Colorectal Cancer

What is Colorectal Cancer?

Colorectal cancer is a cancer that develops in the colon or the rectum. These cancers can also be named colon cancer or rectal cancer, depending on where they start.

Note: Colon cancer and rectal cancer are often grouped together because they have many features in common.



Hong Kong

Hong Kong

Incidence rate: 35 per 100,000 populations (male & female)

Mortality rate: 12.2  per 100,000 populations (male & female)

(Hong Kong Cancer Registry 2020)



Incidence rate: 4.3  per 100,000 populations (male & female)

Mortality rate: 2.5 per 100,000 populations (male & female)

(IARC, 2021)



Incidence rate: 5.3 per 100,000 populations (male & female)

Mortality rate: 3.0 per 100,000 populations ((male & female)

(IARC, 2021)



Incidence rate: 4.8 per 100,000 populations (male & female)

Mortality rate: 2.8  per 100,000 populations (male & female)

(IARC, 2021)


Early stage colorectal cancer may not have any symptoms.

  • Blood mixed with feces.
  • Mucus in the feces.
  • Change in bowel habit (e.g. Passing stool more often than usual, diarrhea alternating with constipation).
  • Bloating (stomach feeling full of gas or fluid, that is unpleasant).
  • Abdominal (Tummy) pains.
  • Generally unwell, tiredness and weight loss.

Risk Factors

Modifiable: Mainly related to sedentary lifestyle

  • High consumption of red meat and processed meat
  • Lack of physical activity
  • Being obese
  • Excessive alcohol consumption
  • Smoking


  • Men aged 50 or above
  • History of colonic polyps
  • Family history of colorectal cancer
    • If your parent, sibling, or children has colorectal cancer, risk of developing the disease increases 2-3 folds.

  • Hereditary bowel diseases
  • Prolonged history of inflammation of the bowel

Please note: Having above risk factor does not mean that you must have colorectal cancer – it only means that your risk of developing colorectal cancer may be higher than average and you should seek further medical advice from your doctor.

Preventive Measures

  • Eat high fiber diet such as, vegetables, fruits, whole grain, etc
  • Reduce consumption of red meat
  • Do regular exercise (30 minutes every day)
  • Maintain a healthy body weight
  • Reduce alcohol intake
  • Do not smoke