# Dysplastic Transformation in Sporadic Fundic Gland Polyps: Prevalence, Clinical and Endoscopic Characteristics in an Asian Cohort

## TL;DR

This study examines how often benign stomach polyps become precancerous in an Asian population, finding that it is very rare and identifying features that may help doctors detect these cases.

## Contribution

The study provides the first detailed analysis of dysplastic fundic gland polyps in an Asian cohort, highlighting clinical and endoscopic features for early detection.

## Key findings

- Sporadic dysplastic fundic gland polyps occurred in 0.059% of patients in a 25-year Taiwanese cohort.
- Dysplastic polyps were typically small, multiple, and located in the gastric body/fundus, with subtle endoscopic warning signs.
- Low-grade dysplasia was more common than high-grade, and no cases were associated with Helicobacter pylori infection.

## Abstract

Fundic gland polyps (FGPs) are common gastric polyps and are usually benign, but they can rarely develop dysplasia, a precancerous epithelial change. Because data from Asian populations are limited, we reviewed a 25-year single-center pathology archive in Taiwan (2000–2024). Among 35,806 unique patients with histologically confirmed FGPs, we identified 25 cases of FGPs with dysplasia. Most were sporadic (21/25), corresponding to a patient-level prevalence of 0.059%. Sporadic cases occurred at a median age of 48 years and were slightly more common in women (57.1%). Low-grade dysplasia predominated (90.5%). One-third of patients had documented proton pump inhibitor exposure before diagnosis (median documented duration: 36 months), whereas none had documented current Helicobacter pylori infection at the index evaluation. Endoscopically, dysplastic FGPs were typically small (median: 0.5 cm), often multiple, sessile, and located in the gastric body and/or fundus, frequently detected during health examinations. Subtle warning signs included erythema, surface irregularity, or focal erosion; when narrow-band imaging was used, irregular or dilated microvascular patterns were described. These clinical and endoscopic characteristics may help clinicians recognize when an FGP warrants targeted biopsy or complete endoscopic resection, while highlighting the need for prospective studies with appropriate comparator groups.

Background/Objectives: Fundic gland polyps (FGPs) are the most common type of gastric polyp and have increased in prevalence in the proton pump inhibitor (PPI) era. Although traditionally considered benign, dysplasia has been described in both syndromic and sporadic FGPs; data from Asian cohorts remain limited. We evaluated the prevalence of FGPs with dysplasia (FGPD) and described associated clinical and endoscopic features in a Taiwanese tertiary-care cohort. Methods: We retrospectively searched institutional pathology archives for all gastric biopsy or polypectomy specimens diagnosed as FGP between January 2000 and December 2024 and mapped these specimens to unique patients using medical record numbers. Candidate dysplastic cases underwent slide review by gastrointestinal pathologists to confirm FGPD and grade dysplasia as low- or high-grade according to standard gastric dysplasia criteria. Cases were classified as syndromic if a hereditary polyposis syndrome was documented; otherwise, they were classified as sporadic. Clinical and endoscopic variables were abstracted from electronic medical records. Patient-level prevalence estimates among patients with FGP are reported with exact 95% confidence intervals (CIs). Results: Among 35,806 unique patients with histologically confirmed FGP, 25 FGPD cases were confirmed (21 sporadic, 4 syndromic). The patient-level prevalence of sporadic FGPD was 0.059% (21/35,806; 95% CI: 0.036–0.090%). Among sporadic cases, dysplasia was low-grade in 19 (90.5%) and high-grade in 2 (9.5%). Sporadic cases occurred at a median age of 48 years (interquartile range [IQR]: 37–63.5 years), and 57.1% were female. Documented PPI exposure before the index FGPD endoscopy was present in 33.3% of patients (median documented duration: 36 months [IQR: 12–125]). No case had documented current Helicobacter pylori infection at the index evaluation. Endoscopically, sporadic FGPDs were commonly multiple, sessile, located in the gastric body/fundus, and small (median size: 0.5 cm [IQR: 0.3–0.575]). Conclusions: Sporadic FGPD was exceedingly rare in this 25-year Taiwanese cohort and was predominantly low-grade. Although typically small and body/fundus-predominant, FGPs with erythema or surface irregularity—particularly with irregular microvascular patterns on narrow-band imaging—should prompt histologic assessment to exclude dysplasia.