Colorectal Cancer | Oncology| Pantai Hospitals

Colorectal cancer develops when an abnormal mass of cells develops in the colon or rectum. It is also known as colon cancer.

Colorectal cancer is the most common cancer among Malaysian men, inflicting about 15 in 100,000 men, and the second most common cancer among Malaysian women, inflicting about 11 in 100,000 women. It is also Malaysia's third leading cause of cancer deaths.

What causes colorectal (colon) cancer?

In most cases, colorectal cancer develops due to changes in the deoxyribonucleic acid (DNA) make-up of small growths (polyps) in the large intestine. These DNA mutations, combined with the failure of genes to discard mutated cells, will result in uncontrolled division and proliferation, and lead to tumour formation.

What are the risk factors of developing colorectal (colon) cancer?

The development of colorectal cancer is influenced by a complex interplay between a person’s genetic and environmental risk factors. Some common risk factors are:

Age above 50 years old

The risk of developing this cancer is markedly increased after 50 years old. However, apart from the inheritance form of this condition, the onset of colorectal cancer below the age of fifty has become more common over the decade.

Have ulcerative colitis or Crohn's disease (inflammation of the colon)

Having these underlying inflammatory bowel diseases (IBDs) increases the chance of developing this cancer. Chronic inflammation found in IBDs often produces an abnormal cell growth known as dysplasia.

Although dysplastic cells are not yet malignant, they have more chances of developing into a tumour. This risk increases a person’s overall carrier-span of the disease, as well as the level of severity of their inflammation.

Family history of colorectal cancer

Risk of colorectal cancer is increased if one has a blood relative with the disease. Those with two or more cancer-stricken first-degree relatives (parents or siblings) have a greater risk (two to threefold) of the disease, a group which accounts for about 20% of all cases.

A positive family history of colorectal cancer, especially in relatives under the age of 50 at point of diagnosis, confer an increased risk by way of inherited mutations and/or the environment.

Inherited conditions

About 5 in 100 people with colorectal cancer have a genetic condition that predisposes them to acquiring the disease, either in the form of familial adenomatous polyposis (FAP) or hereditary nonpolyposis colorectal cancer (HNPCC, or Lynch syndrome). These two are known to cause cancer at much younger ages. For those with these syndromes, cancer almost always occurs and makes up 1% of all cases.

Other risk factors

Male gender: Both global and local data show higher incidence in males compared to females
Having a diet high in fats, red meat, and processed food, and low in fruits and vegetables (fibres): Low consumption of fibre increases risk of colon cancer
Smoking: Quitting smoking can lower one's risk of colon cancer
Heavy alcohol consumption: More than one drink a day increases risk of colon cancer
Lack of exercise and obesity: Approximately 10% of cases are linked to insufficient activity

What are the signs and symptoms of colorectal (colon) cancer?

Early-stage colorectal cancer may not show obvious symptoms and is identified through active screening for colorectal cancer.

Some signs and symptoms of colorectal cancer are:

Blood in stools
Change in bowel pattern (diarrhoea or constipation)
Change in stool consistency
Unintentional weight loss
Abdominal pain
Vomiting
Feeling that the bowel does not empty thoroughly after a bowel movement
Fatigue
Frequently having gas pains or cramps
Feeling full or bloated

How do doctors diagnose colorectal (colon) cancer?

Different diagnostic tests are chosen by the doctors based on the type of cancer suspected, the age and general health of the person, signs and symptoms, results from earlier medical reports, and family medical history.

Common diagnostic tools include:

Faecal Occult Blood Test (FOBT)
Blood tests: Complete blood count, tumour markers and liver enzymes
Colonoscopy
Biopsy
Imaging tests: Computed tomography (CT) scan, magnetic resonance imaging (MRI) scan, positron emission tomography (PET) scan

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

How is colorectal (colon) cancer treated?

In most cases, colon cancer originates as lumps of cells (known as polyps) within the colon which start turning malignant with time. Doctors can detect the polyps before they turn cancerous.

When cancer has gained substantial size over the years, it is not only able to invade the space of surrounding organs and blood vessels, but penetrate them, allowing the disease to spread.

Oncologists use a staging system to determine the extent of the spread of cancer and to formulate a suitable treatment methodology.

Treatment for colorectal cancer involves a multidisciplinary team approach such as colorectal surgeon, oncologist, radiation oncologist, and gastroenterologist.

Treatment options depend on the type, spread, and size of tumour. Following are the main treatment options adopted:

1. Surgery

Most colorectal cancers will have to be removed with surgery.

