Although lung cancer (for men) and breast cancer (for women) are the commonest cancers in Singapore, it is actually colorectal cancer that is the most common when the tally for men and women are combined.
Despite this, far fewer go for colorectal screening than for mammograms.
Colorectal, or bowel cancer, is curable if diagnosed early.
If everyone were to go for colonoscopy once every three years, almost no one would die of colorectal cancer. Few would ever need to go for colorectal surgery and even fewer would need the surgical procedure called a colostomy.
A colostomy involves connecting a part of the colon onto the anterior abdominal wall, leaving the patient with an opening on the abdomen called a stoma.
In a colostomy, the stoma is formed from the end of the large intestine, which is drawn out through the incision and sutured to the skin. After a colostomy, faeces leave the patient's body through the stoma. The stoma may be permanent or temporary, depending on the reasons for its use.
What has put people off screening then? Three reasons: Cost, discomfort and the procedure's invasive nature.
Before a colonscopy, the bowels have to be 'cleaned". The evening before, the patient drinks two litres of water laced with an awful-tasting liquid to induce massive diarrhoea. He then sits on the toilet bowl for hours.
In colonoscopy, an endoscope is inserted through the anus and carefully tracked up the rectum, negotiated along the colon all the way till the caecum (where the small intestine joins the large intestine). The patient suffers no discomfort because it is usually done under light sedation.
Some years ago, I decided to practise what I preach and went for my first colonoscopy. As expected, the bowel preparation was no fun. The next day, I began my ward rounds at 6.30am as usual. At about 8am, I received a call from my colleague, a colorectal surgeon, telling me that the endoscopy suite was available.
I trotted down the stairs to the ward, changed into the hospital 'baju" and was put on a trolley bed. The anaesthetist, another good friend, inserted an intravenous line and said, 'Okay, you are going to feel a little stinging pain as this anaesthetic goes...' Lights out.
The next thing I knew, I was back in the ward and the colorectal surgeon was there to give me the all-clear. It was that simple. I changed back to my office attire and carried on with my ward rounds as though nothing had happened.
This simple procedure can save lives - many lives.
Each year, about 2,000 new cases of colorectal cancer are diagnosed. Colorectal cancer does not develop overnight. It is believed that it takes at least two or more years to develop. These cancers start off as benign growths (called polyps) on the inner lining of the bowel. These polyps are easily detected in a colonoscopy and can be removed at the same time without much difficulty. Once removed, the polyps do not get a chance to turn cancerous.
Yet, over the years, I have been reminded many times that medicine is not just about treating the body but also treating the patient's decisions with respect. Sometimes, this entails not a little frustration.
I have a patient, a man in his 70s, whom I have been looking after for the past five months. He was diagnosed with colorectal cancer - in his case, the rectum - about a year ago. His cancer lies just about 4cm from the anal opening. Because of its position, surgery will entail removing the tumour together with his anus.
As he would not be able to control his faecal waste after the surgery (called an abdominal perineal resection), an opening on his abdominal wall will have to be created to allow the discharge of his stools into a colostomy bag.
The surgeon tried to convince him of the importance of surgery but he flatly refused. He avoided follow-up and ended up seeing me many months later when he had difficulty passing motion.
By the time he saw me, a computer tomogram (CT) scan showed two nodules in the lung, indicating that the cancer had already spread. Still, after six cycles of chemotherapy, his scan was normal, which was great.
Seizing on this, I spent a long time explaining the potential benefits of surgery but he remained unconvinced. A man of few words, he said in Hokkien: 'No! No means no!"
Many fear the indignity and hassle. In fact, having a colostomy is not a big deal. Those who have had a colostomy tell me that it initially takes some getting used to but after that, it is no different from changing a diaper.
The Singapore Cancer Society has a cancer support group called Stoma Club. Volunteers, who themselves have had a colostomy, call upon patients either before or after surgery to offer psycho-social support and advice.
I have given my patient the hotline number to call. Hopefully, this time round, rather than dying slowly from a cancerous rectum, he will choose to 'renew' life with a stoma.
This is the last of a three-part series on the three top cancers in Singapore: lung, breast and colorectal cancer.
Dr Tan, the medical director of Parkway Cancer Centre, has been treating cancer patients for nearly 20 years. In 1996, he was awarded Singapore's National Science Award for his outstanding contributions to medical research.
-------------------------------------------------------------------------------- 2,000 new cases of colorectal cancer are diagnosed every year
This story was first published in the Mind Your Body supplement on Apr 9, 2008.
