Common GI Conditions

Colorectal Cancer (CRC): What Do I Need To Know?

What is CRC?

Colorectal cancer is cancer that is developed from the large intestine. The large intestine is responsible for absorption of water and storage of faeces. The cells in the large intestine can transform into cancer from any part. If this occurs in the colon, it is called colon cancer and if it occurs in the rectum, then it is called rectal cancer.

How common is CRC & How does it start?

CRC tops the ten most frequent cancers affecting men and women in Singapore. According to the cancer society of Singapore, the frequency of CRC is 17% in men and 13% in women. It is one of the top 5 causes of cancer-related death in Singapore. CRC begins as a small growth from the inner lining of the large intestine. These growths are called polyps. Over time these polyps, if not identified and treated, can increase in size and transform into cancer.

What causes CRC? 

Several risk factors have been identified to be associated with the development of colorectal cancer. These include:

What is CRC?

What are the symptoms of CRC?

Several risk factors have been identified to be associated with the development of colorectal cancer. These include:

The signs and symptoms of CRC include:

a) Change in bowel habits (persistent diarrhoea or constipation)
b) Passage of blood in stools
c) Unintended weight loss
d) Abdominal pain or discomfort

How to diagnose colorectal polyps and cancer early?

It is important to detect polyps and cancer early. The good news is early detection and treatment of polyps/cancer can prevent progression and result in cure. This can be achieved by screening at regular intervals.Screening refers to the process of identifying polyps or cancer at an early stage before.

Screening refers to the process of identifying polyps or cancer at an early stage before development of symptoms.

What are the screening tests for CRC?

The screening tests for CRC include:

a) Guaiac-based faecal occult blood test (g-FOBT)
b) Fecal immunohistochemical test (FIT)
c) Sigmoidoscopy
d) Colonoscopy
e) CT colonography

Colonoscopy and CT colonography have increased yield in detecting polyps and cancer. Hence, these tests would be preferred when available.

When should you start screening?

In Singapore, CRC screening is recommended for men and women over the age of 50.  People at higher risk, such as those with a family history of CRC, would benefit from screening at a younger age.

Further details regarding CRC screening can be obtained from your General Practioner.

You can access:

https://www.hpb.gov.sg/HOPPortal/dandc-article/598  or

http://www.singaporecancersociety.org.sg/events/campaigns/colorectal-cancer-campaign.html  for more information.

What is the treatment of CRC once detected?

The treatment of CRC is based on the stage of cancer. The depth of intestinal wall involvement; the spread to nearby structures; and involvement of lymph nodes and other organs determine the staging of CRC. The current treatment options include :

a) Endoscopic removal of polyps and early cancer
b) Surgery
c) Chemotherapy and
d) Radiotherapy

What is the survival rate of colorectal cancer?

The survival rates of CRC are determined by the stage of cancer, patient factors and response to therapy. Treatment strategies may differ from patient to patient. Hence, contact your doctor for more information

“An ounce of prevention is worth a pound of cure” 

The best preventive strategy for colorectal cancer is to adopt a healthy lifestyle and enrol in a regular screening program.