For early-stage colorectal cancer: Laparoscopic approach or polypectomy (removing polyps during a colonoscopy)
For advanced stage colorectal cancer: Open surgery to remove the cancer and surrounding colon tissues and lymph nodes (glands)

2. Chemotherapy

Can be used on its own or in combination with surgery, especially for stage 3 colon cancer and above, to shrink the cancer before attempting to remove it. It is not used in earlier stages as it confers no significant benefit to the treatment outcome and risks exposing patients to harmful side effects.

3. Radiation therapy (high-energy x-rays)

External beam radiation therapy, intraoperative radiation therapy, brachytherapy.

4. Immunotherapy

The use of a group of drugs that modulates a person’s immune system to better recognise and destroy cancer cells.

Following are some commonly deployed treatment lines based on the stage of cancer:

Stage 0: Surgery to remove the tumour growth.
Stage 1: Surgery to remove the cancerous growth.
Stage 2: Surgery is done to remove the cancerous growth followed by chemotherapy. This is required only in cases where cancer is suspected to be a high grade or if the patient has other health conditions.
Stage 3: Surgical removal of tumour and affected lymph nodes followed by chemotherapy. For some patients, radiation therapy may also be suggested.
Stage 4: Treatments could be a combination of surgery, chemotherapy, and sometimes radiation therapy. Doctors may also recommend immunotherapy and targeted therapy for some patients.

It is important to note that the treatment option is not singularly dependent on stage but may take into consideration other factors such as overall health of the patient, age, other co-existing medical conditions, etc.

In advanced stages where the great extent of cancer has been established at diagnosis, treatment is often directed at palliation (to relieve symptoms caused by the tumour and keep the person comfortable for as long as possible).

Palliative care includes:

Maintenance of adequate nutrient intake through meal planning and care.
Adequate pain management, mostly through pain medication.
Maintenance of physical condition through some form of exercise, which may vary based on the patient’s age.
Prevention of avoidable hospital admission (e.g., chest physiotherapy to prevent pneumonia).
Psychosocial support from health professionals including mental health counselling, group-based support systems or spiritual support.

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

What can I do to reduce the risk of developing colorectal (colon) cancer?

The following healthy habits can help prevent colorectal cancer:

Eat a healthy balanced diet:
- Eat plenty of fibre-rich foods, fruits, vegetables, and whole grains.
- Reduce intake of red meat, processed foods and excessive charred or barbecued meat.
Exercising regularly.
Stop smoking and reduce alcohol intake.
Maintain a healthy body weight.
Consider getting screened to catch colorectal cancer early.

Frequently asked questions (FAQs)

1. What is the difference between a cyst and a polyp? What exactly are polyps?

Cyst is an air, fluid or semi-solid substance filled cavity which can develop in any part of the body including bones, organs, or soft tissues.

Polyp is an abnormal growth of tissue, protruding from the mucous membrane. Polyps are abnormal tissue growths which are most commonly found in the colon, but can also be found in the stomach, uterus, throat, and nose.

2. I found blood in my stool. Is it colorectal cancer?

Don’t worry, blood alone isn’t a reason to panic. It could point to a number of things such as haemorrhoids, anal fissures, or other diseases. It is only when coupled with other colorectal cancer symptoms – irregular bowel movements, fatigue, sudden weight loss, feeling like your bowels have not emptied properly – that you should make a medical appointment as soon as you can.

3. When do I need to get screened for colorectal cancer?

The average individual is recommended to screen for colorectal cancer starting at around the age of 45. However, those who have risk factor(s), e.g., family history of colorectal cancer, should consider getting screening earlier. Screening tests helps detect the presence of precancerous polyps, so that they may be removed before they develop into cancer. Colorectal cancer screening tests can also detect cancer early when therapy is most effective.

4. I have a family history of colorectal cancer. Should I get screened earlier?

A strong family history of colorectal cancer should definitely be shared with your doctor. While in theory it means you have an increased risk of developing colorectal cancer versus the general populace, your doctor would be the best equipped to advise whether an early screening is needed.

5. What are the screening methods for colorectal cancer?

The best method to check for polyps and colorectal cancer is colonoscopy. You will be sedated, and the doctor would view the entire colon using a long, flexible scope. If polyps are found, they can be removed during the procedure and tested for cancer.

Faecal occult blood test (FOBT) is a lab test that checks for the presence of blood in the stool. The stool is collected at home in sample tubes, which are then sent to a lab.

If you notice any changes in your bowel habits or if you notice any symptoms of colorectal cancer, do seek medical attention.

6. How should I prepare for a colonoscopy?

Prior to a colonoscopy, your doctor may advice you to clear your colon as the imagery of your colon and rectum may be blocked by any existing residue while you are being examined.

You may need to eat a specific diet prior to your examination day or consume a prescribed bowel preparation to assist in the clearing of your colon. Some patients use an enema kit to facilitate colon cleansing.

