Think bowel cancer can’t happen to you – or just don’t want to think about it at all? Accredited Practising Dietitian Bobbie Crothers lifts the lid on why bowel cancer screening is so important.
When most people hear the phrase ‘bowel cancer’, they switch off. “It’s an old person’s disease”, some may think; others simply don’t believe it could happen to them. For many people, it’s just too unpleasant to discuss. But believe it or not, there has been a 64% increase in the incidence of bowel cancer among 20–34 year-olds since the mid-1990s. So it’s time bowel cancer stops being a taboo topic and becomes a common conversation.
Who does bowel cancer affect?
Bowel cancer (also known as colorectal cancer) refers to cancer of the rectum or colon. It is the most common internal cancer in Australia – and the second leading cause of cancer death after lung cancer, says Professor Terry Bolin, President of The Gut Foundation. Around 30 people are diagnosed with bowel cancer every day – 12 of whom will die because it’s diagnosed too late, he says.
Bowel cancer affects both men (around 1 in 18) and women (around 1 in 27). About one in 10 bowel cancers occur in people under the age of 50 – and the risk doubles each decade after the age of 50. With a large part of the population over 50 – and bowel cancer increasingly affecting all age groups – it’s more important than ever to be aware of the risks, screening processes and treatment options available. The government has initiated a National Bowel Cancer Screening Program for people age 50 and over – ask your doctor if you are eligible to participate.
While for some people it can be embarrassing, bowel cancer is a topic that should be discussed with your doctor and family.
What causes bowel cancer?
Bowel cancer is caused by the uncontrolled growth of abnormal cells which form a tumour within the lining of the bowel or rectum. Most cancers of the bowel develop from small growths called polyps, however not all polyps are cancerous. The development of these polyps – and whether they will become cancerous – depends on genetic factors (such as family history) and environmental and lifestyle factors, with diet and inactivity being the main lifestyle contributors.
What are the risk factors?
There are only a few known risk factors for bowel cancer, including:
Being 50 years and over
Having close relatives (mother, father, sibling or child) who have had bowel cancer or polyps
Having had bowel cancer or polyps before
Having inflammatory bowel disease, such as ulcerative colitis or Crohn’s disease.
However, four out of five people who develop bowel cancer have no known risk factors.
Symptoms you should look for
There are very few symptoms of bowel cancer, and they may not appear until the cancer is in its advanced stages. That’s why it’s so important to act quickly if you notice any of the symptoms below:
Blood (either bright red or very dark) in the stool
A persistent change in bowel habits like diarrhoea, constipation or feeling that the bowel does not empty completely
Frequent gas pains, bloating, fullness or cramps
Stools that are narrower than usual
A lump or mass in your tummy
Weight loss for no known reason
Persistent, severe abdominal pain, which has come on recently for the first time
Feeling very tired
If you have any of these symptoms, it doesn’t necessarily mean you have bowel cancer – but it’s very important you check with your doctor.
Additionally, no matter your age, never let your doctor tell you that you are too young to have bowel cancer – it is increasingly affecting all age groups.
What if I see blood in my stool?
If you do see blood in your stool, or there is blood when you go to the toilet, your doctor may perform a physical examination via the rectum. This involves the doctor examining the rectum with their finger to check if there is any bleeding in the rectum and to feel for any abnormalities. The doctor will then determine if a colonoscopy is required.
Investigation and screening
While we know bowel cancer is the second most deadly form of cancer, the good news is that it is the only potentially preventable internal cancer in men and one of two preventable cancers in women (the other being cervical cancer). This makes awareness of the risks and symptoms – and early detection via screening – vital.
A recent report from the US shows the effectiveness of getting screened: between 2002–2010, bowel cancer screening increased from 52 per cent to 65 per cent in people aged 50–75. The incidence of, and death from, bowel cancer declined significantly in most US states over the same period. It just goes to show that overcoming your embarrassment, talking to your doctor about your risk of bowel cancer and then getting screened, could save your life.
