In the latest in a series of articles on cancer, Dr John Booth, cancer lead for Middlesbrough Primary Care Trust, discusses bowel cancer.

BOWEL cancer is the third most common cancer but it is the second most common cause of death from cancer. There are about 30,000 new cases in England and Wales every year, mainly in people over 50. It is particularly common the North-East and men are slightly more at risk than women.

If the disease is detected early it can be cured. However, at present, the overall cure rate is only about 45 per cent because many patients have advanced disease when they first see their doctor.

Who is at risk and how can it be prevented?

Genetic syndromes: About five per cent of cases have a specific genetic syndrome which puts them at risk of cancer. These people have many relatives with cancer in several generations and often at a young age.

Family history: People with two or more close relatives who developed bowel cancer under the age of 70 are at increased risk.

Colitis: A history of colitis (inflammation in the bowel) increases the risk. However, 75 per cent of patients with bowel cancer have no family history or other condition known to put them at risk of the disease.

Diet: A diet low in fresh fruit and vegetables and high in meat makes bowel cancer more likely.

Lifestyle: Obesity, smoking and heavy alcohol consumption are all associated with increased risk.

Low risk: Exercise, HRT for menopausal women and some anti arthritis drugs seem to protect against the disease.

what are the symptoms?

* Bleeding from the back passage, especially if you are over 50.

* A change of bowel habit persisting for six weeks, especially if the motions become looser.

* Tiredness ( which might be due to anaemia).

* A feeling of incomplete emptying after bowel movements.

* Persistent pain in the abdomen.

* Weight loss.

How is bowel cancer diagnosed?

Colonoscopy: This is the standard test for bowel cancer. If your doctor suspects you might have the disease, he or she will refer you for this test, which is usually done in an out patient clinic. A colonoscope is a fibre optic flexible telescope about as thick as a finger. It can be passed through the anus into the colon (the large bowel) to inspect the lining. Samples of tissue can be taken for analysis and polyps (small swellings on the bowel lining) can be removed. Polyps are not usually cancerous but can become cancer if they are left untreated.

Barium enema: This is a special X-ray using barium liquid in the bowel.

Scan: A CT scan, MRI scan, or an Ultrasound scan can be used to detect any cancer that has spread outside the bowel.

What treatment is available?

Surgery: If the cancer is at an early stage and confined to the bowel, the best treatment is an operation to remove the tumour along with the affected section of colon. This is known as a hemicolectomy and in early stages of the disease, it can be a cure. Sometimes, a temporary colostomy is required to allow the joined ends of the colon to heal without faeces passing through. A colostomy involves making a hole in the wall of the abdomen so that the bowel motions can drain into a bag. The colostomy can often be closed once the colon has healed.

Chemotherapy: Anti-cancer drugs which can kill cancer cells anywhere in the body.

Radiotherapy: Shining radiation onto the tumour to kill the cancer cells.

Palliative care: Treatment to make the patient comfortable and pain free and maintain their health for as long as they live if they cannot be cured.

Is there screening for bowel cancer?

The NHS is currently looking at screening for bowel cancer. The idea is to detect the disease at a very early stage before it has even caused any symptoms. At the moment, some people known to be at high risk are being offered a regular colonoscopy.

It is likely screening will involve two stages, an initial test on the bowel motion to see if it contains blood and if this test is positive, a colonoscopy. Screening of some form will probably be offered to people with a family history of bowel cancer at a young age, patients who have had bowel cancer or polyps and perhaps everybody over the age of 55.

Key things to remember:

* Have a healthy lifestyle, particularly eat fresh fruit and vegetables regularly.

* See your doctor if get any of the key symptoms listed above.

* Don't be embarrassed to talk about the subject.