Bowel cancer is any cancer that affects the bowel, otherwise known as the intestines, or by the medical term 'colon'. Bowel cancer is also referred to as 'colorectal cancer' and also refers to cancer of the rectum, which is the lower section of the colon closest to the anus.
Recent statistics (2015) indicate that around 17,000 are diagnosed with bowel cancer in Australia every year, which makes it the second most common cancer in Australia. It is slightly more common in men than in women and people aged over 50 are at greater risk than those under this age.
The most common form of cancer starts as a malignant (ie cancerous) tumour in the wall of the large colon, or where a polyp has become cancerous (even though most polyps are benign, that is they are not cancerous).
If bowel cancer is not diagnosed soon enough, it can spread deeper into the lining of the colon and then to other parts of the body, such as the lymph nodes, and often the lungs and the liver.
What causes bowel cancer?
There is still some uncertainty about what causes bowel cancer, however medical science has discovered some risk factors for developing this cancer. These are...
- Being over 50 years old. Unfortunately you can't do much about this, but bowel cancer is more common in those over 50 and risk increases with age from there, with 1 in 10 men and 1 in 15 women over 85 contracting bowel cancer
- Other bowel problems - those people who have had inflammation of the bowel (ulcerative colitis) for many years (over 8) are more at risk of bowel cancer
- Genetic predisposition - a family history of bowel cancer and/or the presence of two rare genetic disorders - Lynch Syndrome or Familial Adenomatous Polyposis
- Lifestyle factors - many factors may contribute to a greater risk of bowel cancer. However please note these are associations and includs drinking alcohol (more than 14 standard drinks per week), smoking, being overweight, little or no fruit or vegetables in the diet (ie low fibre intake), a high intake of red meat and/or processed meat, little or no physical activity or exercise
What are the symptoms of bowel cancer?
There are often no symptoms at all when bowel cancer is at an early stage. The following symptoms may indicate bowel cancer and you should have any of these checked out by your doctor as soon as you notice them...
- Blood (or mucus) in your faeces
- Any unexplained change in toilet habits eg diarrhoea or constipation
- Abdominal pain
- Constant tiredness
- Paleness of complexion
- Unexplained weight loss
How is bowel cancer diagnosed?
Various tests will indicate whether someone is suffering from bowel cancer. These may include
- FOBT - this stands for Faecal OccultBlood Test (see more details on this test here) – this test should not be used if you are having symptoms. Only for patients who are asymptomatic and used only as a screening tool.
- Rectal examination
- Colonoscopy – see this section for more information on colonscopy
- various body scans (ultrasound/PET/CT/MR)
How is bowel cancer treated?
This depends entirely on the location of the cancer, the size of the tumour, how aggressive the tumour is and whether the cancer has spread to other parts of the body. Generally treatment is by surgery and/or other treatments such as radiation therapy and chemotherapy. We will be able to advise you more accurately as to treatment options based on your diagnosis.