PETALING JAYA: A cancer diagnosis is devastating. Although great strides have been made in treating cancer, it is nevertheless a painful disease that leaves patients in fear of both the long treatment process ahead of them as well as their life expectancy post-treatment.
One of the most common types of cancer in Malaysia is colorectal cancer, and to gain a better understanding of this disease, FMT spoke to Dr Shanthi Palaniappan, a gastroenterologist and physician based in Kuala Lumpur.
“Colon or colorectal cancer is cancer that involves the lowest part of the digestive system which is the large intestine and the rectum,” she said.
There are four stages of colon cancer: in stage one, the cancer is localised within the bowel and in stage four, it has spread to other organs in the body. As such, the treatment options are determined by the stage of the cancer.
Understanding the risk factors
There are several risk factors for developing colon cancer – the first being a person’s age. “Hence, for those who are 45 years or older, experts recommend that they get screened although they may not have additional risk factors.”
Another factor, she shared, is a person’s lifestyle. This would include a diet high in fat, red, or processed meat and low in fibre; obesity; a sedentary lifestyle with little exercise; smoking cigarettes; excessive alcohol consumption; and gut microbiota, which are microorganisms that live in a person’s gastrointestinal system.
She added that some genetic familial syndromes may also increase the risk for colon cancer. The risk gets higher if a person has a first-degree relative such as a parent or sibling with cancer.
“Even if you have a relative with adenomatous polyps, your risk increases as well,” she said.
Adenomatous polyps, which are also known as adenomas, are growths on the lining of the colon that can potentially turn cancerous over time – typically over 10 years.
She also shared that this risk may be higher based on the number of family members with the cancer, and their ages when the cancer or polyps were detected.
“If your parent had the cancer at the age of 50, it is recommended that you get screened when you are 40 (i.e., 10 years earlier) than the affected relative,” she added.
Additionally, those with inflammatory bowel disease also have a higher risk of developing colon cancer.
Prevalence in Malaysia
According to the Malaysia National Cancer Registry Report 2012-2016 by the Ministry of Health, colorectal cancer is the most common cancer among Malaysian men and the second most common cancer among Malaysian women.
It was also reported that the incidence of the disease was highest among Chinese, followed by Malays and Indians.
“There is also an increasing incidence of colon cancer, especially among the younger population and this can possibly be due to three interrelated factors which are diet, bacteria in the gut, and inflammation.”
When it comes to diet, she said studies showed that an unhealthy diet and being overweight or obese may potentially increase the risk of developing the cancer at an earlier age.
“Meanwhile, an alteration in the gut microbiome has also been identified to play a role in the development of colorectal cancer. Furthermore, an unhealthy diet and certain gut bacteria can lead to inflammation in the gut, which can lead to accelerated tumour growth.”
Among the symptoms to look out for, she revealed, are abdominal pains and a change in bowel habits. “Black or dark-coloured stools, blood in the bowel movement, feeling weak or tired, having low iron levels, and experiencing a loss of appetite or weight loss are other common symptoms.
“Because some of these symptoms may be similar to other conditions such as irritable bowel syndrome, it is best to get it checked,” she shared.
Testing for cancer
There are several screening methods for colon cancer such as stool test, flexible sigmoidoscopy, colonoscopy, and CT colonography (virtual colonoscopy).
She explained the differences between a flexible sigmoidoscopy and a colonoscopy. “In the former, a short, thin, flexible, and lighted tube is inserted into the rectum and enables the doctor to check for the presence of polyps or cancer in the lower third of the colon and the rectum. Meanwhile, the latter gives access to the entire colon and the rectum.”
She added that screening aims to identify colorectal cancer at an early and curable stage, and ultimately prevent death. It can also prevent cancer by detecting precancerous abnormal growths or polyps and subsequently remove these before it turns cancerous.
It is recommended that adults undergo screening at the age of 45 years old or even earlier, she said, depending on one’s family history. The screening methods used are dependent on the individual’s preference.
Treatment and prevention
While colon cancer is usually treated with surgery, chemotherapy and/or radiation therapy, more critically, what steps can a person take to prevent developing colon cancer at all?
“Having a healthy diet that is high in vegetables, fruits, and fibre; increasing the level of physical activity; limiting alcohol consumption, and not smoking are among them.
“Meanwhile, a secondary prevention method is to undergo screening. By taking prevention steps, you are taking an active role to look after yourself,” she concluded.