Colorectal Cancer


The Disease

Colorectal cancer is a disease in which cancer cells form in the tissues of the colon or rectum. Globally, colorectal cancer is the third commonest form of cancer, diagnosed in more than 120,000 people worldwide in 2008. An excess of 600,000 patients were reported to have died from this disease in 2008. In Malaysia, cancers of the large bowel were the second highest type of cancer reported from 2003-2005 (11.2% of all cancers reported).

Causes & Risk Factors

The risk for colorectal cancer increases with age, and more than 90% of cases are in patients older than 50 years. In Malaysia, the incidence (number of new cases reported) of large bowel cancer increased sharply in patients aged 40 years and above. Besides age, other risk factors for developing colorectal cancer include a family history of colorectal cancer, colorectal polyps (growths on the inner wall of the colon or rectum), inflammatory bowel disease (which is more common in western countries), and cigarette smoking.

Diagnosis & Screening

Screening and diagnostic tests for colorectal cancer include faecal blood tests and visual examination of the large bowel (colonoscopies). People with colorectal cancer may also have non-specific symptoms such as a change in bowel habits (such as diarrhoea or constipation), a feeling that the bowel does not empty completely, frequent pains or cramps, or unexplained loss of weight. Regular screening is important, especially for high risk groups, as the treatment for colorectal cancer is more likely to be effective when the disease is detected at an early stage.


A variety of treatment options are available to people who have been diagnosed with colorectal cancer. The choice of treatment is dependent on the location of the tumour, and the disease stage. Therapies for colorectal cancer include the surgical removal of the cancerous tissue, radiation therapy, chemotherapy agents, or targeted therapies.

Your doctor is the best person to explain your treatment choices, the expected results, and the possible side effects to you.