What is Colorectal Cancer?

Colorectal cancer, also referred to as colon cancer, rectal cancer or bowel cancer, is a cancer of the colon and rectum (or large intestine), which is the last part of the gastrointestinal tract. It is the main organ where faeces are stored before expulsion from the body through the anus.


What you need to know about Colorectal Cancer

#1 Cancer in Singapore (Overall)

Each year, about 1,500 Singaporeans are diagnosed with it and 650 patients die from it (Parkway Cancer Centre, 2017). It is most common in Men and second in Women.

Younger Adults are Increasingly at Risk

Over the last ten years, the number of colorectal cancer patients diagnosed under the age of 50 has doubled from 1-in-10 cases to 1-in-5 ().

It is PREVENTABLE if discovered early

Colorectal cancer usually develops from polyps, which are abnormal tissue growths which may grow in any part of the colon. Precancerous may take up to 10 to 15 years before turning cancerous. As such, they should be removed the moment they are detected.

How does Colorectal Cancer develop?

Polyps are the Common Starting Ground 

According to Associate Professor Tang Choong Leong, Head and Senior Consultant from the Department of Colorectal Surgery, Singapore General Hospital (SGH): 

“Most types of colorectal cancer arise from polyps which start out as benign or non-cancerous growths from the cells lining the inside of the colon or rectum. The change from being benign to becoming cancerous may take years but once a polyp becomes cancerous, it can grow and invade surrounding organs."

A polyp can take up to 10 to 15 years to develop into cancer, but these polyps may be found and removed before they have the chance to turn into cancer when one undergoes screening (Healthline Editorial Team & Chun, 2019; Singapore General Hospital, 2018).

Survival Rates Decrease In Later Stages of Cancer

In Stage I of the disease, the cure rate is greater than 90%In the later Stages III and IV, the average five-year survival rates are 40%-60% and 10% respectively. Hence, early detection is of paramount importance. 

(Chumari, n.d.).

3 Common Signs & Symptoms

Do note that this is not an exhaustive list. However, these are common symptoms observed in patients suspected with colorectal cancer. If you do experience any of said symptoms, make sure to consult a medical professional and not ASSume the nature of its cause.


Blood in Stools

Presence of blood in stools can manifest as either fresh blood (which appear as red streaks in stools) or dried blood (stools appearing darkish red and sometimes even black). If you notice any of these, you should see a doctor for evaluation immediately.

Among patients who have rectal bleeding, 2-3% can be attributed to colorectal cancer, and 20-30% are also likely to have precancerous polyps which should be removed to prevent future development into cancer.

Persistent Urge to Pass Motion

Also medically referred to as 'Tenesmus', this sensation refers to a persistent feeling of needing to pass motion even if there is nothing to dispel. This sensation may also be accompanied by abdominal discomfort such as cramps, gas or pain.

While experiencing tenesmus, you may feel the need to strain harder to produce only a small fraction of stools during bowel movement. In certain cases, it may also feel as if there's stools stuck in your rectum.

Persistent Change in Bowel Habits

You may experience a sudden increase or
decrease of bowel movements, or even
physical changes to your stools that are
unusual (i.e. mucus in stools, thinner stools, persistent constipation or loose stools).


If such symptoms persist over a period of time, it would be best to get it checked with a doctor. Persistence need not be an everyday occurrence, as long as it recurs over an unusual duration of time.

Experience any of the above symptoms?

Best to get ASSured and consult a medical professional.

Dr. Wong Nan Yaw, Colorectal Specialist

Mount Elizabeth Medical Centre

"Young people frequently dismiss their symptoms to something benign like hemorrhoids or indigestion. They tend not to seek medical attention. Thus, the cancer often presents late and at an advance stage."

Are you at Risk?

While there is no one exact cause for colorectal cancer, there are various factors – including your lifestyle choices, that can contribute to your chances of developing colorectal cancer. 

Read on to find out if you're at risk.


Uncontrollable Risk Factors


Risk of developing colorectal cancer increases sharply with age, especially after the age of 50. 


Males have a slightly higher risk of getting colorectal cancer compared to Females, with a ratio of 1.2:1.


Chinese have a higher risk of developing colorectal cancer as compared to their Malayand Indian counterparts.

Family History

Individuals with relatives (especially first-degree) who have had colorectal cancer before are at a higher risk of developing colorectal cancer.

Personal Medical History

If you have a history of bowel-related diseases such as inflammatory bowel disease, you are at a higher risk.

Genetic Syndrome

If you have a history of bowel-related diseases such as inflammatory bowel disease, you are at a higher risk.

Individuals with relatives (especially first-degree) who have had colorectal cancer before are at a higher risk of developing colorectal cancer.

Controllable Risk Factors

Sedentary Lifestyle

The lack of an active lifestyle coupled with a higher BMI are contributors to overall colorectal cancer risk.

Low Fibre & High Fat Diet

Research has shown that there is a correlation between colorectal cancer and unhealthy diets that are high in red and processed meats, lacking fibre.


While more commonly associated with lung cancer, smokers are also at a higher risk of developing colorectal cancer as
compared to non-smokers.

High Alcohol Consumption

Guidelines as written by Dr. Jit Fong Lim in his article here, suggests limiting yourself to two alcoholic drinks a day.

"Make changes to your lifestyle in the above areas to reduce your risk today!"

Types of Screening Methods

As colorectal cancer symptoms may not always present itself in the earlier stages, screening is still important in helping detect precancerous polyps. Currently in Singapore, there are a total of five different screening methods available to select from.


FIT (Faecal Immunochemical Test) Kit

Rectal bleeding may not always be visible to the naked eye, as such the FIT kit is a preliminary test useful for detecting small traces of blood in faeces. However, it is impossible to draw any complete conclusions about the presence of polyps through this test and a further colonoscopy may be suggested upon positive detection of blood.

Singapore Cancer Society (SCS), distributes these FIT kits, free of charge, to eligible Singaporeans and Permanent Residents above the age of 50.


Click here to find out more.

Flexible Sigmoidoscopy

This procedure evaluates the rectum and the sigmoid (lower) colon for polyps, abnormal areas or cancer. A flexible, tiny tube-like instrument with a light and a video camera is inserted through the rectum into the sigmoid colon for examination.


However, sigmoidoscopy does not allow the inspection of the entire colon. As such, polyps further into the colon may be missed out.


Regarded as the gold standard for screening, colonoscopy is the most accurate test in checking for colorectal cancer. In addition, the procedure also allows for the surgeon to detect and remove pre-cancerous polyps if detected, thus stopping it from developing into something potentially cancerous.

With the ability to remove pre-cancerous polyps, colonoscopy is the only method to date that can effectively prevent colorectal cancer if done early. 

CT Scan / Colonography

A minimally invasive imaging examination of the colon and rectum. It uses X-rays to acquire images and a computing technological software to digitally process 3D images of the colon for interpretation. 

Barium Enema

A specialised X-ray examination of the colon and rectum. This screening procedure requires the introduction of a barium-based liquid (similar to a dye) into the rectum through a narrow tube. This dye then coats the length of the intestine to produce clear X-ray images of the colon. 

Looking for Financial Assistance?

Here are some helpful links for you. 

Singapore Cancer Society

  • Cancer Care Fund

  • Welfare Aid Fund

  • Cancer Treatment Fund

  • Education Financial Assistance Scheme 


Read more about their funds here.

National Cancer ​Centre Singapore

National Cancer Institute of Singapore


" Don't Be a Fool, Check Your Poo "

© 2020 by Don't Assume, Be Assured.