Colon, Bowel & Colorectal Cancer
Colon cancer – also known as bowel or colorectal cancer – is the 2nd most common cancer in Australia. It affects over 12,500 Australians each year.
Australia has one of the highest rates of colon cancer in the world, with an estimated 1 in 13 Australians facing a diagnosis at some time in their lives. People over the age of 50 are most affected, but it can also develop in younger people.
Although it’s undoubtedly a serious disease, colon cancer is often curable if caught early.
How does colon cancer develop?
Colon cancer can affect any part of the large bowel (colon), and sometimes the rectum. It develops in the lining of the bowel, usually beginning as little cherry-like growths called polyps. Most polyps are benign (non-cancerous), however some of these can develop into invasive cancer.
This development can happen over years if untreated polyps spread deeper into the wall of the bowel. In later stages, colon cancer can spread to lymph nodes, the liver and/or the lungs.
Types of colon cancer
Over 95% of colon cancers are classified as adenocarcinomas, meaning they began in gland cells within the bowel lining. Other rarer types include squamous cell cancers, carcinoid tumours, sarcomas, and lymphomas.
Colon cancer symptoms
Signs and symptoms of colon cancer may include:
- A change in your regular bowel habits lasting longer than 4 weeks
- Blood or mucus in the faeces or on toilet paper
- Persistent cramps, gas or pain in your abdomen
- Feeling your bowels don’t empty completely after going to the toilet
- Unexplained weakness, fatigue, and/or weight loss
- A lump in your anus or rectum
Colon cancer often doesn’t present with symptoms during its early stages. When symptoms do appear, they may vary depending on the cancer’s size and location within the large intestine.
Colon cancer risk factors
Although the exact cause of colon cancer is not clearly understood, there are some risk factors that are known to increase a person’s risk of developing the disease.
- Ageing – bowel cancer most commonly affects people over 50
- Genetics – inheriting familial adenomatous polyposis (FAP) or Lynch syndrome (formerly known as non-polyposis colorectal cancer (HNPCC)
- Family history – especially first-degree relatives who have had bowel cancer
- Ulcerative colitis – an inflamed lining of the colon for 8-10 years
There is also growing evidence that diet and lifestyle play an important role for developing colon cancer.
Diets high in red and processed meat, drinking more than two standard alcoholic drinks per day, smoking, and obesity may all increase your risk of developing colon cancer.
Colon cancer screening
Screening is used to detect problems in the bowel that may indicate colon cancer. The current standard in Australia is a non-invasive test (the FIT – faecal immunochemical blood test) that checks for blood in the stool. It involves putting a small stool sample on a special card and sending it to a pathology laboratory via a postage paid envelope.
All Australians aged 50 to 75 are offered this test every 2 years for free via the National Bowel Screening Program. People with an increased risk of colon cancer, such as those with a family history of the disease, are advised to get screened sooner and more regularly. This can mean a FIT test every year, and colonoscopy every five years.
A positive result does not necessarily mean colon cancer is present; rather it indicates there is blood in the stool. Further investigation happens via a colonoscopy within 30 days of the positive result.
Colon cancer diagnosis
There are several tests that may be used to diagnose colon cancer. These include:
- Rectal examination – to feel for abnormalities in the rectum.
- Colonoscopy – to visually examine the length of the large bowel.
- CT scan – to produce 3D images of the bowel.
- Blood tests – to detect a carcinoembryonic antigen (CEA).
- PET scan – using a small amount of radioactive glucose to highlight cancerous cells during imaging.
- Ultrasound – using soundwaves that echo against dense tissue such as a tumour.
Your oncologist may order one or more of these tests depending on your individual circumstances.
Colon cancer stages
In Australia, colon cancer is staged as follows:
- Stage I – the cancer is confined to the wall of the bowel
- Stage II – the cancer has spread deeper in to the muscle of the bowel wall
- StageIII – the cancer is found in lymph nodes near the bowel
- Stage IV – the cancer has spread to organs beyond the bowel
Colon cancer treatment
Treatment for colon cancer depends on the size and type of the cancer, its stage, your family history, and your overall health. Your oncologist will work closely with you to develop a treatment plan suited to your situation that promotes a positive outcome.
Treatment for cancer may include surgery, radiotherapy, cryosurgery, chemotherapy, radiation therapy, targeted therapies, or a combination of these. For some patients, clinical trials may be considered as a treatment choice.
What to expect at your first appointment
Cancer diagnosis and subsequent treatment can be a frightening time. That’s why at Hunter Valley Oncology, we aim to give you the guidance and care you need at every stage of your cancer journey.
After your GP has referred you to our Maitland or Newcastle cancer clinic, our first steps will be helping you understand the information you’re receiving. We are here to answer your questions, address your concerns, and give you a solid understanding of your diagnosis and treatment options.
We begin consultations with a medical history review, so please bring a list of your current medications with you. We’ll also review your family’s medical history, and assess your current level of health and fitness.
If we need more information from you before a full discussion about your treatment options can occur, your oncologist will advise a second appointment. This enables them to undertake a thorough investigation into your diagnosis, prognosis and suggested treatment options.
Once you and your oncologist agree upon a treatment plan, treatment will commence at our Maitland or Newcastle cancer clinic. Dr Paterson treats patients at two hospitals in the Hunter and Newcastle region – Newcastle Private Hospital and Lake Macquarie Private Hospital.