Bowel cancer screening options, FIT and colonoscopy

What bowel cancer screening is

Bowel screening looks for cancer, and for polyps that could become cancer, in people without symptoms. The UK programme uses the faecal immunochemical test, or FIT, a small stool sample taken at home and posted to a laboratory [1] [2].

Colonoscopy is a direct look at the lining of the large bowel with a thin flexible camera. It can see the whole colon and remove polyps during the same test [3]. Other options include CT colonography, a scan of the bowel, though an abnormal result still leads to colonoscopy [3].

Who it is for and when

In England, people aged 50 to 74 are invited every 2 years, and people aged 75 or over can ask for a kit [2]. The UK National Screening Committee found that FIT screening from 50 reduces deaths from bowel cancer and may help prevent it [1].

In the US, the Preventive Services Task Force recommends screening from 45 to 75, with more choice of test, including colonoscopy every 10 years or a FIT every year [3]. Both approaches are reasonable, and a doctor can explain which fits your circumstances.

The FIT test, benefits and limits

FIT is simple and done at home, and in the UK results are sent 2 weeks after the laboratory receives the kit [2]. A positive result does not mean cancer, and it leads to a colonoscopy to find the cause [3].

A single FIT can miss a cancer or a polyp, which is one reason the test is repeated every 2 years. A normal screening result does not rule out a cause for new symptoms, and NICE advises a fresh FIT to guide referral even after a negative screening kit [4].

Colonoscopy, benefits and risks

Colonoscopy gives the most complete view and can remove polyps before they become cancer. It needs a bowel preparation the day before, a strong laxative that empties the bowel, and this can cause dehydration, particularly in older people or those with other conditions [3].

Serious complications are uncommon, and in screening colonoscopy, US evidence found about 3.1 perforations and 14.6 major bleeds for every 10,000 procedures, with higher rates for colonoscopy after a positive stool test, when more polyps tend to be removed, and risk rising with age [3]. A gastroenterologist explains these risks before you agree.

How you prepare for a colonoscopy and what to expect

Before a colonoscopy, tell the specialist about every medicine, vitamin and supplement you take, because some may need to be paused [5]. You follow a clear liquid diet and take the bowel preparation as instructed, so the camera has a clear view [5].

The test usually takes less than an hour, with a sedative or anaesthetic so you are comfortable, and you rest for about 30 to 60 minutes afterwards [5]. Cramping and bloating are common for the first hour. You cannot drive after sedation, so arrange for someone to take you home [5].

How a family history changes the plan

UK guidelines recommend a single colonoscopy at 55 when one first degree relative had bowel cancer before 50, or two had it at any age [6]. With at least three affected first degree relatives across two generations, they suggest colonoscopy every 5 years from 40 until 75 [6].

People with Lynch syndrome are offered colonoscopy every 2 years, starting at 25 or 35 depending on the gene [6]. If you are unsure about your family history, ask relatives for the type of cancer and the age at diagnosis before you see a doctor.

When screening is the wrong route

Screening is for people without symptoms. A change in bowel habit, blood in your stool, unexplained weight loss, tummy pain or iron deficiency anaemia needs a doctor now, whatever your age or your last screening result [4].

If you are bleeding heavily from the bowel or have severe abdominal pain, call 999 in the UK or the local emergency number.

Questions to ask your doctor

These questions help you agree the right test and the right timing.

• Given my age and family history, is FIT enough for me?
• Would a colonoscopy add anything, and when?
• How should I prepare, and should I stop any medicines first?
• If polyps are found, when would I need another look?

How The Wellness can help

A GP appointment with a GMC registered doctor helps you decide which test suits your age and family history, and whether a specialist is needed. When colonoscopy is right, navigation finds a gastroenterologist for your case and books the first appointment, offered within 48 hours when it is urgent and within 5 working days when it is routine [7].

The specialist and the procedure are billed by the people who provide them, and we tell you the fee before you agree. Every letter and result comes back into your record, read by your doctor, and navigation is included in membership [7].