Caught early, this disease has an excellent cure rate, but people with tell-tale symptoms are often too scared or embarrassed to seek help. Dr Josephine Fagan gives us the facts.
Why the panic?
Bowel cancer mortality rates are baffling, but to quote Cancer Research UK, “Mortality statistics… don’t mean much. They have to be looked at alongside incidence figures and… don’t take account of stage, grade or any specific sub-type of a cancer.”
Some more meaningful numbers:
•One in 14 men, and one in 19 women, have a lifetime risk of developing bowel cancer, which means all of us have a significant chance of being affected by the disease.
•NHS records show 40,000 new cases of bowel cancer are diagnosed each year
•In the UK, between 15,000 to 16,000 people die from bowel cancer each year
But it’s not all bad news:
•Five year survival rates for bowel cancer have doubled over the last 40 years
•According to Cancer Research UK, 93% of people diagnosed with bowel cancer at an early stage survive for at least five years compared with less than 7% of those diagnosed at a late stage. (And there’s the rub…)
What is bowel cancer?
Bowel cancer is another name for colorectal cancer and can affect any part of the colon or rectum – parts of the so-called large bowel, or large intestine. (It’s possible to develop cancer in the small bowel, but much rarer.)
Illustration by Dr Josephine Fagan
What are the symptoms?
It’s possible be symptom free. Early signs can be subtle and may include:
•Blood or mucus in stools
•Opening your bowels more often (for three weeks or more)
•Looser stools (for three weeks or more)
•Alternating bouts of diarrhoea / constipation
•A sensation of not having fully emptied the rectum after passing a motion
As the cancer grows, symptoms may also include:
•Tiredness, often due to anaemia from ongoing blood loss in the stools
•Severe abdominal pains due to bowel perforation or blockage of the bowel
•Symptoms from other parts of the body, if the cancer has spread
A word of warning: many of the above symptoms are associated with other non-cancerous conditions, including IBS. If in doubt, consult your doctor.
What are the main risk factors?
•Age – it’s more common in the over 50s, although it can occur in younger people
•Lifestyle – smoking, alcohol, lack of exercise, eating too much processed meat and not enough fibre, and being overweight
•People who have had ulcerative colitis, or Crohn’s disease for more than eight years have an increased risk
•Genetics – the risk of developing bowel cancer increases if a close relative has been affected
•Two rare inherited disorders also carry an increased risk: familial adenomatous polyposis coli, and Lynch Syndrome (also known as hereditary non-polyposis colorectal cancer).
Are there any protective factors against bowel cancer?
Yes. Women taking HRT, people who eat lots of fruit and vegetables, and people taking aspirin for other medical conditions all appear to have a lower risk.
However, as aspirin can cause bleeding from the stomach, it isn’t currently recommended simply to lower the risk of developing colorectal cancer. Advice on this may change.
What happens if you and your doctor suspect you have bowel cancer?
Your doctor will examine your abdomen and back-passage (to see if there is a tumour inside the rectum). This initial examination is often normal. To investigate further, you may be sent to see a specialist for various tests, most commonly a colonoscopy or flexible sigmoidoscopy, which involve a flexible camera being inserted into your bottom to take a closer look at the bowel. A biopsy may be taken. CT colonoscopy, which uses X-rays to form a detailed picture of the bowel, may also be used.
What if a polyp is found?
If polyps are found at colonoscopy, they can be removed there and then. Most don’t contain cancer cells but some have the potential to turn cancerous; others may contain cancer cells that have not spread, so removing these polyps removes the cancer risk.
If a polyp contains cancer cells that show signs of having spread, further tests and treatment are required.
What’s the reality for those with bowel cancer?
If a diagnosis of bowel cancer is confirmed, further investigations, such as MRI scans, are done to see if the cancer has spread. This process of assessment is called ‘staging’ or ‘grading’ the cancer. Without getting into too much jargon, one frequently used system is the Duke’s Classification:
•Duke A: the cancer is confined to the inner lining of the bowel or rectum
•Duke B: the cancer has extended into the muscle layer of the bowel or rectum
•Duke C: the cancer has spread to one nearby lymph node
•Duke D: the cancer has spread to other organs, (usually liver, lungs or brain – these secondary tumors are called metastases)
Staging bowel cancer enables specialists to give personalized advice on treatment options and expected outcomes, taking into account an individual’s general health. Options may include surgery, chemotherapy and radiotherapy, but I’ll leave the nitty-gritty of specific treatments and their prognoses to the experts.
What’s the take home message?
According to the National Cancer Intelligence Network:
•People diagnosed with early bowel cancer (grade A) have more than a 9 in 10 chance of surviving the disease. Unfortunately, only 1 in 7 people are diagnosed at this stage, partly because colorectal cancer may cause no symptoms at first.
•If the diagnosis is made in the later stages of the disease, five year survival rates can be as low as 7%. That’s why screening is important: it could help to increase the number of early diagnoses and good outcomes.
What is being done to spot it sooner?
Screening programmes are in place to pick up early signs of disease in apparently healthy people.
•The test routinely offered to screen for bowel cancer in the UK is the Faecal Occult Blood Test (or FOB), which can detect traces of blood in stools. The test kit is posted out to patients and is easy to use.
•Flexible sigmoidoscopy is another means of screening but, at present, it’s mainly used to screen high-risk individuals.
What can we do about bowel cancer?
•If you think you have symptoms, consult your doctor.
•If and when you’re offered a FOB test kit, use it.
•If you have a friend or family member who is worried about symptoms, encourage them to see their GP
•If you know someone who has bowel cancer, be supportive and encourage them to get the right professional help and advice.
Josephine works as a doctor in urgent and primary care. She’s also a bit of a globetrotter, is working on her first novel, and loves the colour purple.