How do doctors screen for bowel cancer?
The two main methods used to screen for bowel cancer are:
1. Faecal occult blood test (FOBT)
Most tumours and large polyps bleed, however blood can be present in such small amounts that it goes unnoticed. An FOBT identifies if you have any blood in your stool. The test is very simple and you can do it yourself at home – it’s quick, easy, painless and non-invasive.
The test involves placing a small sample of your stool on special cards and posting them to a pathology lab for analysis. The results are sent back to you and your doctor about two weeks after you post the samples. You can buy an FOBT kit from your pharmacy for around $35.
Some FOBTs use less specific methods to detect blood which require dietary changes before you take the test, so read the instructions carefully beforehand.
While the process is simple, one issue with an FOBT is that a cancer or polyp needs to be bleeding at the time you undergo the test, meaning a negative test doesn’t rule out cancer or polyps completely.
Many health professionals and health organisations suggest you have an FOBT to screen for bowel cancer every two years from the age of 50. However, Professor Bolin recommends screening start at 40 years of age and be carried out annually, since screening is essential for prevention and early diagnosis. Studies have shown that an FOBT performed every 1–2 years in people age 50 and over can help reduce the number of deaths from bowel cancer by 15–33 per cent. If you get a positive result from your FOBT, it must be followed by a colonoscopy.
A colonoscopy is the most sensitive and specific method for examining and diagnosing issues within the bowel. Biopsies, the removal of polyps and other operations can also be undertaken during a colonoscopy if necessary. Colonoscopies can help reduce the number of deaths from bowel cancer by up to 90 per cent.
So what should you expect if you have a colonoscopy? First, the bowel needs to be empty during the procedure to allow a clear view of the inside of the bowel. The day before a colonoscopy, you will need to drink a solution called ‘bowel prep’ from midday and over the course of the afternoon. The solution acts as a powerful laxative to flush out the bowel – which means you will be going to the toilet often and motions may be soft, a little like you have a touch of diarrhoea. No food is allowed from midday the day before, but you can have clear fluids.
During the procedure, a colonoscope – a long, flexible video instrument – is inserted into the anus and up through the entire bowel. Patients are usually awake but sedated during a colonoscopy, so it isn’t painful. The procedure itself usually takes only about half an hour, depending on the findings and whether any polyps need to be removed. Most people are in and out of hospital on the same day and can be back to work the next day, depending on how quickly they recover from the sedatives.
A colonoscopy is seen as the gold standard method for examining the bowel for polyps and cancer. Where age is the only risk factor for bowel cancer, a colonoscopy is recommended every 5–10 years. If you have other risk factors, talk to your doctor about scheduling colonoscopies more often.
Too embarrassed for testing?
One of Bowel Cancer Australia’s aims is to prevent Australians from ‘dying of embarrassment’ – which shows just how squirm-inducing the idea of being tested is for many people. It’s important to remember that doctors talk about, and conduct surveillance and screening tests, for bowel cancer every single day, so there is no need to be embarrassed. If you’re really anxious, talk to your doctor beforehand about each step of the process to remove some of the mystery. Remember, a few minutes of discomfort is far better than a battle with cancer.
How does my diet affect my risk?
Environmental factors, such as what you eat, are thought to play a big part in the incidence of bowel cancer. When it comes to minimising your risk of bowel cancer, it’s important to follow general healthy eating advice, says Katherine Collings, research dietitian at The Gut Foundation.
Eating less fat (especially saturated fat); more high-fibre foods such as high-fibre and wholegrain breads and cereals; and plenty of fruits, vegetables and legumes is recommended. A high consumption of meat and processed meat is considered a major dietary risk factor for bowel cancer, says Professor Bolin.
However, while there is a link between high meat consumption and bowel cancer, this doesn’t mean you need to switch to a vegetarian diet – vegetarians can still suffer from this disease, says Collings. Aim for 3–4 servings of lean meat per week and minimise your intake of processed meats (this includes salami, ham, bacon, sausages, hot dogs and luncheon meats).
