Fundic gland polyps related to diverse aetiologies show subtle morphological differences: a multicentre retrospective study.

AIMS: Fundic gland polyps (FGPs) comprise 66% of all gastric polyps. Although they are usually non-syndromic, they may be associated with various syndromes, including familial adenomatous polyposis (FAP) or gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS). We aimed to evaluate how histological features relate to distinct FGP subtypes. METHODS AND RESULTS: We performed a retrospective analysis of 118 FGPs from 109 patients for the architecture of fundic glands, microcyst lining, parietal cell hyperplasia and surface foveolar epithelial changes. Age, gender and history of FAP or GAPPS were collected. Based on combinations of histological features, three distinct patterns (A, B and C) of FGPs were delineated and correlated to the aetiologies. Non-syndromic FGPs were well-formed polyps composed of disordered fundic glands with intermediate-sized microcysts typically lined by a mixture of oxyntic and mucin-secreting cells (73%). Parietal cell hyperplasia (80%) and foveolar surface hyperplasia (78%) were common. FAP-associated cases demonstrated small microcysts that were predominantly lined by fundic epithelium (77%), with limited parietal cell hyperplasia (27%); foveolar hyperplasia was uncommon. GAPPS-related polyps were the largest, with prominent, mucin-secreting epithelium-lined microcysts (73%). Hyperproliferative aberrant pits were universally present, whereas parietal cell hyperplasia was uncommon. Pattern A was identified in most non-syndromic FGPs (74%) and in a minority of FAP-related FGPs (26%). The majority (82%) of FAP-related FGPs showed pattern B, but only 18% of non-syndromic FGPs did. Pattern C consisted exclusively of GAPPS-associated polyps. CONCLUSIONS: We conclude that, although FGPs share similar histomorphology, subtle differences exist between polyps of different aetiology. In the appropriate clinical setting, the recognition of these variations may help to consider syndromic aetiologies.

Buried Barrett's Esophagus with High-Grade Dysplasia after Radiofrequency Ablation.

Radiofrequency ablation therapy is an effective endoscopic option for the eradication of Barrett's esophagus that appears to reduce the risk of esophageal cancer. A concern associated with this technique is the development of subsquamous/buried intestinal metaplasia, whose clinical relevance and malignant potential have not yet been fully elucidated. Fewer than 20 cases of subsquamous neoplasia after the successful radiofrequency ablation of Barrett's esophagus have been reported to date. Here, we describe a new case of subsquamous neoplasia (high-grade dysplasia) following radiofrequency ablation that was managed with endoscopic resection. Our experience suggests that a meticulous endoscopic inspection prior to and after radiofrequency ablation is fundamental to reduce the risk of buried neoplasia development.