Characteristics of Clinically Significant Hyperplastic Polyps: Distinctions Between Microvesicular and Goblet Cell-Rich Types

Background: Clinically significant serrated polyps (CSSPs) are defined as sessile serrated lesions (SSLs), SSLs with dysplasia, traditional serrated adenomas (TSAs), hyperplastic polyps (HPs) ≥ 10 mm, and HPs ≥ 6 mm in the proximal colon. HPs are further classified as microvesicular HPs (MVHPs) and goblet cell-rich HPs (GCHPs). Among CSSPs, HPs were categorized into clinically significant MVHPs (CS-MVHPs) and clinically significant GCHPs (CS-GCHPs). This study compares the characteristics of CS-MVHPs, CS-GCHPs, and SSLs. Methods: This study included patients who underwent colonoscopy at the Toyoshima Endoscopy Clinic between March 2021 and April 2024. Lesions diagnosed as adenomas or CSSPs were removed. Age, sex, number of polyps, detection rate, and polyp size were compared among CS-MVHPs, CS-GCHPs, and SSLs. Results: In total, 14 065 patients were enrolled. The detection rates for CS-MVHPs, CS-GCHPs, and SSLs were 5.24%, 1.22%, and 6.36%, respectively. Patients with CS-MVHPs or SSLs were significantly younger and more often female than those with CS-GCHPs. The mean sizes of CS-MVHPs and SSLs were significantly larger than that of CS-GCHPs. The detection rate of CS-GCHPs increased with age, whereas the detection rates of CS-MVHPs and SSLs did not show a similar trend. Conclusions: Compared with CS-GCHPs, CS-MVHPs were larger, more frequent, and more likely to be found in younger patients and females. The characteristics of CS-MVHPs are similar to those of SSLs, supporting the hypothesis that CS-MVHPs are precursors of SSLs.