisions are commonly used for early-stage rectal cancer. Methods include:

• Transanal excision (TAE) – This procedure involves the removal of cancer from the lower rectal wall, including any surrounding rectal tissue. This is done through making minor incisions into the rectum.

• Transanal endoscopic microsurgery (TEMS) – Specialised equipment is inserted into the anus to remove cancers in the upper rectum which may not be accessible through a transanal excision.

• Transanal minimally invasive surgery (TAMIS) – Specialised equipment is inserted into the anus to remove the rectal cancer with minimal invasion.

Surgery for colorectal cancer

Surgery for colorectal cancer is performed to remove cancerous tissue and relieve symptoms when the cancer has advanced. Most people with colorectal cancer will receive surgery as their primary form of treatment. The two approaches for surgery, performed under general anaesthesia, include:

• Open colectomy – where a long incision is made through the skin and abdominal wall to access your colon or rectum cancer. Typically, half of the colon on the side of your tumour is removed e.g. left sided colon cancers have a left colectomy

• Keyhole (laparoscopic) colectomy – a minimally invasive procedure that uses three to four small incisions to access the colon or rectum cancer. Keyhole procedures result in less postoperative pain and complications, shorter hospital stay, and faster recovery compared to open colectomy.

Even though they both fall under colorectal cancer, colon cancer and rectal cancer are unique and are treated differently.

Colectomy

A colectomy (also known as a colorectal resection) is a major surgery that involves the removal of all or part of the colon and/or rectum, including nearby lymph nodes.

Depending on the type of colectomy you receive, your surgeon may make a cut between both ends of your cancer and reconnect them back together (called an anastomosis). Sometimes, the ends of the bowel may not be able to be joined together. In these cases, a new opening will be made in your abdomen. An opening in the large bowel is known as a colostomy, whereas an opening in the small bowel is referred to as an ileostomy. The opening itself is called a stoma.

Stomas divert faecal waste out of the body. This waste is collected through a colostomy or ileostomy bag that is fixed around the stoma. A stoma can be temporary or permanent.

Radiotherapy for colorectal cancer

Radiation is a common treatment option for rectal cancer but is not generally used for colon cancer. It is typically delivered over the pelvic area in combination with chemotherapy. Types of radiotherapy commonly used for people with colorectal cancer include:

• External beam radiation therapy (EBRT)

• Brachytherapy

Chemotherapy for colorectal cancer

Chemotherapy uses a range of drugs to destroy and slow the growth of colorectal cancer. These drugs may be delivered at any stage of your colorectal cancer treatment.

Learn more about chemotherapy and how it is delivered.

Chemotherapy for colorectal cancer is delivered in multiple sessions called cycles. This means you will have one to three weeks of rest between receiving an injection or infusion. Your care team will walk you through how many cycles you may need for your course of treatment, with most people completing chemotherapy in a period of four to six months.

Targeted therapies for colorectal cancer

Targeted therapies use specialised drugs to destroy specific proteins or genes in colorectal cancer cells.

Targeted therapies are only effective for certain colon and rectal cancers, and are generally used to treat advanced colorectal cancers. Your care team will examine the make-up of your cancer cells to determine if targeted therapies are suitable for you.

Immunotherapy for colorectal cancer

Immunotherapy trains the immune system to recognise and fight colorectal cancer cells that are hiding behind your body’s natural defences. It is commonly used when your colorectal cancer has come back after initial treatment or has spread to other areas in the body.

Treatment by stage of colorectal cancer

When you are diagnosed with colorectal cancer, your oncologist will develop your treatment plan as part of a multidisciplinary team based on the stage of your cancer and whether you have colon cancer or rectal cancer.