Meta-analysis for 6- to 9-mm Adenomas Shows Higher Risk of Subsequent Advanced Neoplasia Compared to 1 to 5 mm
Douglas K. Rex, MD, FASGE, reviewing Jung YS, et al. Gastrointest Endosc 2020 Apr 22.
Current surveillance recommendations classify patients with 1 or 2 tubular adenomas <10 mm in size and with low-grade dysplasia as low risk. Several studies have investigated whether the risk of advanced neoplasia at follow-up is greater for patients who have 1 or 2 small (6-9 mm) adenomas versus those with only diminutive (1-5 mm) adenomas.
This study is a systematic review and meta-analysis of 8 studies involving 36,142 patients. The risk of advanced neoplasm at follow-up was higher among those with 1 or 2 adenomas <10 mm in size if one or both of the adenomas was 6 to 9 mm (risk ratio, 1.49). Further, if there were 3 or more nonadvanced adenomas, the risk of metachronous advanced neoplasia was higher if there were small adenomas compared to only diminutive adenomas (hazard ratio, 1.51). The group with ≥3 diminutive adenomas had a similar risk of advanced neoplasia at follow-up as the group with 1 or 2 adenomas <10 mm in size, including a 6- to 9-mm adenoma.
COMMENTThis meta-analysis indicates that there is increased risk associated with a small adenoma compared to patients who have only diminutive adenomas. Recent guidelines recommend that patients with 1 or 2 adenomas <10 mm in diameter have repeat colonoscopy in 7 to 10 years, and those with 3 or 4 adenomas <10 mm in size have repeat colonoscopy in 3 to 5 years. Based on these results, it would be reasonable to choose 10 years and 5 years for those with 1-2 or 3-4 diminutive adenomas, respectively. Similarly, if a small adenoma is present, those with 1 or 2 total adenomas might be examined at 7 years, and those with 3 or 4 total adenomas at 3 years.
Note to readers: At the time we reviewed this paper, its publisher noted that it was not in final form and that subsequent changes might be made.
CITATION(S)
Jung YS, Kim TJ, Nam E, Park CH. A comparative systematic review and meta-analysis of 1 to 5 mm versus 6 to 9 mm adenomas on the risk of metachronous advanced colorectal neoplasia. Gastrointest Endosc 2020 Apr 22. (Epub ahead of print) (https://doi.org/10.1016/j.gie.2020.04.042)
