June 13, 2024
Nobody wants to have a conversation about getting screened for colon cancer, but this type of cancer is much more common than you would think. In fact about 1 in 16 Canadian men and 1 in 18 Canadian women will develop colorectal cancer during their lifetime. Proactive testing is more important than ever; making informed decisions about preventive healthcare, especially for conditions like colorectal cancer, can be lifesaving. Let's take a little time to look at different methods for colorectal cancer screening and why early detection is so important.
Colorectal cancer begins in the cells of the colon or rectum, forming a malignant tumor that can grow into nearby tissue or spread to other parts of the body. Both the colon and rectum are integral parts of the large intestine and the digestive system, with the colon playing a key role in absorbing water and nutrients and passing waste to the rectum. This type of cancer encompasses both colon and rectal cancers due to their shared tissue type and the lack of a clear border between these organs.
Why is Screening Important?
The Fecal Immunochemical Test (FIT) is a primary method for colon cancer screening, offering a non-invasive, at-home option. A small sample kit is sent home and a tiny amount of stool is collected and lab tested. This test detects hidden blood in the stool, a possible indicator of colorectal cancer or precancerous polyps. Simple and quick, FIT requires no dietary or medication changes, making it a convenient choice for many. An abnormal FIT result necessitates further investigation, typically a colonoscopy, within 8 weeks. Regular screening with FIT is advised every 2 years up to age 74 for those with normal results.
A colonoscopy allows for a comprehensive examination of the entire colon and rectum. This procedure involves a long, flexible tube equipped with a camera, providing a detailed view of the colon to detect any abnormalities. It is the most sensitive test available for colon cancer screening, capable of removing polyps and taking biopsies during the exam. Preparation includes a thorough cleansing of the colon and dietary adjustments. Recommended every 10 years for individuals with no abnormalities found and no increased risk of colon cancer, a colonoscopy is the follow-up test for abnormal FIT results.
Flexible Sigmoidoscopy is another screening option, focusing on the lower part of the colon. This procedure uses a flexible tube with a camera to inspect the rectum and sigmoid colon for any signs of cancer or polyps. It requires less preparation than a colonoscopy, often without the need for sedation, and takes about 20 minutes. While it offers a quicker, less invasive option, it does not examine the entire colon. If abnormalities are detected, a colonoscopy may be recommended for a more thorough investigation.
Individuals aged between 45 to 74 years, who do not show symptoms of colorectal cancer (CRC) and have no family history of the disease, fall into the average risk category. For these individuals, it is recommended to undergo screening with a fecal immunochemical test (FIT) every 2 years. Should the FIT results indicate abnormalities, a follow-up colonoscopy should be conducted within 8 weeks to investigate further. This proactive approach aims to detect any early signs of colorectal cancer or precancerous polyps, offering a significant step towards preventive health care.
People considered at increased risk for colorectal cancer include those with a family history of the disease, particularly if one or more first-degree relatives (parent, sibling, or child) have been diagnosed. Additionally, individuals with a personal history of colorectal cancer, non-cancerous (benign) polyps in the colon or rectum, inflammatory bowel disease (such as ulcerative colitis or Crohn's disease), or inherited conditions like familial adenomatous polyposis (FAP) or Lynch syndrome are also at higher risk. These individuals should start screening at age 45, or 10 years earlier than the age at which their relative was diagnosed, whichever comes first. Depending on their specific risk factors, the screening may involve a colonoscopy, flexible sigmoidoscopy, or stool tests like FIT, with the frequency of screening adjusted based on their family history and personal health background.
It's important to have a conversation with your healthcare provider and decide if colorectal cancer screening is a good choice for your good health.