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Colonoscopy: Screening for Colorectal Cancer

In the realm of preventive healthcare, screening colonoscopy stands as a beacon of hope, offering a powerful tool to safeguard against the insidious threat of colorectal cancer. This minimally invasive procedure, performed by a skilled colorectal surgeon, provides a comprehensive examination of the colon and rectum, enabling the detection and removal of precancerous polyps before they have the chance to evolve into malignant tumors.

The Insidious Nature of Colorectal Cancer

Colorectal cancer, often referred to as colon cancer, is a cunning adversary that often develops silently, without causing any noticeable symptoms in its early stages. This insidious nature makes it all the more crucial to embrace regular screening colonoscopies, as they offer the best chance of early detection and successful treatment.

When left undetected, colorectal cancer can progress relentlessly, infiltrating surrounding tissues and eventually spreading to distant organs. This uncontrolled growth can lead to a range of debilitating complications, including bowel obstruction, anemia, and liver metastases.

Colonoscopy is a procedure used to view the large intestine (colon and rectum) using an instrument called a colonoscope, a flexible tube with a small camera and light source attached to its tip. Colonoscopy can be performed for screening or diagnostic purposed. While diagnostic colonoscopy is performed to confirm the presence of colorectal cancer or colorectal polyps from a person showing symptoms (blood in stools, anaemia, etc.), screening colonoscopy is performed on an asymptomatic person without any prior history of the two conditions.

Screening colonoscopy is indicated for the following:

  • Family history (first degree relative) of colon cancer or polyps
  • Inflammatory bowel disease

Colonoscopy is usually performed under sedation on an outpatient basis. You will be given a laxative or enema preparation to clear your bowels before the procedure. Air will be pumped into the colon to expand it for better visibility. The colonoscope is inserted into the rectum and gently moved up the colon until it reaches the caecum (junction of small and large intestine). The colonoscope is then withdrawn slowly as the camera relays pictures of the colon and rectum lining onto a large screen for your doctor to view. Any polyps or growths detected by colonoscopy can usually be removed immediately and sent to determine whether it is cancerous or not (biopsy).

The Advantages of Screening Colonoscopy

Compared to other screening modalities, such as stool tests and CT colonography, screening colonoscopy stands out as the gold standard for detecting and preventing colorectal cancer. Its advantages are multifaceted:

  • Direct Visualization: Colonoscopy allows for a direct visualization of the colon and rectum, enabling the identification of even the smallest abnormalities.

  • Removal of Precancerous Polyps: During the procedure, precancerous polyps can be safely removed, effectively preventing their progression to colon cancer.

  • Accuracy and Reliability: Colonoscopy boasts a high degree of accuracy and reliability, providing a definitive diagnosis of colorectal abnormalities.

  • Long-Term Protection: In early removal of polyps, one can prevent a proportion of cancers from ever occurring. A single colonoscopy can provide protection against colorectal cancer for up to ten years, making it a cost-effective and efficient prevention as well as screening method.


Screening colonoscopy is a very sensitive test. However, some cancers, small polyps or non-polypoid lesions may go unnoticed, and may eventually still go on to become something more sinister. The procedure itself, and any biopsy or polyp excision, has a risk of bleeding or perforation of the colon lining. These may require subsequent surgery to repair.

American Colorectal Screening Guidelines

The American Cancer Society (ACS) recommends that adults aged 45 years and older undergo regular screening colonoscopy. Individuals with a family history of colon cancer, personal history of colon polyps, or certain inflammatory bowel diseases may need to start screening earlier or at shorter intervals.

Lead From Behind: Shining a Light on Colorectal Cancer

The "Lead From Behind" organization is championing a noble cause – bringing colorectal cancer out of the shadows and into the spotlight. Their mission to "make colorectal cancer famous" is crucial in raising awareness, dispelling misconceptions, and encouraging early detection through regular screening colonoscopies.

Partnering with a Colorectal Surgeon

Schedule a consultation with your local doctor to determine the appropriate screening schedule for you. Early detection is the cornerstone of successful colorectal cancer treatment, and screening colonoscopy is the key to early detection. Embrace this preventive measure and empower yourself to take charge of your colorectal health

Discovery Health now supports Screening Colonoscopy as a safe and cost effective way to screen for colorectal cancer.

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