EARLY DIAGNOSIS

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Symptomatic presentations often denote late stage disease. These symptoms include rectal bleeding, change in bowel habits, abdominal pain, decrease in stool caibre, passage of mucus, unexplained anaemia, bowel blockage, weight loss or loss of appetite.

The early stage cancers are mostly diagnosed from screening procedures when patients are asymptomatic and this has contributed to better survival rates in colorectal cancers.

For the last two decades, prophylactic removal of colon polyps has been the standard approach to cancer prevention. Aggressive screening and polyps removal through colonscopy can reduce the rate of colon cancer development by approximately 80 percent.

Screening methods

Faecal Occult Blood Testing (FOBT)

Colorectal cancer bleeding may not be obvious to the naked eyes especially in the early stages. The advantage of this test is to pick up early stage cancers before patient presents with symptoms. It is also noninvasive and inexpensive.

Colonoscopy

Generally considered the gold standard for diagnosing colorectal cancer, colonoscopy has the main advantage of allowing diagnosis and definitive treatment of polyps.

Virtual Colonoscopy

Formidable developments in rendering 3-dimensional images using computer graphics have produced the technology of ‘virtual colonoscopy’. First described by Vining et al in 1994, virtual colonoscopy applies techniques for rendering complex images to spiral CT scan images. The computer then generates a retrograde intraluminal “fly through” navigation from rectum to caecum and repeats it in the opposite direction, allowing a detailed 3-dimensional view of the colonic lumen similar to real colonoscopy.

Find a Colorectal Surgeon

Expert Author:

Dr Chen Chung Ming, Nobel Surgery Centre