Medical Director
Senior Consultant, General & Colorectal Surgeon
MBBS (Singapore), MRCS (Edinburgh), MMed (Surgery), FRCS (Edinburgh)
What is a Colonoscopy?
A colonoscopy is often touted as the “gold standard” of colorectal cancer screening, being the most accurate and efficient method available.
With timely colonoscopies, one can even detect and remove pre-cancerous growths, so that they do not even progress into cancer.
With colorectal cancer being the most commonly diagnosed cancer in Singapore, the role of routine screening among higher-risk individuals cannot be overstated.
Who Needs to Have a Colonoscopy?
- Colorectal Cancer Screening - All above 45-50 years old (Reference MOH guidelines, American Cancer Society guidelines 2018)
- Family history of Colorectal Cancer- to start 10 years before the age of diagnosis of the family member with colorectal cancer (eg family member diagnosed at 50 years old, screening should be done at 40 years old)
- Family history of polyps
- Evaluation of abdominal discomfort
- Evaluation of gastrointestinal bleeding
- Evaluation of anaemia
- Evaluation of change in bowel habits
- Evaluation of unexplained weight loss
How Does a Colonoscopy Work
A colonoscopy is an endoscopic exam used to detect abnormalities or growths in the colon and rectum.
It is made up of a thin, long tube attached to a light source and a small video camera at the end. While the patient is under anaesthesia, the colonoscope is gently inserted into the anus and through the entire colon. As the colonoscope goes through, the images captured are projected on a screen in real-time, allowing the doctor to have a clear look at the walls of the rectum and colon.
Should there be any abnormalities spotted, such as a polyp, the colonoscopy doctor can remove it on the spot, so that it does not progress any further. The polyp is then sent for testing at a lab to see if it contains malignant cells or not.
A Singapore colonoscopy takes around 30 minutes, and the patient should feel no pain during and after the procedure.
Preparing for a Colonoscopy
A colonoscopy is performed under monitored sedation and you will be asleep and comfortable. Often the most difficult part about the colonoscopy is the preparation for the scope. In order for a colonoscopy to be as accurate as possible, the colon must be clear. When taken as prescribed, the laxatives will result in diarrhoea, allowing the patient to fully empty their bowels and to ensure that the colonoscopy is accurate.
We will also recommend that you only consume plain, easily digestible foods (low-residue diet) starting from two to three days before the scheduled colonoscopy. Medications such as antiplatelets or anticoagulants (blood thinners) will be stopped.
Do avoid taking alcohol as this may interact with our sedative medications. Do also stop traditional medicines or some supplements which may cause blood-thinning properties and increase the risk of bleeding during the procedure. Our medical team will advise you prior to the procedure. Please also avoid driving on the day of the procedure.
When a Polyp Removal is Needed
As mentioned above, colonic polyps are usually removed when detected during a colonoscopy, which eliminates the risk of that polyp ever becoming malignant. This procedure is known as a polypectomy, which can be performed very quickly in experienced hands.
Typically, the polyp will be removed using a wire loop, which will either burn off or cut out the polyp. This process is completely painless as there are no nerve endings in the colon that can sense pain, touch or temperature.
The removed polyp will be sent for testing to determine its nature. If malignancy is detected, further treatment may be needed, as advised by your colonoscopy doctor.
After a Colonoscopy
While you should not feel any pain, you may experience some bloating, gassiness or light cramping for a few hours. You may also notice some blood during bowel movements - this is common and will resolve. However, should you experience heavy bleeding, severe stomach pains or a fever, seek medical attention immediately.
What Do the Results of My Colonoscopy Mean?
Colonoscopy results are typically categorised as either positive or negative. Understanding the implications of each result is crucial for managing concerns and guiding subsequent healthcare decisions.
Negative Result
A negative colonoscopy result means no polyps, inflammation, or signs of cancer were found. Your colon looks healthy and normal. However, risks can increase with age or new health issues, so regular screenings are still important. If you are at average risk, your next colonoscopy is usually in 10 years. If you have risk factors like a family history or past polyps, your doctor may recommend screening every 5 years instead.
