Rising colorectal cancer cases
Colorectal cancer is increasing in Singapore in both men and women. Early detection remains essential.
BY: Eleanor Yap
Colorectal cancer cases in Singapore are on a rise and Singaporeans are urged to do their annual screening. Colorectal cancer is the most common cancer affecting men and women in Singapore.
In the latest Singapore Cancer Registry Interim Report 2006-2010, the incidence of colorectal cancer rose to 8,206 cases from 7,909 cases for the five-year period from 2005 to 2009. Compared with the period 1998 to 2002 where there were 6,621 cases recorded, the incidence rate has increased to 32 percent.
Agelessonline speaks to Dr Bernard Lim, senior consultant surgeon at Pacific Surgical & Colorectal Centre, about the rising cases and what should those aged 50 years and above do:
Why do you think there is an increase in the number of people getting colorectal cancer?
The rise in colorectal cancer is probably multifactorial. It may be related to diet, lifestyle and the environment. However, the increase in the number may also be due to more widespread awareness and screening, which in turn leads to an earlier pick-up and hence a relative increase, as these cases would have previously not been diagnosed till much later.
Is the condition more prevalent in men or women? What about different races?
The condition is the number 1 cancer amongst men and the number 2 cancer amongst women in Singapore, after breast cancer, right now. Race itself is not considered a risk factor.
Is colonoscopy the only screening that should be done to prevent colorectal cancer? What other methods are there?
The other methods of screening include faecal occult blood test (FOBT), barium enema or CT colonoscopy. However, the advantage of colonoscopy, other than being one of the most accurate tests, is that it is both therapeutic as well as diagnostic. This means that during colonoscopy, any precancerous polyps, which are detected, can be removed at the same time. Furthermore, anyone with a positive FOBT, barium enema or CT colonoscopy would be advised to go for a colonoscopy anyway.
So you are recommending instead of doing a FOBT, whether negative or positive, to go straight to a colonoscopy? Isn’t that kind of expensive?
True, colonoscopy is more expensive than a FOBT hence it is not possible to recommend everyone to go for it as a screening test. Each of the various methods of screening have their own pros and cons. FOBT is cheaper and non-invasive. Hence, patients should make an informed decision on the screening test after knowing the pros and cons of each. This can be done in consultation with a doctor. The cost of colonoscopy varies greatly from doctor to doctor, hospital to hospital. However, patients can use their Medisave up to a limit of S$1,250 for colonoscopy.
How often should someone over 50 years old screen for colorectal cancer?
The MOH clinical practice guidelines recommend starting from 50 years of age. If a colonoscopy is done and results are normal, and the patient continues to have no symptoms, and is not of high-risk, he can repeat the colonoscopy at an interval of five to 10 years. The individual should seek medical attention anytime a new symptom develops.
For high-risk individuals, i.e. those with family history, screening needs to start even before 50 years old. For individuals with symptoms, i.e. those with bleeding in the stool, changes in bowel habits, persistent abdominal discomfort, losing weight with no apparent reason and having nausea or vomiting, they should see a doctor regardless of age, who will assess and advise regarding colonoscopy.
What should people expect during a colonoscopy? How should they prepare themselves for it?
Colonoscopy is usually done under sedation by a trained doctor. A flexible tube (endoscope) is used to look at the lining of the rectum and colon. It is usually performed as a day procedure and overnight admission is not required. It takes approximately 15 to 20 minutes. The patient will be given instructions on diet, fasting and how to take a bowel cleansing preparation prior to the colonoscopy.
What if I have a benign polyp, will it turn cancerous? What should I do or look out for?
Yes, certain types of benign polyps, if not removed, can turn cancerous with time. The only way to tell which polyps are precancerous or not, are to have them removed during a colonoscopy and sent for a histological examination to determine the type of polyp. Hence, you should discuss with your endoscopist the results after the histological examination on the subsequent treatment or follow-up needed.
What if I find out that I have colorectal cancer? What treatment methods are there? What are the chances of it recurring?
The prognosis of colorectal cancer depends a lot on the stage of the tumour. The treatment of choice is usually surgery to remove the part of the intestine with the tumour and the surrounding lymph nodes. If it is in an early stage, surgery is adequate. For more advanced stages, chemotherapy or radiotherapy may be recommended after surgery. This will be discussed by your surgeon and oncologist.
The chance of cancer recurring depends on the stage of the cancer and the response to therapy. Patients will be placed on a surveillance follow-up programme after surgery to monitor for any recurrence.
What should people do to reduce their risks on contracting this cancer? Any lifestyle, diet or wellness tips?
Individuals may lead a healthy lifestyle with adequate exercise and a balanced diet. However, the most effective way to reduce their risk of colorectal cancer is to undergo colorectal screening. As colorectal cancer develops from polyps, if we can detect and remove these polyps via colonoscopy before they turn cancerous, we would have reduced one’s risk of cancer.
What are your thoughts on the awareness message? Is it enough? What more do you think can be done?
More can be done to raise awareness of this very important and common cancer. Most are unaware of the need for screening, and think that if they have no symptoms, they do not need to undergo screening. We know that most often, polyps or early cancer has no symptoms. Yet if detected early through screening, individuals can be prevented from getting cancer if polyps are removed. Even early stage cancer can be “cured” via surgery if detected early. Hence screening is important, even for people with no symptoms.