Blog Details Image

What is colorectal cancer, and how can you detect it?

Colorectal cancer is a health challenge, often eluding early detection until it advances to critical stages. Affecting the colon and rectum, integral parts of the digestive system, this cancer can be lethal. 

This article aims to demystify colorectal cancer, delving into its development and highlighting various detection methods. By learning more about the disease, you can make informed choices and take protective measures against it.

What is colorectal cancer?

According to the National University Cancer Institute Singapore (NCIS), colorectal cancer is a top killer, affecting more than 1865 cases each year. Colorectal cancer is the most common cancer in Singapore for men and women combined. 

Most colorectal cancers start with an abnormal growth called a polyp. Likened to the “polyps” that carpet a coral reef from which the name is derived.

How polyps develop into colorectal cancer

Polyps form because of instability in the growth of cells in the large intestinal lining. Cells in the layer are constantly replaced every few days, and with the rapidity of multiplication comes the possibility of genetic errors. 

As more and more genetic abnormalities take place, so too does the chance that polyps will change into cancerous colorectal growths. This is called the “adenoma-carcinoma sequence.” The factors that lead to this instability are debatable, but epidemiological studies show high fat, red meat, and low fibre diets have a role to play.

How polyps develop into colorectal cancer
How polyps develop into colorectal cancer

Who is at risk for colorectal cancer?

While colorectal cancer can affect anyone, certain factors may increase the likelihood of its occurrence. Here are some key risk factors:

Age: Colorectal cancer is more common in older adults, with the risk increasing significantly after the age of 50. The majority of cases occur in individuals over the age of 50, although cases can occur in younger individuals as well.

Family history: Individuals with a first-degree relative (parent, sibling, or child) who has had colorectal cancer are at a higher risk. The risk is even greater if multiple family members are affected or if the diagnosis occurred at a younger age.

Personal history of polyps or colorectal cancer: If an individual has previously had colorectal polyps or colorectal cancer, their risk of developing new polyps or cancer is higher.

Inflammatory Bowel Diseases (IBD): Chronic inflammatory conditions of the colon, such as ulcerative colitis or Crohn's disease, increase the risk of colorectal cancer over time.

Inherited genetic syndromes: Certain genetic conditions, such as familial adenomatous polyposis (FAP) and Lynch syndrome, are associated with a higher risk of colorectal cancer.

Diet and lifestyle factors: A diet high in red and processed meats, low in fibre, and lacking in fruits and vegetables may contribute to an increased risk. Lack of physical activity, obesity, smoking, and excessive alcohol consumption are also associated with a higher risk.

Diabetes: Individuals with type 2 diabetes may have an increased risk of colorectal cancer.

How to detect colorectal cancer?

The key to a cure is early detection through the discovery of polyps, which are considered precursors or early stages of colorectal cancer. Not all polyps become cancerous, but some have the potential to transform into cancer over time. 

Removing precancerous polyps can prevent them from progressing to colorectal cancer. Furthermore, colorectal cancer is more treatable and has a better prognosis when detected at an early stage. By identifying and removing polyps before they become cancerous, the likelihood of successful treatment and a positive outcome increases.

Polyps usually do not give rise to any symptoms unless they are very large, so early screening is paramount.

There are three ways to detect colon polyps:

1. Faecal immunochemical test (FIT) 

2. CT Colonography 

3. Colonoscopy

Faecal Immunochemical Test (FIT)

This test detects microscopic blood in the stool. The test kit consists of a spike to collect a small specimen mixed with the reagent in the bottle. The entire kit is sent to the laboratory for analysis. 

A positive test will require a colonoscopy to detect and remove polyps and rule out cancer. Some inflammatory conditions can also result in a positive test.Multiple samples increase accuracy, and the test is best repeated yearly after age 50.

Faecal Immunochemical Test (FIT)

CT Colonography

This test is a special CT scan that insufflates air into the colon, followed by a non-contrast CT scan. The computer then reconstructs the images into a “virtual” image of the colon showing any polyps. Bowel preparation is required. If a polyp is detected, then a colonoscopy is required for polypectomy.

