Colorectal cancer is one of the most common cancers worldwide.
Fortunately, it is also one of the most preventable cancers with the help of screening. Colorectal cancer develops from polyps, but polyps do not have symptoms. However, the removal of polyps (polypectomy) in turn prevents it from developing further into colorectal cancer. This is how screening via Colonoscopy helps prevent colon cancer.
Early-stage curable colorectal cancer has virtually no symptoms, but screening via Colonoscopy again helps with the early detection of colorectal cancer. Early-stage colorectal cancer has a 5-year survival rate of 80-90%, and early detection is key.
A colonoscopy is routinely offered to adults above the age of 50 for screening for polyps and also early detection of colorectal cancer. Those with the following risk factors are at higher risk for colorectal cancer and should consider earlier screening:
- A family history of colorectal cancer
- Genetic syndromes like familial adenomatosis polyposis or HNPCC
- A personal or family history of inflammatory bowel diseases
- Being overweight
- Having Type 2 diabetes
- Consuming a high-fat diet
- Drinking alcohol regularly
- Not exercising regularly
Your doctor may also recommend a colonoscopy if you show symptoms suggestive of cancer, such as blood in your stools or unexplained abdominal pain or changes in your bowel movement habits.
Colorectal cancer is the most common cancer in males in Singapore and the second most common for females in Singapore, making routine colonoscopies important.
Most people are recommended to go for a colonoscopy at 50 years old for preventive screening. Colonoscopies should then be done every five years until age 75.
On the other hand, colonoscopies are recommended in your late 30s or early 40s if you have:
- A first-degree relative (parents or siblings) with colorectal cancer
- A family history of colorectal cancer syndromes like familial adenomatous polyposis or HNPCC
- A diagnosis of inflammatory bowel disease (IBS).
- A personal history of having certain cancers or polyps.
A colonoscopy takes about 30 minutes to complete and you will be able to go home on the same day.
Before going for a colonoscopy, you are recommended to arrange for a day of leave on the day of the scope.
Bowel preparation is important in the days leading up to the colonoscopy.
The type of food you should avoid include:
- Nuts and seeds
- Juices with fruit pulp
- High fibre food
- All vegetables
- Brown rice and wholemeal bread
- Cereals and oats
You are only required to abstain from food about 6-8 hours before the scope. You can continue to drink water until 2hrs before your scope.
You will also be prescribed bowel clearance medications that will bring you to the toilet about 7-10 times to clear your colon.
Before the procedure, most patients are put under IV sedation to ensure a comfortable procedure. You will be unaware of the proceedings during the scope. You will then be positioned to the side, with your knees curled towards your torso.
A long, flexible and thin tube with a miniature camera and attached light (colonoscope) will be inserted into the rectum via the anus. This allows your doctor to visualise the gastrointestinal tract for any polyps, tumours, vascular malformations or any other structural abnormalities that line your gut.
Polyps can be removed (polypectomy) via instruments inserted through the colonoscope by snipping off the tissues or burning them with electrocautery. Similarly, if your doctor detects any abnormalities, they can obtain a biopsy for further examination, if needed. These procedures do not cause any pain both during and after the procedure.
Your personal or company insurance plans do cover colonoscopies performed for specific symptoms.
For self-paying individuals or those who wish to do screening in the absence of symptoms, our clinic offers a screening package that allows utilisation of your Medisave with only a small cash outlay.
Complications are rare after a colonoscopy. You will also not experience much discomfort beyond some abdominal bloatedness.
Please contact us immediately if you experience the following symptoms after your procedure:
- Chest pain
- Shortness of breath
- Bloody, black or very dark coloured stool
- Chronic or intense abdominal pain
Once you reach the age of 50, you are recommended to go for routine colonoscopies every 5 years.
However, if you have symptoms of any gastrointestinal or colorectal conditions within the 5-year period, you are recommended to come in for a repeat exam earlier.