Positive Result
A positive colonoscopy result means that something unusual was found during the examination. Here are some common findings:
- Polyps - These are growths that develop on the inner lining of the colon. Most are benign, but some have the potential to turn into cancer over time.
- Diverticular Disease - This condition happens when small pouches, called diverticula, form along weak spots in the colon wall.
- Haemorrhoids - These swollen veins near the rectum or anus may bleed or cause discomfort but are typically mild and treatable without surgery.
- Intestinal Ulcers or Sores - Chronic conditions like inflammatory bowel disease or long-term medication use can cause ulcerations in the colon lining, which need further management.
- Tumours or Blockages - Sometimes growths or physical obstructions in the colon are identified.
Are There Any Risks Associated with a Colonoscopy
Although a colonoscopy is a widely performed and generally safe procedure, there are still certain risks that you should be wary of.
- Mild discomfort like bloating or cramping is normal and usually passes within a day or two.
- Minor bleeding may occur, especially after removing polyps or taking a biopsy.
- Colon perforation is rare but often requires treatment.
- Infections are rare due to strict sterilisation protocols.
When To Get A Colonoscopy in Singapore
If you are above 50 years old, you should get a colonoscopy done once every 10 years, provided your results come back normal. If you have a personal or family history of colorectal cancer or polyps, then you should be screened at an earlier age and at a closer frequency.
Your doctor will be best positioned to assess your individual situation and recommend a good screening schedule. Be sure to visit an established colonoscopy centre in Singapore for trusted advice and effective care.
Are There Any Alternatives to Colonoscopy?
Aside from colonoscopy, there are alternative ways to examine and detect colon cancer and precancerous polyps. These methods may be considered in certain situations based on patient preferences, health conditions, or risk factors.
Barium Enema
A barium enema is an older diagnostic method that uses X-ray imaging to visualise the colon. During this procedure, a small tube is inserted into the anus and fills the colon with a white, chalky solution called barium. The barium coats the colon walls, making them stand out on X-ray images.
Although barium enema can identify blockages, strictures, or large growths, it is less sensitive than colonoscopy for detecting smaller polyps or flat lesions.
CT Colonography
CT colonography, often called a virtual colonoscopy, uses advanced CT scans to create detailed pictures of the colon and rectum. The patient then undergoes scans in different positions, such as lying on their back and stomach, to capture comprehensive images. Computer software reconstructs a three-dimensional view of the colon.
Unlike traditional colonoscopy, CT colonography does not involve inserting a long scope throughout the entire colon, and sedation is generally unnecessary. Although it is less invasive, any suspicious growths found during CT colonography will still require a follow-up colonoscopy for removal or biopsy.
FAQ on Colonoscopy
How much does a colonoscopy cost in Singapore?
Can I eat immediately after a colonoscopy?
Is the colonoscopy procedure painful?
Helpful Links
Our Colonoscopy Doctor
Dr Chew Min Hoe
Medical Director
Senior Consultant, General & Colorectal Surgeon
MBBS (Singapore), MRCS (Edinburgh), MMed (Surgery), FRCS (Edinburgh)
Dr Chew Min Hoe is a highly experienced General and Colorectal Surgeon in Singapore. With over 20 years in the public sector, his broad expertise includes significant proficiency in colonoscopy for screening and diagnosis. Dr Chew holds advanced training in complex pelvic surgery and is committed to providing thorough and accurate colonoscopies.
Our Motto
Caring Hearts, Educated Minds, Skilled Hands
Orchard
3 Mount Elizabeth #16-09, Mount Elizabeth Medical Centre,Singapore 228510
Tel:+65 6518 4688
Fax:+65 6235 0897
Mon-Fri:8:30am - 5:30pm
Sat / PH Eve:8:30am - 12:00 noon
Sun & Public Holiday: Closed
Farrer Park
1 Farrer Park Station Road Connexion,#08-07 Farrer Park Medical Centre,Singapore 217562
Tel:+65 6518 4868
Fax:+65 6443 6616
Mon-Fri:8:30am - 5:30pm
Sat / PH Eve:8:30am - 12:00 noon
Sun & Public Holiday: Closed
