Fundic Gland Mucosa Research Articles

Gastric Epithelial Neoplasm of Fundic-Gland Mucosa Lineage: Showed the Same Genetic Lineage and Ki67 May Help in Their Identification

Abstract Introduction/Objective Gastric epithelial neoplasm of the fundic-gland mucosa lineages (GEN-FGMLs) are rare form of gastric tumors that encompasses oxyntic gland adenoma (OGA), gastric adenocarcinoma of the fundic-gland type (GA-FG), and gastric adenocarcinoma of the fundic-gland mucosa type (GA-FGM). There is no consensus on the clinicopathologica and molecular characteristics of GEN-FGMLs, and misdiagnosis is common because of similarities in symptoms. Methods/Case Report The NGS and immunohistochemical staining were performed on 37 cases diagnosed with GEN-FGMLs with a thorough histological evaluation. Gene alternations were analysed and compared across histological subtypes. we used an artificial intelligence approach for the recognition of the Ki67 immunohistochemistry stained. Results (if a Case Study enter NA) The patient’s ages ranged from 42 to 79 years, with a median age of 60. 17 were male and 20 were female. Morphologically, 19 OGAs, 16 GA-FGs, and two GA-FGMs were identified. Histopathological similarities exist between GEN-FGMLs. The tumors demonstrated well-formed glands, expanding with dense growth patterns comprising pale, blue-grey columnar cells with mild nuclear atypia. The normal gastric pit epithelium covered the entire surface of the OGA and GA-FG, but the dysplasia pit epithelium covered the GA-FGM. Compared with OGA, GA-FG and GA-FGM were more prominent in the macroscopic view (p<0.05) and had larger sizes (p<0.0001). Additionally, GA-FG and GA-FGM exhibited higher Ki67 indices than OGA (p<0.0001). The heterogeneity of mutational signatures, somatic mutations, and copy number variations was revealed across histological subtypes. The top five mutational signatures in OGA were ROS1, CTNNA1, GNAS, BRCA2, and ZFHX3. The top five mutational signatures in GA-FG and GA-FGM were GNAS, MLL3, BRAF, MSH3, and EGFR. GNAS were both found in OGA, GA-FG and GA-FGM. Compared with well-differencent gastric adenocarcinoma, The top five mutational signatures in GEN-FGMLs were GNAS, BRAF, ROS1, MLL3, and MSH3. Recurrently mutated key signaling pathways across tumor types in GEN-FGML were Wnt signaling pathways. Conclusion GEN-FGMLs are a group of well-differentiated gastric tumors with favourable biological behaviours. Compared with OGA, GA-FG and GA-FGM have larger sizes and higher Ki67 proliferation indices, indicating that they play a critical role in the identification of GEN-FGML. GEN-FGMLs showed the same genetic lineage, the Wnt signalling pathway plays a role in the development and progression of GEN-FGMLs.

S2321 Visibility evaluation of Gastric Epithelial Neoplasm of Fundic Gland Mucosa Lineage in a New Image Enhanced Endoscopy; Texture and Color Enhancement Imaging

S2321 Visibility evaluation of Gastric Epithelial Neoplasm of Fundic Gland Mucosa Lineage in a New Image Enhanced Endoscopy; Texture and Color Enhancement Imaging

A case of gastric adenocarcinoma of fundic-gland mucosa type with multiple black spots

A case of gastric adenocarcinoma of fundic-gland mucosa type with multiple black spots

Gastric dysplastic lesions in Helicobacter pylori-naïve stomach: Foveolar-type adenoma and intestinal-type dysplasia.

Reports of Helicobacter pylori (Hp)-naïve gastric neoplasm (HpNGN) cases have been rapidly increasing due to the recent increase in the Hp-naïve population in Japan. Most HpNGNs exhibit the gastric immunophenotype and a low malignant potential regardless of histological type. Especially, foveolar-type gastric adenoma (FGA) and intestinal-type gastric dysplasia (IGD) rarely progress to invasive carcinoma. FGA is a foveolar epithelial neoplasm that occurs in the fundic gland (oxyntic gland) mucosa and is classified as the flat type or raspberry type (FGA-RA). The flat type is a large, whitish flatly elevated lesion while FGA-RA is a small reddish polyp. Genomically, the flat type is characterized by APC and KRAS gene mutations and FGA-RA by a common single nucleotide variant in the KLF4 gene. This KLF4 single-nucleotide variant reportedly induces gastric foveolar epithelial tumorigenesis and activates both cell proliferation and apoptosis, leading to its slow-growing nature. IGD consists of an intestinalized epithelial dysplasia that develops in the pyloric gland mucosa, characterized as a superficial depressed lesion surrounded by raised mucosa showing a gastritis-like appearance. Immunohistochemically, it exhibits an intestinal or gastrointestinal phenotype and, frequently, p53 overexpression. Thus, IGD shows unique characteristics in HpNGNs and a potential multistep tumorigenic process.

Gastric epithelial neoplasm of fundic-gland mucosa lineage: representative of the low atypia differentiated gastric tumor and Ki67 may help in their identification.

