More than 80 per cent of colorectal cancer victims in Singapore are over the age of 50. It is also the most common cancer among Singaporean men and second only to breast cancer in Singaporean women.
According to the Singapore Cancer Registry Annual Registry Report 2015, there has been an overall increase in the survival rates of colorectal cancer for both genders.
This can be attributed to early detection of the disease and improved methods of treatment, such as targeted therapies, according to Dr Zee Ying Kiat, Senior Consultant of Medical Oncology at Parkway Cancer Centre.
“Targeted therapy in particular has made great strides in recent years, especially in the treatment of patients with advanced colorectal cancer”, says Dr Zee.
Spotting and Treating Colorectal Cancer
Also known as bowel cancer, colorectal cancer can develop quietly with few symptoms.
It usually begins as a polyp or a benign growth within the rectum or the large intestine. This can turn cancerous over several years.
Once the cancer develops further, symptoms may appear.
Common symptoms include blood in the stool, a change in bowel habits, persistent pain in the abdomen, bloating or cramps, a feeling of bowels not being completely emptied, and unexplained weight loss.
As it usually takes five to ten years for a polyp to become cancerous, removing the polyp is often a recommended course of action.
According to Dr Zee, once the cancer evolves, more intensive methods of treatment will be required. These include surgery, radiation therapy, chemotherapy and targeted therapy.
“Targeted therapy works by inhibiting molecules which, through medical science, have been identified to trigger the growth and spread of cancer cells”, says Dr Zee.
There are three main methodologies of targeted therapy drugs. Some drugs work by blocking chemical signals from a molecule known as the Epidermal Growth Factor Receptor (EGFR) that tells the cancer cell to grow and divide.
Others stop new blood vessels from forming and by doing so, deprive cancer cells of oxygen and nutrients.
Lastly, some targeted therapy drugs trigger the immune system to destroy cancer cells.
Early Detection and Prevention
Screening allows for the detection of colorectal cancer, even before symptoms arise. The earlier colorectal cancer is detected, the higher the likelihood of survival.
Two commonly adopted screening methods are the Faecal Immunochemical Test (FIT) and a colonoscopy.
The FIT detects tiny amounts of blood hidden in stool, and a colonoscopy, examines the rectum and entire colon using a lighted instrument called a colonoscope. Colonoscopy can find suspicious polyps so they can be removed before they turn cancerous.
While a family history of cancer may put a person at risk, lifestyle factors such as alcohol consumption and a lack of exercise can increase the risk of colorectal cancer.
As Dr Zee points out, colorectal cancer can be prevented by making simple changes to diet and lifestyle.
“These would include regular exercise, maintaining a healthy weight, limiting alcohol consumption, avoiding tobacco, taking a diet that is higher in fruits and vegetables and lower in saturated fats and processed foods”, says Dr Zee.
Produced in partnership with Parkway Cancer Centre