Colonoscopy is a widely used screening test to detect colorectal cancer. The US Preventive Services Task Force recommends adults between the ages of 45 to 75 be screened, while the decision to be screened between ages 76 and 85 should depend on the individual.
People at an increased risk of cancer should talk to a doctor to begin screening and talk about which test and how often it should be administered. The new study explores the effect of colonoscopy screening on the risks of colorectal cancer.
What Is Colonoscopy Screening?
There are several screening tests that can be used to find colorectal cancer or polyps, per the Centers for Disease Control and Prevention (CDC). These tests include stool tests, flexible sigmoidoscopy, CT colonography (virtual) colonoscopy), and colonoscopy. Among these tests, colonoscopy is mostly used but its effects on colorectal cancer and related death remain unknown.
In colonoscopy screening, the doctor uses a long, thin, flexible, lighted tube and inserts it into the rectum and the entire colon. The equipment helps the doctor check for polyps or cancer inside the rectum and colon.
Colonoscopy screening helps early diagnosis of polyps and cancer, and doctors could remove them during the test. It also serves as a follow-up test if doctors find anything unusual during one of the other tests. Doctors recommend people to undergo colonoscopy screening every 10 years even for those who do not have an increased risk of colorectal cancer.
Risk of Colorectal Cancer
According to Cancer.Net, someone with an average risk of colorectal cancer has an overall 5% chance of developing colorectal cancer. Generally, 95% of colorectal cancer is considered sporadic or that genetic changes develop by chance after the person is born which is why inherited colorectal cancer is less common.
Usually, the cause is not known; but there are factors that may increase the risk of developing colorectal cancer. These factors are age, race, gender, family history, rare inherited conditions, inflammatory bowel disease, adenomas, personal history of cancer, physical inactivity or obesity, diet, and smoking.
READ ALSO: Colorectal Cancer Appears More in Taller People, Study Suggests
Effect of Coloscopy on the Risk of Colorectal Cancer
In the study titled "Effect of Colonoscopy Screening on Risks of Colorectal Cancer and Related Death" published in The New England Journal of Medicine, researchers conducted a randomized trial involving healthy men and women ages 55 to 64 from Poland, Norway, Sweden, and the Netherlands between 2009 and 2014.
The participants are randomly assigned in a 1:2 ratio to receive an invitation to undergo a single screening colonoscopy and the other group did not receive an invitation or screening.
The results showed that 15 participants had major bleeding after polyp removal while there are no screening-related deaths that occurred within 30 days after the colonoscopy screening. During a follow-up after 10 years, 259 cases of colorectal cancer were recorded among those who were invited for a colonoscopy screening compared to the 689 cases of those who did not have the test.
Based on their analysis, the invited group had a 0.98% risk of colorectal cancer after 10 years while the uninvited group who only received the usual care had a 1.2% risk.
Moreover, the risk of death from colorectal cancer was 0.28% in the invited group and 0.31% in the usual care group. Researchers wrote that the number of participants who needed to invite to undergo the screening was 455.
They concluded that the risk of colorectal cancer at 10 years was lower in the invited group who underwent colonoscopy screening than those who did not have the test.
RELATED ARTICLE: Colorectal Cancer Linked to Greater Red Meat Intake, Poor Educational, Heavier Alcohol Use
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