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Colorectal Cancer

In Hong Kong , there are over 5000 new cases of colorectal cancer every year. Colorectal cancer is the most common cancer and it ranks number two amongst the cancer deaths in Hong Kong . Data show that the incidence of colorectal cancer is on an uprising trend.

Risk Factors

1. Unhealthy lifestyle

  • excessive saturated fat intake
  • low fibre intake
  • frequent intake of grilled or barbecued food
  • smoking and alcoholism
  • lack of exercise

2. Past history

  • history of colon polyps or ulcerative colitis

3. Family history

  • close relative diagnosed with colorectal cancer or hereditary bowel diseases (e.g. familial adenomatous polyposis)

Signs and Symptoms

  • sudden change in bowel habit, such as diarrhea, constipation or alternating
  • feeling that the bowel does not empty completely after defecation (tenesmus)
  • blood or mucus in stool
  • abdominal discomfort such as abdominal pain, distension or cramps
  • abdominal mass or enlargement of lymph node above the clavicle
  • if intestinal obstruction occurs, there will be constipation, abdominal pain and vomiting

In late case, the patients may have anaemia, unexplained weight loss or malaise.


  • Surgery
    Surgery is the main treatment of colorectal cancer. If the tumour is close to the anus, a hole or an artificial anus (colostomy) may need to be made on the abdomen for excretion of stool after excision of the anus together with the tumour.
  • Chemotherapy
    Chemotherapy is an adjuvant therapy to control the spread of cancer.
  • Radiotherapy
    Radiotherapy is also an adjuvant therapy to kill the cancer cells by special high energy X-rays.
  • Psychological Support
    Patients may suffer from the negative feeling of anger, depression or helplessness. Support from family members and medical staff are very important. They should know more about the disease, choice of treatment and rehabilitation care so as to help the patient to cope with the disease

Prevention of Colorectal Cancer

1. High fibre diet

  • intake of high fibre food such as cereals, whole wheat bread, different kinds of green vegetables and fruits, beans and nuts
  • diets high in a variety of vegetables and fruits which contain antioxidants to help reduce the risk of colorectal cancer

2. Low fat diet

  • avoid excessive intake of fat especially saturated fat like animal fat, coconut oil and palm oil
  • avoid excessive intake of red meat, take about 4-6 tales meat daily
  • avoid preserved or smoked foods such as sausage
  • trim off visible fat from meat and remove the skin of poultry before cooking
  • use low-fat cooking methods such as steaming, blanching, braising, and baking
  • use unsaturated vegetable oil such as peanut oil, canola oil and olive oil, total amount of cooking oil per day is about 2 tablespoons

3. No smoking and avoid excessive intake of alcohol

4. Exercise regularly

  • Regular exercise promotes bowel movement and helps to reduce the risk of colorectal cancer. It also helps to maintain an optimal body weight. Exercises s uch as walking, swimming and playing ball games for at least 30 minutes daily are beneficial to health. Choose the right exercise that meets your ability and interest. Never exceed your body limit. Always put safety first to prevent falls and accidents.

5. Regular check-up

  • According to the health advice in "Recommendations of the Cancer Expert Working Group (CEWG) on Cancer Prevention and Screening" of Colorectal Cancer Screening Pilot Programme, Department of Health, people with family history of colorectal cancer should take check-up at younger age. For more information about Colorectal Cancer Screening Pilot Programme, please visit:
  • Everyone should look out for signs and symptoms of colorectal cancer such as change of bowel habit, unexplained persistent blood or mucus in the stools and tenesmus. Consult your doctor as soon as possible. Colorectal cancer can be successfully treated, particularly if diagnosed in early stage.