CT Colonography


A colonoscopy allows your colorectal doctor to inspect the inside of the colon and rectum using a soft, tube-like instrument called a colonoscope. This procedure is valuable for detecting and preventing colorectal cancer. It is considered one of the most accurate methods for detecting colorectal abnormalities. It allows for a detailed examination of the entire colon, providing a comprehensive assessment of intestinal health.

Colonoscopy can detect and remove polyps and identify early-stage colorectal cancers. Early detection provides better protection against cancer, as it allows intervention before the cancer advances to more difficult-to-treat stages.


Polyps detected during the colonoscopy procedure will be removed through a polypectomy. Depending on the size of the polyp, different methods can be used. A special lasso knife that can be passed through the biopsy channel of the colonoscope is used to loop over the polyp to snip it off the lining of the intestine. Electro-cautery can stop bleeding after polypectomy or clips to close the subsequent defect.


Finding a colorectal specialist in Singapore

Selecting a colorectal doctor is an important decision. Here are some key considerations when choosing a colorectal specialist in Singapore.

Reputation and testimonials

  • Research the specialist's reputation by reading testimonials from previous patients.
  • Check online platforms, healthcare review sites, and social media for feedback on the clinic's services.

Expertise and accreditation

  • Look for surgeons who are board-certified, have relevant experience, and specialise in colorectal procedures.
  • Check if the clinic and its surgeons have relevant accreditations and certifications from recognised healthcare organisations.
  • Accreditation ensures that the surgeons adhere to high standards of patient care and safety.

Services and facilities

  • Ensure that the specialist offers a full range of colorectal services, including diagnostic procedures, surgeries, and post-operative care.
  • The clinic should have the necessary facilities and equipment for colorectal examinations and treatments.

Patient-centric Approach

  • Look for a doctor that prioritises patient satisfaction and provides clear communication throughout the colorectal treatment process.
  • Assess the level of patient care, including the responsiveness of the staff to inquiries and the overall patient experience.

Referral process and collaborations

  • Check if the doctor has established collaborations with other healthcare providers and specialists for comprehensive care.
  • Understand the referral process if you need to consult with other medical professionals.

Before making a decision, schedule consultations with potential clinics, meet with colorectal doctors, and ask questions to ensure that the specialist aligns with your needs and preferences.

Questions to ask a colorectal surgeon

Asking questions during a consultation with your colorectal surgeon is important for several reasons. Clear communication helps you understand your condition, the proposed treatment plan, and what to expect during and after surgery. Here are some questions you should ask.

  • What is my diagnosis, and how does it affect me?
  • What are the treatment options available for my condition?
  • What is the recommended treatment plan, and why is it the best option for me?
  • What are the risks and complications associated with the surgery?
  • Have you performed the specific procedure I need, and how frequently do you perform it?
  • What is your success rate with this procedure, and what are the potential complications?
  • What is the expected outcome of the surgery, and what is the success rate?
  • What is the expected recovery process, and how do you support patients during the postoperative period?
  • How do you handle complications or unexpected challenges during surgery?

Asking these questions fosters a collaborative and informed healthcare partnership between you and your surgeon. It empowers you to actively participate in decisions about your treatment, enhances your understanding of the medical process, and contributes to better overall outcomes. Your colorectal surgeon is there to provide you with the information you need to make the best decisions for your health.

Colorectal doctor in Singapore

Understanding colorectal cancer and embracing early detection strategies are pivotal steps in safeguarding your health. By familiarising yourself with the screening methods outlined in this article, you can take proactive measures against this silent threat. If you or someone you know has colorectal issues, consider a colorectal screening with a specialist. 

The Colorectal Clinic is dedicated to providing specialised care for colorectal conditions in Singapore. Our experienced and skilled colorectal doctors form the backbone of The Colorectal Clinic.  

Schedule an appointment with us for an evaluation.

No items found.



No items found.

Other Posts

Blog Thumbnail Image

Endoscopy Applications

Massive lower gastro-intestinal bleeding can be managed 90% of the time non surgically through a combination of therapeutic...

Calendar Image
Blog Thumbnail Image

Common Digestive Disorders

Discover some of the most common digestive complaints.Pain during passage of stool, an abnormal lump or blood stained discharge may be...

Calendar Image


No items found.
Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.