Why BowelScan is Important

Colorectal cancer is the commonest internal cancer affecting both sexes in Australia and is second only to lung cancer as a cause of cancer related death. On average 1 in 19 Australian men and 1 in 27 Australian women will develop colorectal cancer by the age of 75 years. Colorectal cancer (CRC) is mostly seen in persons aged 40 years and over and from age 50 years its incidence rises sharply.

It is the only preventable cancer in men and one of two in women, the other being cervical cancer. Yet almost as many women die of bowel cancer as of breast cancer.

Australia and New Zealand have the highest incidence of bowel cancer in the world, and a poor diet of insufficient fibre and high in saturated fat, smoking and alcohol are contributing factors. A high fibre diet will not necessarily prevent bowel cancer, however annual testing and early detection will reduce deaths.

What is Colorectal Cancer?

Colorectal cancer is an uncontrolled, malignant (destructive) growth of the mucosal cells of the colon (large intestine) or the rectum. These cancer masses grow rapidly without regard to the usual control mechanisms of the body, invade local adjacent structures, may cause bowel obstruction or spread to distant parts of the body (metastases) where they may disrupt function of other organs such as the liver. Colorectal cancer frequently ulcerates and bleeds. Often microscopic bleeding is present long before the patient develops symptoms. This interval before any symptoms becomes evident is the period where screening tests for colorectal cancer are most indicated as it is the window of opportunity to effect the only known cure of the disease by surgically removing the cancer. Annual screening of persons at risk provides the best chance of detecting the intermittent bleeding from these early cancers or polyps.

What is a Polyp?

A polyp is a small often rounded mass of growing cells of the intestinal lining and is the earliest stage of colorectal cancer development. Cells making up the polyp are usually benign adenomas (non-malignant) but a small percentage may, over a period of time, become cancerous. Polyps, like cancers, may bleed. As with all cancers, colorectal cancer progresses in stages. In its earliest stages, colorectal cancer is one of the most curable cancers, with predictions of a 95% cancer for a five year survival in stage 1, as opposed to only a 3% survival rate in stage IV.

What are the Symptoms of Colorectal Cancer?

During the early stages of colorectal cancer development, when the tumour is either a small benign polyp or small cancer, there are usually no symptoms. Yet this early stage of the disease is where the best outcomes are achieved in population screening by programs such as Rotary’s BowelScan. The cancer begins almost always as a non-malignant projection from the bowel wall known as a polyp, or adenomatous polyp. The process of change from a polyp to a cancer is slow – taking up to ten years. Most, but not all, polyps and cancers bleed from time to time. Bleeding from polyps and early cancers may not be visible, but can be detected by a simple chemical test of bowel motions. Procedures that detect and remove polyps and early cancers can be expected to reduce deaths from cancer.

The obvious symptoms of possible bowel cancer are:

Visible blood in the toilet bowl following a bowel movement; blood mixed with mucus
Rectal bleeding
Persistent change in bowel habits, e.g. constipation or diarrhoea
Persistent cramping or abdominal pain
Unexplained loss of weight, general weakness, tiredness and breathlessness
If any of these symptoms are evident, people should consult their doctor without delay.

More Facts about Bowel Cancer

The incidence of bowel cancer has not fallen over the past 20 years.
The lifetime risk of developing cancer in the bowel is 1 in 24.
The chance of contracting bowel cancer increases progressively from the age of 40.
It is predicted that there will be 11,000 cases of bowel cancer diagnosed in Australia annually, around 5,500 deaths now occur every year, double the National road toll.
You increase the risk of bowel cancer 2 to 3 times if you have one or more close relatives who have had colorectal cancer or polyps.
There may be no obvious symptoms of bowel cancer until the cancer has reached an advanced stage.
Once symptoms of bowel cancer have developed, the chance of long term survival is roughly halved.
A personal history of inflammatory bowel disease (such as ulcerative colitis or Chrohn’s disease) increases the risk of bowel cancer.