New management of surveillance in patients with baseline serrated polyps: a large single-center retrospective cohort study in China

Background Serrate d polyps (SP) is associated with an increased risk of colorectal cancer. Patients with SP history tend to have SP recurrence. However, the risk factors for metachronous polyps (MP) in those patients are not well established. Methods Data of colonoscopy were retrospectively reviewed from October 2012 to October 2021. The pathology database, electronic medical records and telephone follow-up data were also observed. Results A total of 906 patients were studied including 278 patients with MPs and 628 patients without. The multiplicity of polyps (OR, 13.63; 95% CI, 8.80–21.75), older age (OR, 5.71; 95% CI, 1.87–20.63), abdominal obesity (OR, 2.46; 95% CI, 0.98–6.42), current smoker (OR, 2.93; 95% CI, 1.15–7.83) and sedentary lifestyle (OR, 1.41; 95% CI, 1.22–1.65) are significantly associated with the risk of MPs. Patients with baseline SP < 10 mm were more likely to develop higher or same risk-grade polyps (HSRGP) (P = 0.0014). Patients with non-clinically significant SPs whether coexisted with adenoma or not were more likely to develop HSRGPs when compared to others (P < 0.001). Conclusion Total number of polyps, older age, sedentary behavior, abdominal obesity and smoking status contributed to the risk of MPs at surveillance colonoscopy. Patients with grade 1 SPs might require closer surveillance. SPs coexisting with conventional adenoma did not increase the risk of MPs but may increase the risk of developing HSRGPs.