How to check whether you have bowel cancer

Dawson's Creek actor James Van Der Beek has died at the age of 48 from bowel cancer.

What are the main symptoms and causes of the disease, and how can you reduce your risk of getting it?

There are three main things to look out for:

• blood in your poo for no obvious reason - it may be bright or dark red
• a change in how you poo - such as going to the toilet more often or your poo becoming runnier or harder
• feeling lower tummy pain or bloating, when your belly feels full and tight

There may be other symptoms too, such as:

• losing weight
• feeling you haven't emptied your bowel properly after a poo
• feeling more tired or dizzy than usual

Having these symptoms doesn't necessarily mean it's bowel cancer.

But the NHS recommends that you see your GP if you notice them for three weeks or longer, and if things just don't feel right.

Sometimes bowel cancer can stop waste passing through your system, which can cause a blockage.

This can bring on severe tummy pain, constipation and sickness. You should see your GP or go to your nearest A&E straight away in those circumstances.

Look out for blood in your poo as well as bleeding from the bottom when you go to the toilet.

Bright red blood may come from swollen blood vessels (piles) in your back passage, but could also be caused by bowel cancer.

Dark red or black blood in your poo may come from your bowel or stomach, and could also be worrying.

You may also notice a change in your bowel habits, such as looser poo, pooing more often than normal, or a feeling that you're not emptying the bowels properly.

Bowel Cancer UK recommends keeping a diary of your symptoms which you can discuss with your GP.

Doctors are used to seeing lots of people with a variety of bowel problems, so there is no need to be embarrassed.

No-one is sure exactly what causes it, but there are some things which can make it more likely:

• the older you are, the more likely you are to get cancer - most cases of bowel cancer are in adults over 50, although rates are rising among younger people
• eating a diet with lots of red meat and processed meat, such as sausages, bacon, salami
• having a history of polyps in your bowel which can grow into tumours
• smoking cigarettes can increase the risk of developing many cancers
• drinking too much alcohol
• being overweight or obese

In most cases, bowel cancer isn't hereditary but you should tell your GP if you have any close relatives diagnosed before the age of 50.

Some genetic conditions such as Lynch syndrome mean you have a much greater risk of developing bowel cancer. But doctors can work with patients to try and limit the additional risk, and ensure they are diagnosed at an earlier stage when it is easier to treat.

More than half of bowel cancers could be prevented by people following a healthier lifestyle, scientists say.

• exercising more
• eating more fibre and less fat
• drinking six to eight glasses of water a day

You should also go to your GP with any concerning symptoms, and take up the offer of cancer screening as soon as it is offered.

The NHS bowel cancer screening programme aims to detect bowel cancer at an early stage across the UK.

But it's not available to everyone - only to those age groups most likely to benefit. Screening isn't 100% accurate, and can lead to harm and unnecessary treatment if lots of healthy people are tested.

In England, Scotland and Wales, screening starts from age 50.

In Northern Ireland, it's for people over 60.

You will receive a home test kit to help gather a poo sample which you send back to be analysed.

You will then either be given the all-clear or contacted by your local hospital for further tests.

These could be a colonoscopy - a procedure which uses a camera inside a long tube to look inside the whole bowel - or a flexible sigmoidoscopy, which looks at part of it.

If you're in a younger age group and have symptoms, you should visit your GP but are not advised to buy a self-test kit, because the results can be confusing.

Treatments are becoming more personalised, as advances in genetic testing mean care can be tailored to the way each individual deals with their body's own cancer.

This approach still needs refining, but could mean extra years of life for those with cancer.

At whatever stage your cancer is spotted, you will be talked through the treatments available.

That might be surgery, or a combination of chemotherapy and radiotherapy, depending on your individual cancer.

Bowel Cancer UK has advice on questions to ask at appointments with specialists.

Bowel cancer is curable, especially if diagnosed at an early stage.

• stage 1 cancers - small, but haven't spread
• stage 2 cancers - larger, but still haven't spread
• stage 3 cancers - have spread to some of the surrounding tissue such as lymph nodes
• stage 4 cancers - have spread to another organ in the body, creating a secondary tumour

More than 90% of people diagnosed with bowel cancer at its earliest stage will survive for five years or more - compared with 44% when diagnosed at the latest stage.

The chances of survival in the UK have more than doubled in the last 40 years - more than half of patients now survive for 10 years or more, compared with one in five in the 1970s.

Like many cancers, 15 to 40-year-olds have the highest survival rates, because cancer is more common and more deadly in older people.

However, in general, survival is not as good in the UK as the rest of Europe.