The Big C Series: A Highlight On Bowel Cancer

Bowel cancer is the third most common cancer worldwide and so it wouldn’t be right to have a month focussed on gut health without talking about it. It mostly affects the over 50s age group with factors such as excessive processed foods, smoking and alcohol increasing the risk (1).

So when should you worry about colorectal cancer? The Northern Ireland Cancer Network sets out a series of red flag symptoms and signs that may represent a bowel cancer. These include:

• Rectal bleeding

• Change in bowel habit of more than 4 weeks

• Feeling of a mass in the abdomen

• Iron deficiency anaemia without an obvious cause

• Abdominal pain with weight loss

If you have any of these symptoms it does not necessarily mean you have cancer but that you do need urgent further investigation (2).

To further decide whether your symptoms are likely to be related to cancer your GP will advise you to do a stool sample for a test called a QFIT. QFIT stands for quantitative Faecal Immunochemical Test and it looks for broken down blood in the stool.

The QFIT stool test has really transformed the way we test for bowel cancer and had reduced the number of invasive tests such as colonoscopies needed to rule out a cancer.

For example, if your QFIT test is negative for broken down blood (in trials this is 19 ng Hb/g or less) then there is a 99.5% chance of having a normal colonoscopy. On the other hand if your QFIT test is more than 19 ng Hb/g then there is a 15.1% chance of finding a cancer on a colonoscopy.

In basic terms if your QFIT test is negative it is very unlikely you have cancer but if it’s positive there’s still a good chance it’s not cancer but you’ll need investigations such as a colonoscopy a bit quicker (3).

If you are diagnosed with bowel cancer at its earliest stage then 5 year survival rates are high at around 90%. Unfortunately at later stages survival rates decrease dramatically, so it’s important to contact your GP as soon as you notice symptoms (4).

So what about a screening programme for bowel cancer? Bowel cancer screening started in 2010 in Northern Ireland and continues to be offered on a 2 yearly basis to adults aged 60-74. It takes the form of a QFIT test which is posted off to look for broken down blood (5).

Regular bowel cancer screening has been shown to reduce the chances of dying from bowel cancer by 16%. Other things you can do to reduce your risk of getting bowel cancer are eating a healthy diet, weight reduction and regular exercise. More information on this can be found on the NI Direct website which I will link below (6).

In special cases such as a family history of bowel cancer, you may need additional screening with regular colonoscopies. Bowel Cancer UK discusses the need for additional screening on their website and if you fit into these categories then your GP can refer you (7).

References:

1. https://www.who.int/news-room/fact-sheets/detail/colorectal-cancer

2. https://nican.hscni.net/wp-content/uploads/2024/09/NICaN-Suspect-Cancer-GP-Referral-Guidance-10th-June-2024-qFIT-threshold-1.pdf#page6

3. https://bkpg.org/content/71/709/e643

4. https://www.cancerresearchuk.org/about-cancer/bowel-cancer/survival

5. https://www.publichealth.hscni.net/directorate-public-health/service-development-and-screening/bowel-cancer-screening#:~:text=The%20bowel%20cancer%20screening%20programme%20started%20in%20Northern%20Ireland%20in,screening%20kit%20every%20two%20years.

6. https://www.nidirect.gov.uk/bowel-screening#toc-10

7. https://www.bowelcanceruk.org.uk/about-bowel-cancer/risk-factors/family-history/