Colorectal Cancer

Colorectal cancer is the number 1 cancer in Singapore. Screening tests such the Faecal Immunochemical Test (FIT) and screening colonoscopy can help prevent colorectal cancer


What is Colorectal Cancer?

Colorectal cancer is cancer of the large intestine (colon and rectum). Most cases of colorectal cancer begin as small, non-cancerous growths attached to the wall of the colon. These growths are called polyps and may become cancerous over time.



In the early stages, people with colorectal cancer may not experience any symptoms.

In the later stages, the common signs and symptom​s include:

  • A change in bowel habits, including diarrhoea or constipation
  • Presence of blood in the stool
  • Persistent abdominal discomfort such as cramps, gas or pain

Related: Signs and Symptoms of Colorectal Cancer​​​​


Screening for colorectal cancer should begin from age 50 for people with no symptoms. The recommended screening tests are:


​The FIT is a test that:

    • Detects the presence of small amounts of blood (that can't be seen with the naked eye) in the stools.
    • Is safe, quick and easy to do, and can be done at home, without the need to change your diet before the test.
    • Should be done once a year

You can go for colorectal cancer screening (using FIT) through the HPB's Integrated Screening programme. In this programme, you will be given two FIT kits because two stool samples should be collected over two days for a more accurate result.

Screening using FIT should be done once a year. However, if you develop signs or symptoms even after a normal FIT result, please see your doctor immediately.


The screening colonoscopy:

  • Uses a flexible tube (colonoscope) to look at the inner lining of the large intestine (colon and rectum).
  • Takes about 20 to 30 minutes to complete
  • Has to be done in a hospital by a doctor trained in conducting colonoscopies
  • Should be done once every 10 years

Discuss with your doctor which screening test is best for you.

Related: Screen for Life


The three main treatment options for colorectal cancer are surgery, chemotherapy and radiation. These options which may be used alone or in a combination.


Surgery involves removal of the part of the colon that contains the cancer cells.


Chemotherapy can be used to destroy cancer cells after surgery, to control tumour growth or to relieve symptoms of colorectal cancer. Possible side effects of chemotherapy include:

  • ​​Nausea and vomiting​
  • Mouth sores
  • Fatigue
  • Hair loss and diarrhoea

Radiation therapy

Radiation therapy uses X-rays to kill any cancer cells that might remain after surgery, to shrink large tumours before an operation so that they can be removed more easily, or to relieve symptoms of colorectal cancer. Side effects of radiation therapy may include:  
  • ​​​​​​Diarrhoea
  • Rectal bleeding
  • ​Fatigue


You can take steps to reduce your risk of colorectal cancer by:

  • ​​​​Eating plenty of fruits, vegetables and wholegrains which contain fibre and antioxidants
  • Limiting fat especially saturated fat from animal sources such as red meat, milk, cheese and ice cream. Plant-based "vegetable oil" can also be high in saturated fat
  • Limiting alcohol intake
  • Quitting smoking
  • Staying physically active and maintaining a healthy body weight

For more information about your recommended screenings, visit and FAQs on Screen for Life

Read these next:



​A person with myopia, or shortsightedness can see near objects clearly but distant objects appear blurred. This is because the focal point of a visual image falls in front of the retina instead of directly on it. The eyeball may be too long from front to back.

Health Promotion Board

Share on Facebook now for

Common Childhood Illnesses — Asthma
Common Childhood Illnesses — Asthma

When your child needs to breathe hard

Health Promotion Board

Share on Facebook now for

Stroke: Impact of Stroke
Stroke: Impact of Stroke

The physical and emotional conditions after a stroke.

Stroke Services Improvement Team

Share on Facebook now for

More A-Z

Colorectal Cancer

 Catalog-Item Reuse

Back to Top