Silent killer: Colon cancer highly treatable, but third leading cause of cancer deaths

KUALA LUMPUR, Nov 21 — The mere mention of the word “cancer” often evokes a sense of dread and anxiety among people, as it is commonly associated with uncertainty and mortality.

Despite significant advancements in medical research and treatment options that have improved survival rates and quality of life, many individuals still shy away from discussing the topic.

That probably may be the reason why colorectal cancer has emerged as the most prevalent cancer in Malaysia after breast cancer.

Despite being one of the most treatable types of cancer, particularly when detected in its early stages, it is the leading cancer affecting Malaysian men.

According to the Malaysia National Cancer Registry Report 2017-2021 report released by the Health Ministry this year, colorectal cancer affects approximately 19 out of 100,000 Malaysian men, which is a 20 per cent increase from the 2012-2016 report.

Among women, it ranks second, impacting about 14 per 100,000 individuals.

Alarmingly, this condition stands as the third leading cause of cancer-related deaths in the country.

What is colorectal cancer?

Colorectal cancer refers to cancer that starts in the colon or rectum, both parts of the large intestine.

The disease often begins as benign clumps of cells known as polyps on the inner lining of the colon or rectum.

Over time, some of these polyps can turn cancerous, leading to the development of colorectal cancer.

Therefore, the key to successful treatment is early identification, but unfortunately, symptoms often manifest only in more advanced stages.

Causes and risk factors

The specific causes of colorectal cancer are not entirely understood; however, a variety of risk factors have been identified.

Ageing plays a significant role, with most cases occurring in people aged 50 and older.

Additionally, diets high in red or processed meats can elevate risk levels while a sedentary lifestyle and obesity are further risk enhancers.

Other significant factors include smoking, excessive alcohol consumption, and certain inherited gene mutations such as Lynch syndrome.

According to public health physician and National Cancer Society of Malaysia managing director Dr Murallitharan M, one of the major drivers of colorectal cancer is poor nutrition.

“Any kind of processed meat and excess consumption of red meat is strongly linked to colorectal cancer,” he said.

Signs and symptoms

The symptoms of colorectal cancer can be subtle or mimic those of other conditions, which makes early diagnosis challenging.

Common signs include persistent changes in bowel habits such as diarrhoea or constipation, rectal bleeding or blood in the stool, abdominal discomfort such as cramps or pain, a feeling that the bowel does not empty completely, weakness or fatigue, and unexplained weight loss.

Recognising these symptoms and seeking medical advice can lead to earlier detection and more successful treatment outcomes.

Is colorectal cancer treatable?

Colorectal cancer is indeed treatable, particularly when diagnosed in the early stages.

Treatment modalities include surgery, chemotherapy, radiation therapy, targeted drug therapies, or a combination of these approaches.

The effectiveness of treatment diminishes as the disease progresses, which highlights the crucial role of early diagnosis in improving patient outcomes and survival rates.

The importance of early detection

Early detection can dramatically improve survival rates for colorectal cancer.

Unfortunately, many Malaysians are diagnosed at advanced stages of the disease.

According to the registry’s data, 74.7 per cent of Malaysian patients discover their condition at Stages 3 and 4.

At these stages, the prognosis is dire, with five-year survival rates plummeting to 55.6 per cent for stage 3 and only 17.3 per cent for stage 4.

According to Dr Murallithara, a lot of people wrongly think colorectal cancer is an elderly disease which is no longer true.

“Secondly, people also think colorectal cancer is only a family-related disease.

“It is partially true as genetic linkage may cause certain diseases like cancer but it’s not limited to those with a family history of colorectal cancer,” he said.

How is colorectal cancer detected?

Detection of colorectal cancer primarily relies on screening methods, which are crucial for catching the disease early.

According to Dr Murallitharan, the reason why most Malaysians catch the disease at a later stage is due to selecting the wrong choice of screening option.

“A lot of people think the screening for colorectal cancer is through a blood test.

“Most of the time, the tumour marker tests can be inaccurate and may not show you have colorectal cancer,” he said.

Dr Murallitharan said the most effective and widely used method is colonoscopy, which involves a comprehensive examination of the colon and rectum using a long, flexible tube with a camera.

Other diagnostic tools include faecal occult blood tests, which detect hidden blood in the stool, and CT colonography, which uses imaging to examine the colon.

These methods enable healthcare providers to identify cancerous growths or precancerous polyps before symptoms arise.

Treatment options

Treatment for colorectal cancer is multifaceted and depends on the stage and location of the cancer.

Surgical options are often employed to remove the cancer, which may suffice for early-stage cancers.

However, more advanced cancers might necessitate additional treatments such as chemotherapy to kill cancer cells, radiation therapy to shrink tumours, or targeted therapies that specifically attack cancer cells with minimal harm to normal cells.

The combination of these treatments is tailored to each patient to enhance effectiveness and improve outcomes.

Can you prevent colorectal cancer?

While not all cases of colorectal cancer can be prevented, lifestyle modifications can significantly reduce risk.

Adopting a diet rich in fruits, vegetables, and whole grains, while limiting intake of red and processed meats may be a positive lifestyle change towards a healthier routine.

Regular physical activity and maintaining a healthy weight are also important preventive measures.

Additionally, avoiding tobacco use and moderating alcohol consumption may lower risk levels.