Editor: Sally Heading
Motivation behind the research
Around one in twenty people will develop colon cancer in their lifetime. Without screening this silent killer usually, goes unnoticed until it is too late. Screening programs have been introduced in many countries to reduce colon cancer deaths, mostly through the detection of polyps that have the potential to progress to cancer. Where possible, polyps are removed during a screening colonoscopy, however, removing polyps is not without risk, and the risk increases with polyp size.
Most screening programs continuously assess the complications of the colonoscopies performed. Colonoscopists with higher rates of complications will be approached to explain themselves or undergo extra training. Despite the best intentions of this strategy, it can lead to the avoidance of higher risk polyp removals, with patients instead of being referred for surgical removal. This is not only more expensive but also carries a far higher risk of serious injury or death. While endoscopic removal is technically possible for all polyps regardless of size or location, there are large variations in practice between centres and many patients worldwide continue to receive surgery for polyps unnecessarily.
We set out to investigate the complication rate of endoscopic polyp removal, with a particular focus on complications associated with large (>2cm) polyps, and very large polyps (>4cm), in the higher risk elderly patients.
We found that, even in the highest risk group, endoscopic polyp removal is safe, with no difference found in the complication rate between the elderly patient group (over 75) and the non-elderly group (under 75). Out of 343 patients with large polyps, there were no deaths and only one patient required surgery due to a perforation. Bleeding was the main complication of endoscopic removal of large polyps, occurring in 5% of polyps 2-4cm in size and 11% of polyps >4cm. Only 25% of patients with bleeding complications after polyp removal needed a blood transfusion and the average hospital stay was only 2 days.
This was a retrospective study. No routine biopsies were performed of the scar when the site of polyp removal was checked and not all patients came back to have the scar site checked.
Our next research project aims to investigate the removal of large polyps present in the rectum. Polyps in this area have a higher likelihood of being cancerous and additional surgery can lead to the permanent requirement of a colostomy bag, and therefore non-surgical removal is a more desirable outcome. We will randomise patients between the best endoscopic removal option, Endoscopic Submucosal Dissection (ESD) as developed in Japan, and the best non-invasive surgical option, Transanal Minimally Invasive Surgery (TAMIS) to see which is the safest and most cost-effective approach.
Call to action: Screening organisations should encourage the endoscopic (as opposed to surgical) removal of all polyps regardless of size and the age of the patient. This should be concentrated in expert centres as recommended in recent European guidelines.
Research article: Safety of endoscopic mucosal resection (EMR) of large non-pedunculated colorectal adenomas in the elderly, International Journal of Colorectal Disease, 2017.