Professor Bolin also highlights other important risk factors including smoking, alcohol and obesity, and the importance of getting enough of a variety of other nutrients, such as calcium and selenium, which can be obtained from a normal healthy diet that includes cereal, fibre, dairy, fruit and vegetables.
Ways to help reduce your risk
Get screened: Talk to your doctor about a prevention program, especially if you are 40 years or older.
Always look before you flush: See your doctor immediately if you notice blood in the toilet bowl or on your toilet paper, or if your poo is black or appears to contain blood.
Know your bowels: If you have persistent changes in bowel movements like diarrhoea, constipation or abdominal pain, talk to your doctor – while these symptoms can have many causes, it’s best to get them checked out.
Limit alcohol: If you drink, do so in moderation (no more than two standard drinks per day and two alcohol-free days per week) and limit consumption of beer, as it’s thought to be linked with bowel cancer, according to a Canadian study conducted in 2002.
Follow a healthy balanced diet: Eat plenty of fibre-rich foods, fruits, vegetables and legumes (aim for 30g fibre each day) and high-calcium foods. Decrease your fat and saturated fat intake.
Exercise regularly: Aim for 30 minutes a day – it doesn’t have to be all at once.
Maintain a healthy body weight: Obesity has been linked with colorectal cancer in several studies.
Don’t smoke: If you do smoke, speak to your doctor about an approach to quitting that’s right for you.
Lyndel Walsh, 46, continues to fight the disease after being diagnosed with bowel cancer in 2009. Here's her story.
“Early in 2008, I knew something was not quite right. I was extremely tired, lethargic and had very irregular bowel movements. Ongoing diarrhoea, straining while trying to pass soft motions and many of what I like to call ‘free steak knife moments’ (…but wait, there’s more!) – thinking I’d finished only to realise I needed to go again straight away. I knew I needed to go to the doctor and have it checked out, but I just put it off.
“In June 2008 I ended up in hospital (for an unrelated issue), which gave me another reason to put off going to the doctor about my bowel issues and what I thought were haemorrhoids from an earlier pregnancy.
“In October that same year I started to notice a lot of bleeding when I was going to the toilet, which finally pushed me to see my GP in November for a referral to a specialist to see about my haemorrhoids. When the specialist stopped mid-examination and told me we’d have to look at the haemorrhoids another day, I immediately knew something was wrong. He told me I had a rectal adenocarcinoma. My initial reaction was: “I’m only 44 years old – this is an old person’s disease. This can’t be right!”
“The next step was a full body scan to check if the cancer had spread. It had – I had liver and lung cancer as well. At this stage, I could hear my mother’s words ringing in my ears... “Have you been checked? Have you had a bowel cancer test?”. My mum had been diagnosed with bowel cancer 12 years earlier and my dad had had numerous bowel polyps removed. Having bowel cancer in the family meant I was at increased risk. I should have been more proactive.
“My doctor said I had a less than 50% chance of living another two years, but I wasn’t having any of that. The next steps were having 25cm of my bowel removed, a stoma bag attached while I recovered from the surgery, and intense chemotherapy.
“The chemotherapy continues today, and that’s the plan until a cure is found. While it’s a harsh reality, I need to keep positive. That’s how I keep on going and how I attack every day.
“My advice to everyone is: do not put off being tested! If something doesn’t feel right, see your doctor. I had an FOBT in 2006 (which was clear), missed my 2007 scan and in 2008 things started to go wrong. The FOBT test is the easiest, cheapest and least intrusive test to screen for bowel cancer. It’s just so important not to put things off when it comes to your health. Being healthy and fit, eating well and exercising every day doesn’t mean you’re immune to this disease. Bowel cancer can affect everyone and doesn’t discriminate, but unlike many other cancers, you can do something about it!”
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