Colorectal Cancer

Colorectal cancer is a disease affecting the colon and rectum in which cells in either organ grow out of control. Sometimes it is called colon cancer, for short.

Colorectal cancer is the most prevalent cancer in Malaysian men (affecting about 15 in 100,000 people) and the second most common cancer in Malaysian women (affecting 11.1 in 100,000 people). It is also Malaysia's third leading cause of cancer deaths.

There are several factors involved but the ultimate changes occur in the deoxyribonucleic acid (DNA) of our cells. DNA changes or mutations can cause cells to grow out of control and the expression or suppression of certain genes can lead to tumour formation.

• Old age (over 50 years of age)
• Presence of polyps in the large intestine
• Family history of colorectal cancer: You are more likely to develop colon cancer if you have a blood relative who has the disease
• Smoker: Smokers have an increased risk of colon cancer. Stop smoking to lower your risk of colon cancer
• Previous cancer e.g. colorectal cancer
• Have ulcerative colitis or Crohn's disease (inflammation of the colon)
• Unhealthy diet high in fats, red meat and processed food, and low in fruits and vegetables (fibres): People with low consumption of fibres have an increased risk of colon cancer
• Obesity

Early-stage colorectal cancer is likely to be symptom-free and can be identified through active screening for colorectal cancer.

Some signs and symptoms of colorectal cancer are:

• Blood in the stool
• Change in bowel pattern (diarrhoea or constipation)
• Unintentional weight loss
• Abdominal pain
• Vomiting
• Feeling that your bowel does not empty thoroughly
• Feeling fatigue
• Frequently having gas pains or cramps, feeling full or bloated

• Colonoscopy
• Biopsy
• Imaging tests: x-rays, computed tomography (CT) scans, magnetic resonance imaging (MRI) scan and positron emission tomography (PET) scan
• Blood tests: complete blood count, tumour markers and liver enzymes

Learn more about the different types of screening and diagnostic procedures performed to diagnose colorectal (colon) cancer.

• Surgery - most colorectal cancers will have to be removed with surgery:
• Early stage: Laparoscopic approach (key-hole surgery) or polypectomy (removing polyps during a colonoscopy)
• More advanced stage: Open surgery to remove the cancer and surrounding colon tissues and lymph nodes (glands)
• Chemotherapy
• Depending on the stage of the cancer, the patient may require pre-operative or post-operative chemo-radiotherapy
• Surgery, combined with appropriate chemoradiotherapy, offers more than 90% cure rate in stage one disease. Advance and recurrent colorectal cancer patients may be treated with heated chemotherapy during the operation, a procedure called Hyperthermic Intraperitoneal Chemotherapy
• Radiation therapy (high-energy x-rays)
• Immunotherapy
• Targeted drug therapy

Learn more about the different types of treatment technologies to treat colorectal (colon) cancer.

You can help prevent colorectal cancer by practising the following healthy habits:

• Eat a healthy balanced diet; one that is rich in fibre with an emphasis on fruits and vegetables and whole grains.
• Avoid red meat and processed food and over consumption of charred or barbecued meat.
• Avoid a sedentary lifestyle by exercising regularly. Getting regular physical activity may reduce your risk of colon cancer.
• Abstain from smoking and reduce consumption of alcohol. Stop smoking and limiting the amount of alcohol you drink may reduce your risk of colon cancer.
• Keep a healthy weight.
• Conducting screening tests as necessary.

It is recommended that individuals with an average risk of colon cancer begin colon cancer screening around the age of 45. However, people who are at a higher risk e.g. those who have a family history of colon cancer, should consider screening earlier.

Screening tests can detect precancerous polyps, allowing them to be removed before they develop into cancer. Colorectal cancer screening tests can also detect the cancer early, when therapy is most effective.

Colonoscopy

Colonoscopy is a very effective procedure in screening, diagnosing and preventing colorectal cancer. The procedure is performed under sedation and involves the doctor examining the entire colon.

If precancerous polyps are found, they can be removed during the colonoscopy thus preventing them from developing into cancer.

Immunochemical faecal occult blood test (iFOBT)

Immunochemical faecal occult blood test (iFOBT) is a lab test that can identify blood in stool that are not seen by the naked eye. The stool is collected at home and sent to a lab. Individuals above the age of 50 are encouraged to do iFOBT once a year.