Bowel cancer: Everything you need to know

Bowel cancer symptoms are often hard to notice in the early stages, but early intervention is key to successful treatment outcomes. We look at bowel cancer in Australia, early symptoms and diagnosis, and how you can access regular screening.

Bowel cancer (or colorectal cancer) starts on the inner lining of the bowel as benign growths called polyps. These growths can become cancer if left untreated.¹

In Australia, bowel cancer is the fourth most common newly diagnosed cancer and the second deadliest cancer, although up to 99% of bowel cancers can be treated successfully when found early.²

While bowel cancer is still more common in older adults, over the past 30 years there has been a 266% increase in people aged 15 to 24 being diagnosed.²

It's essential to know the risk factors, signs and symptoms of bowel cancer so you can get tested and, if necessary, seek treatment as soon as possible.

It's unclear why early-onset bowel cancer is on the rise globally. While more research is needed, colorectal surgeon and Bowel Cancer Australia spokesperson Dr Penelope De Lacavalerie says there may be a number of factors at play.

"There are several hypotheses about why we are seeing more bowel cancer, especially in people under 50," says Dr De Lacavalerie. "One is the use or overuse of antibiotics in early life, which we know can impact the bowel lining and the gut microbiome. Childhood obesity has also been linked to the increase in bowel cancer, as has our diets.

"We eat a lot more processed foods than previous generations, not enough fibre and too much meat. These are all potential risk factors for bowel cancer."

Bowel Cancer Australia recommends eating no more than 300 to 500g of cooked meat per week (about 3 portions), avoiding processed meats altogether, and eating 400g of dairy products per day to help reduce your risk of bowel cancer.³ It also recommends eating at least 90g of wholegrains a day, such as brown rice, oats, quinoa, corn or wholemeal bread.

Bowel cancer can be present without any symptoms and so regular screening is important, especially if you have a family history of bowel cancer, polyps, Crohn's Disease or ulcerative colitis.^4,5

According to Bowel Cancer Australia, common symptoms of bowel cancer include:

• B: Blood in your poo
• O: Obvious changes in your bowel habit
• W: Weight loss you can't explain
• E: Extreme tiredness for no reason
• L: Lump or swelling in your abdomen.

While these are common symptoms, they don't always mean you've got bowel cancer so it's important not to panic. However, these symptoms should never be ignored, and you should seek medical advice if you notice any of them.

"If you have symptoms, you need to see your GP," says Dr De Lacavalerie. "Any blood in the stool is not normal and should be investigated with a colonoscopy. Know what's normal for your body and seek help if anything changes or is unusual for you."

Anyone can be diagnosed with bowel cancer. However, there are some factors that may put you at a higher risk.

Risk factors for bowel cancer include:

• being aged 50 or older
• a family history of bowel cancer and polyps
• the presence of Crohn's disease or ulcerative colitis
• being overweight or obese
• having a sedentary lifestyle with little physical activity
• high intake of particular foods (such as red and processed meats)
• low blood level of vitamin D
• alcohol consumption
• smoking
• having type 2 diabetes.⁵

If you have symptoms or receive a positive result from a bowel cancer screening test, your doctor will refer you for further tests (such as a colonoscopy) that can help detect polyps and sometimes cancer).

Your specialist and doctor will discuss the results of your test with you, and if you are diagnosed with bowel cancer they will discuss your treatment options.

This may include surgery and/or other cancer treatments such as radiotherapy, chemotherapy or immunotherapy.⁶

The type of treatment you receive will depend on a number of factors including the stage of the cancer.

Some people with bowel cancer may need to have a permanent or temporary stoma bag. This is where faecal matter is collected into a bag outside of the body, through a small opening in the abdomen.

"Early treatment leads to better outcomes," says Dr De Lacavalerie. "In the absence of an emergency, approximately 3% of bowel cancers require the patient to have a stoma bag. Even when that number rises to 10 to 20% where there is an emergency present, many stomas are reversible."

Talk to your healthcare team about what you can expect from your treatment plan.

If you are diagnosed with bowel cancer, it's common to feel a range of emotions.

It's important you share these feelings and concerns with your doctor, as your emotional wellbeing is just as important as your physical health.

There is support available for you and your loved ones, and your medical team can connect you with services such as counselling and support groups that can help.

"Many of my patients experience a lot of anxiety, not only with the diagnosis but also about their future life," says Dr De Lacavalerie. "Finding an outlet such as exercise or meditation can help both the mental symptoms and help support physical recovery. Support groups, such as Bowel Cancer Australia's, help to connect people who have bowel cancer which can be very helpful."

Developed in 2006, Australia's National Bowel Cancer Screening Program is now available to people aged between 45 and 74 years old.

Aiming to reduce the number of deaths from bowel cancer, the program is available to people with no symptoms and works by sending at-home test kits every 2 years. Over 50s will automatically receive a test kit in the mail and do not need to register.

If the results show there is blood in the stool, you will be contacted to organise further tests (such as a colonoscopy) to investigate if bowel cancer is present. If no blood is detected, you will be notified and will receive a follow up test every 2 years.

If you are aged 45 to 49, you can opt-in and will receive a test kit every 2 years with the National Bowel Screening Program.

If you are aged 50 to 74, you will receive a test kit in the mail. If you do not receive one, speak to your GP or request a test kit online.

If you are outside of the age limits and would still like to be screened for bowel cancer, speak to your GP.

"Only 40% of people who receive the test actually do it, so the most important message I can give is: do the test!" says Dr De Lacavalerie. "We cannot provide treatment unless we know bowel cancer is present." According to Dr De Lacavalerie:

If you have any concerns about your health, talk to your GP.

"Don't be afraid of asking for a colonoscopy or even a second or third opinion if you feel you aren't getting the correct information," says Dr De Lacavalerie, who says we must advocate for ourselves. "No one is too young to get bowel cancer, so know what is normal for you and seek help if things change."

Bowel Cancer Australia has information online for patients and their families, plus free resources to download about every stage of diagnosis and recovery.

The National Bowel Cancer Screening Program details everything you need to know about how to access the at-home kit and important next steps.