7. What happens during a colonoscopy?

One of the preparations for colonoscopy involves wearing a gown and receiving sedation via an intravenous injection. This is designed to reduce any discomfort you may experience.

During the examination, the doctor will place you lying on your side on the exam table. The doctor will then insert a colonoscope into your rectum, which allows air to be pumped into your colon to facilitate a clearer view of your colon lining. You may feel abdominal cramping or the urge to pass motion movement whenever the scope is moved, or air is introduced.

The colonoscope has a tiny video camera at its tip, which is used to display images of the insides of your colon on an external monitor. Your doctor may also insert other instruments to take tissue samples (biopsies) from areas of abnormal tissue or remove polyps.

8. Will I need time to recover after my colonoscopy?

You will be sedated for the colonoscopy, so you might still be drowsy after the procedure. You will need a family member or friend to drive you home. That being said, it is also best to take a day off from work to rest.

Myths & facts

1. Myth: Colorectal cancer is a man’s disease.

Fact: While it is true that it is more common amongst men, colorectal cancer is still in the top four most common cancers in the world today. The lifetime risk of being diagnosed with colorectal cancer is about 1 in 20 for both sexes.

2. Myth: As a woman, I don’t need to go for a colonoscopy.

Fact: Anyone aged over 45 should get a colonoscopy, especially if you have a family history of the disease. Don’t worry, the procedure is only required every 10 years. However, if you are experiencing any symptoms before that age of 45, do talk to your doctor about having a colonoscopy earlier.

3. I’m 45, but I don’t have any symptom, so I don’t need a colonoscopy.

Fact: People can be diagnosed with colorectal cancer despite feeling fine. With age comes an increased risk of colorectal cancer, so don’t put off a colonoscopy just because you are not feeling ill. A colonoscopy is even more critical if one has a history of bowel disease or polyps. That is the whole purpose of the procedure, to check the condition of your colon.

4. Myth: Everyone is at equal risk of getting colorectal cancer.

Fact: Diet, ethnicity, age, and lifestyle play a large part in developing colorectal cancer. Studies show that different cultures and ethnicities around the world are more susceptible to different cancers based on tobacco use, dietary inclinations, and exercise. The most important take out is to realise that a good diet, active lifestyle, and regular screening can really make a difference.

5. Myth: I know someone who had colorectal cancer in their 20s. It could happen to anyone.

Fact: The chances of a younger person getting colorectal cancer is much lower. Some would go as far as to call it a medical anomaly. Unless you are showing actual symptoms, we advise you not to worry. Talk to your doctor to put your mind at ease.

6. Myth: If I have polyps, I have colon cancer.

Fact: Not all polyps are cancerous. They are initially benign and the process of turning cancerous usually takes about 5 to 10 years, which is why screening is only recommended every decade. Of course, cases differ across individuals, and it is always best to talk to your doctor, especially if you have a family history of cancer.

7. Myth: Colorectal cancer can’t be prevented. If it happens it happens.

Fact: This type of cancer is actually highly preventable. If screenings are done when symptoms are present, it can allow your doctor to detect and remove polyps (abnormal growths in the colon lining), which could lead to colorectal cancer, with a colonoscopy. Also, eating a high fibre and low-fat diet, and avoiding tobacco products and processed meats will make a difference in keeping your colon healthy.

8. Myth: A colonoscopy is super expensive!

Fact: A colonoscopy definitely costs more than the regular health screenings, but you only need to get screened every 10 years starting from age 45. Taking that into consideration, it is actually very affordable.

9. Myth: I heard a colonoscopy is a horrible experience!

Fact: The procedure takes just about 15-30 minutes, and you will be sedated throughout. The most difficult part of the whole experience is probably fasting the day before (only liquids are allowed) and taking a bowel-cleansing agent to evacuate the bowels before the colonoscopy. At most it might be a little unpleasant, but generally painless.

10. Myth: Colorectal cancer requires extensive long-term treatment.

Fact: Every patient should undergo a specific treatment plan customised by their medical expert. Colorectal cancer is treated by a colorectal surgeon and an oncologist, in what is known as a multidisciplinary approach. Discovering the disease in the early stages means it might be curable with surgery, which can range from open, laparoscopic to robotic procedures.

Make an appointment at Pantai Hospitals

Early detection of colorectal (colon) cancer makes it easier to treat the disease with effective and appropriate treatment. A dedicated multidisciplinary team of specialists and oncologists at Pantai Hospitals is available for consultation to provide the best care and assistance to patients through screening, diagnosis, and treatment.

Get in touch with us to book an appointment today if you have any concerns or questions about colon cancer treatment options.

Pantai Hospitals have been accredited by the Malaysian Society for Quality in Health (MSQH) for its commitment to patient safety and service quality.

Colorectal Cancer (Colon Cancer): Symptoms, Diagnosis, Treatment, Prevention