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Competing-Risk Nomogram for Predicting Cancer-Specific Survival in Multiple Primary Colorectal Cancer Patients after Surgery
Published on: September 27, 2024
Risk of metachronous advanced neoplasia was comparable between patients with 1-2 and 3-4 non-advanced adenomas
Zhiyu Dong1, Yanglei Li1, Ouyang Li1
1Department of Gastrointestinal Endoscopy, Huadong Hospital, Fudan University, Shanghai, China.
Background:
Current post-polypectomy guidelines classified 3-4 non-advanced adenomas (NAAs) as carrying an intermediate risk of metachronous advanced colorectal neoplasia (ACRN), positioned between that of 1-2 NAAs and > 4 NAAs. However, emerging evidence suggested that individuals with 3-4 NAAs may have a risk comparable to those with 1-2 NAAs. This study aimed to compare the risk of metachronous ACRN between individuals with 1-2 NAAs and 3-4 NAAs.
Methods:
A two-center retrospective cohort study of individuals with NAAs and subsequent surveillance colonoscopy was conducted. Cox regression models were used to compare the risk of metachronous colorectal neoplasia (CRN) and ACRN between individuals with 1-2 and 3-4 NAAs.
Results:
2955 individuals who had NAAs removed during baseline colonoscopy were included. The risk of metachronous CRN in individuals with 1-2 NAAs was significantly lower than that in those with 3-4 NAAs (adjusted HR (95% CI), 1.28(1.04-1.57)) and those with > 4 NAAs (adjusted HR (95% CI), 1.52(1.10-2.10)), while the cumulative incidence and risk of metachronous ACRN in individuals with 1-2 NAAs was comparable with that in those with 3-4 NAAs (adjusted HR (95% CI), 0.64(0.18-2.23)) and significantly lower than that in those with > 4 NAAs (adjusted HR (95% CI), 4.69(1.51-14.6)).
Conclusions:
In this observational study, the risk of metachronous ACRN after removal of 1-2 and 3-4 NAAs was comparable and lower than that observed after removal of > 4 NAAs. These findings suggest that individuals with 3-4 NAAs may have a similar risk profile to those with 1-2 NAAs. Further prospective studies are warranted to determine the optimal surveillance interval for this subgroup.
