Having a colonoscopy is the best way to check and screen for colorectal cancer (CRC). A small camera on a bendy tube is passed through the anus and into the colon, to view inside and collect samples. It involves a few hours of a person’s time, and they can choose medication for sedation, to make the procedure more comfortable.

For people without a family history of CRC, colonoscopy screening every 10 years is recommended. Researchers report that this interval could be extended.

The researchers used a Swedish register of data and selected two groups of people to compare. The first group consisted of people who had a first colonoscopy showing no signs of cancer (negative findings) with a follow-up colonoscopy after 10 years. The second group (the control group) consisted of people who were matched to the first group for characteristics such as age and sex, but did not have a follow-up, or had a follow-up colonoscopy that resulted in a CRC diagnosis. The researchers recorded and compared the numbers of CRC diagnosis and CRC-specific deaths in each group, over the 29 years of follow-up. 

The researchers used statistical methods to calculate the risks of a CRC diagnosis or CRC-specific death in each group. They found that, until 15 years after first negative colonoscopy, the risk continued to be low. Therefore, they propose that, for people with no family history of CRC and no cancer detected in their first colonoscopy, the time period for a follow-up colonoscopy could be extended to 15 instead of 10 years. This would avoid unnecessary invasive tests for patients and also have time- and cost-saving benefits for healthcare providers.

Reference

Liang Q, Mukama T, Sundquist K, Sundquist J, Brenner H, Kharazmi E, Fallah M. Longer Interval Between First Colonoscopy With Negative Findings for Colorectal Cancer and Repeat Colonoscopy. JAMA Oncol. 2024 May 2:e240827. doi: 10.1001/jamaoncol.2024.0827. Epub ahead of print. PMID: 38696176; PMCID: PMC11066766.

Link to the published paper

Author:
Fiona Beck