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FIT is an attractive option to many people because it ’ s non-invasive and easy to do as people can collect the sample at home . lay audience is : if you have a family history of colon cancer , talk to your doctor ,” advised Dr Dominitz .
Complicating matters more is that these guidelines only apply to people who have no symptoms . Anyone experiencing a health problem that may point to colorectal cancer is strongly advised to see a doctor regardless of their age because some tests may be required to rule out colorectal cancer . Potential symptoms include blood in the stool , unexplained weight loss , difficulty having a bowel movement , or significant changes in bowel habits .
For instance , “ if the stool is very thin , often referred to as ‘ pencil-thin ’ stool , instead of being a normal bowel movement , that would suggest there may be some kind of a mass in the rectum ,” explained Dr Dominitz .
The most common screening examinations Though there ’ s an array of screening options for colorectal cancer , the two most common examinations across several countries are the faecal immunochemical test ( FIT ) and colonoscopy . The former involves collecting a stool sample that ’ s analysed in the lab to detect tiny blood traces , while the latter requires a camera-equipped tube to be inserted through the anus into the colon to look for cancer or polyps and potentially remove them .
FIT is an attractive option to many people because it ’ s non-invasive and easy to do as people can collect the sample at home . Several studies have shown it can successfully detect about seven out of 10 colorectal cancers . Therefore , people who test positive with FIT have to undergo a colonoscopy to determine the source of blood — pre-cancerous polyps can cause
A polyp which can turn into colon cancer . blood in the stool , but FIT could also lead to a false positive .
Colonoscopy can provide more solid answers because doctors can see potential cancerous growths directly while cutting bits of them to analyse in the lab and check whether they are the result of malignant cells or not . Importantly , most polyps can be removed during colonoscopy before they have time to progress to cancer . But it ’ s an invasive procedure requiring people to avoid food for several hours while taking laxatives to empty the bowels as much as possible to facilitate visualisation . Though it ’ s safe in most cases , it can occasionally lead to complications , including a bad reaction to the pain medicines used during the procedure , nausea , and vomiting . More serious problems can also occur .
“ Approximately one out of 700 patients has a serious bleeding complication and one out of 3,200 has a perforation , that is a hole in the colon that typically requires surgery to repair ,” said Dr Dominitz .
The difference in cancer detection rates between the two tests is the main reason FIT is usually recommended every one to two years , while colonoscopies should be done every 10 years if no precancerous polyps are detected . This is because it takes about 10 to 15 years for normal tissue to turn into colorectal cancer , experts believe . So regular screening offers multiple opportunities to detect cancer .
However , while most experts agree that a colonoscopy is essential for colorectal cancer screening in combination with positive stool tests , a more heated debate surrounds its use as a standalone screening test for average-risk people .
Countries like the United States and Singapore recommend either a stool test or a colonoscopy as standard screening for people without specific risk factors for colorectal cancer , like family history of the disease . But many other national health authorities , such as in the UK , Italy , and Norway , only advise their citizens to use a stool test , either FIT or a similar one called guaiac FOBT , while recommending a colonoscopy only to people who tested positive .
The research on colonoscopy This difference in protocols is mostly due to diverging interpretations of the research findings around the efficacy of colonoscopy as a screening method .
Several cohort studies , which looked at thousands of people who either developed colorectal cancer or didn ’ t , showed that doing a colonoscopy was associated with a 60 to 70 percent reduced risk of having the disease , explained Dr Dominitz , adding such studies and other research led US health authorities to recommend colonoscopy as a colorectal cancer screening option for average-risk individuals . “ The problem with cohort studies is that people who get a colonoscopy are not randomly selected ,
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