Colorectal Cancer Screening

What is a colorectal cancer screening?

Colorectal cancer is the most common cancer in Singapore. Early stage colorectal cancer may not have any symptoms. Early detection can greatly increase the chances for a successful treatment.

At Mount Elizabeth Medical Centre, our specialists in gastroenterology may provide screenings with a gastroscopy, a colonoscopy, or a combination of both to help you detect early signs of colorectal cancer. A gastroscopy is a procedure where the oesophagus, stomach, and part of the small intestine are inspected using an endoscope, which is a thin and flexible tube with a light and camera. A colonoscopy is a procedure which involves the use of an instrument to examine the inside of the colon.

Screenings may also include testing for blood in a stool sample.

When or how often should I get a colorectal cancer screening?

The Singapore Health Promotion Board recommends two options to screen for colorectal cancer for those aged 50 years and older, the Faecal Immunochemical Test (FIT) every year or a screening colonoscopy once every 10 years.

Did you know?

Between 2011 and 2015, Singapore Chinese men and women were more likely to develop colorectal cancer compared to their Malay and Indian counterparts. Men were also more likely to develop colorectal cancer compared to their similarly aged female counterparts¹.

What are the risks of a colorectal cancer screening?

A colonoscopy is generally a safe procedure. Very rarely, the following complications may occur:

● excessive bleeding from where a tissue sample or polyp was taken or removed
● adverse reaction to the sedative used during the colonoscopy
● a tear in the colon or rectum wall (perforation)

How should I prepare for my colonoscopy?

Prior to the colonoscopy, you will be asked to empty your colon as any residue may obscure the view of your colon or rectum. To do this, your doctor will likely ask you to do the following the night before the examination:

● consume a diet of clear liquids with no solid foods
● take a laxative
● adjust or stop your medications

You are advised to tell your doctor if you are currently taking any blood thinners or anti-coagulants.

What can I expect during a colorectal cancer screening?

Just before the procedure begins, you will be given a sedative, either in a pill form or combined with an intravenous pain medication to minimize discomfort.

You will be asked to lie on your side with your knees drawn up. The doctor will insert the colonoscope into your rectum. The scope contains a light, video camera, and a channel for the doctor to pump air. The video camera sends images to an external monitor, allowing the doctor to see the lining. Inflating the colon allows the doctor to better see the lining.

As the scope moves or is being inflated, you may feel some cramping or an urge to pass a bowel movement. The channel also allows the doctor access to insert devices to take tissue samples or remove polyps.

A colonoscopy will likely take about 20 minutes to an hour.

What happens after my colorectal cancer screening?

After the colonoscopy, you will likely need about an hour to recover from the sedative and be allowed home.

You may feel uncomfortable for a few hours after the exam with the air that was pumped in during the procedure. You may feel bloated or be passing gas for a few hours. Walking may help to alleviate discomfort.

A small amount of blood may be present in your first bowel movement after the colonoscopy. This is not a cause for alarm. However, if you have any signs of a fever, persistent pain in the abdomen, or continue to pass blood or blood clots, contact your doctor.

[1] National Registry of Diseases. Singapore Cancer Registry Annual Registry Report 2015. 2017. Accessed November 29, 2017.