Surveillance guidelines for serrated polyps are based on limited data on longitudinal outcomes of patients.
Dr Joseph Anderson and colleagues from New Hampshire, USA used the New Hampshire Colonoscopy Registry to evaluate risk of clinically important metachronous lesions associated with serrated polyps detected during index colonoscopies.
The research team collected data from a population-based colonoscopy registry that has been collecting and analyzing data on colonoscopies across the state of New Hampshire since 2004, including rates of adenoma and serrated polyp detection.
Patients completed a questionnaire to determine demographic characteristics, health history, and risk factors for colorectal cancer, and were followed from index colonoscopy through all subsequent surveillance colonoscopies.
|Large index serrated polyps alone increased the risk of a large metachronous serrated polyp|
The team's analyses included 5433 participants with 2 colonoscopies.
The researchers used multivariable logistic regression models to assess effects of index serrated polyps, high-risk adenomas, low-risk adenomas, and no adenomas on subsequent high-risk adenomas or large serrated polyps on surveillance colonoscopy.
Synchronous serrated polyps, within each index risk group, were assessed for size and by histology.
Serrated polyps comprize hyperplastic polyps, sessile serrated adenomas/polyps, and traditional serrated adenomas.
The doctors referred to sessile serrated adenomas/polyps and traditional serrated adenomas collectively as STSAs.
High-risk adenomas and synchronous large serrated polyps, high-risk adenomas with synchronous STSA, and high-risk adenomas alone at index colonoscopy significantly increased the risk of metachronous high-risk adenomas compared to the reference group.
Large index serrated polyps alone or index STSA alone significantly increased the risk of a large metachronous serrated polyp.
In an analysis of data from a population-based colonoscopy registry, the researchers found index large serrated polyps or index STSA with no index high-risk adenomas increased risk of metachronous large serrated polyps but not metachronous high-risk adenomas.
Dr Anderson's team concludes, "High-risk adenomas and synchronous serrated polyps at index colonoscopy significantly increased risk of metachronous high-risk adenomas."
"Individuals with high-risk adenomas and synchronous large serrated polyp or any STSA could therefore benefit from close surveillance."