Gastric epithelial neoplasm of the fundic-gland mucosa lineages (GEN-FGMLs) are rare forms of gastric tumors that encompass oxyntic gland adenoma (OGA), gastric adenocarcinoma of the fundic-gland type (GA-FG), and gastric adenocarcinoma of the fundic-gland mucosa type (GA-FGM). There is no consensus on the cause, classification, and clinicopathological features of GEN-FGMLs, and misdiagnosis is common because of similarities in symptoms. 37 cases diagnosed with GEN-FGMLs were included in this study. H&E-stained slides were reviewed and clinicopathological parameters were recorded. Immunohistochemical staining was conducted for MUC2, MUC5AC, MUC6, CD10, CD56, synaptophysin, chromograninA, p53, Ki67, pepsinogen-I, H+/K+-ATPase and Desmin. The patients' ages ranged from 42 to 79years, with a median age of 60. 17 were male and 20 were female. Morphologically, 19 OGAs, 16 GA-FGs, and two GA-FGMs were identified. Histopathological similarities exist between OGA, GA-FG, and GA-FGM. The tumors demonstrated well-formed glands, expanding with dense growth patterns comprising pale, blue-grey columnar cells with mild nuclear atypia. These cells resembled fundic gland cells. None of the OGA invaded the submucosal layer. The normal gastric pit epithelium covered the entire surface of the OGA and GA-FG, but the dysplasia pit epithelium covered the GA-FGM. Non-atrophic gastritis was observed in more than half of the background mucosa. All cases were diffusely positive for MUC6 and pepsinogen-I on immunohistochemistry. H+/K+-ATPase staining was negative or showed a scattered pattern in most cases. MUC5AC was expressed on the surface of GA-FGMs. p53 was focally expressed and the Ki67 index was low (1%-20%). Compared with OGA, GA-FG and GA-FGM were more prominent in the macroscopic view (p < 0.05) and had larger sizes (p < 0.0001). Additionally, GA-FG and GA-FGM exhibited higher Ki67 indices than OGA (p < 0.0001). Specimens with Ki-67 proliferation indices >2.5% and size >4.5mm are more likely to be diagnosed with GA-FG and GA-FGM than OGA. GEN-FGMLs are group of well-differentiated gastric tumors with favourable biological behaviours, low cellular atypia, and low proliferation. Immunohistochemistry is critical for confirming diagnosis. Compared with OGA, GA-FG and GA-FGM have larger sizes and higher Ki67 proliferation indices, indicating that they play a critical role in the identification of GEN-FGML. Pathologists and endoscopists should be cautious to prevent misdiagnosis and overtreatment, especially in biopsy specimens.

Endoscopic Diagnosis Strategy of Raspberry-Shaped Gastric Lesion in Helicobacter Pylori-Uninfected Patient.

We aimed to clarify the endoscopic and clinicopathological features of raspberry-shaped gastric lesions (RSGLs) and to establish an endoscopic diagnostic algorithm for RSGLs. We collected RSGLs from an endoscopic database at our hospital between May 2009 and August 2021. All RSGLs were histopathologically classified and compared based on their endoscopic and clinicopathological characteristics. Sixty-five RSGLs in 54 patients were classified into five histopathological types: gastric adenocarcinoma of foveolar type (GA-FV, n = 43), gastric adenocarcinoma of fundic-gland type (GA-FG, n = 2), gastric adenocarcinoma of fundic-gland mucosa type (GA-FGM, n = 4), hyperplastic polyp (HP, n = 12), and proton pump inhibitor-related lesion (PPI-L, n = 4). All RSGLs exhibited polygonal or curved marginal crypt epithelium (MCE). GA-FV lesions had homogenously reddish (95%) and an irregular microvascular (MV) pattern (91%). GA-FG lesions were heterogeneously reddish with a submucosal tumor shape (100%) and had a regular MV pattern (50%). GA-FGM lesions were homogen+ously reddish (75%) and occasionally had a submucosal tumor shape (50%) with an irregular MV pattern (75%). HPs and PPI-Ls were homogeneously reddish (93%), with linear or dotted MCE (81%) and a regular MV pattern (100%). Our diagnostic algorithm for RSGLs constructed using endoscopic features might be useful for the endoscopic differential diagnosis of RSGLs.

Endoscopic Features of Gastric Epithelial Neoplasm of Fundic Gland Mucosa Lineage

The endoscopic features of gastric epithelial neoplasms of fundic gland mucosa lineage (GEN-FGML) have not been well investigated. We aimed to clarify the endoscopic features of GEN-FGML and differences between gastric adenocarcinoma of the fundic gland type (GA-FG) and fundic gland mucosa type (GA-FGM). A total of 62 GEN-FGML lesions, including 52 GA-FG and 10 GA-FGM, were retrospectively analyzed using endoscopic and clinicopathological findings to provide information of diagnostic value using white light imaging (WLI) and magnifying endoscopy with narrow-band imaging (M-NBI). GA-FG frequently presented with a whitish, submucosal tumor (SMT) shape with dilated vessels with branching architecture and background mucosa without atrophic change in WLI, an indistinct demarcation line (DL), dilatation of the crypt opening and intervening part (IP), and microvessels without distinct irregularity in M-NBI. GA-FGM frequently presented as a reddish, elevated lesion in WLI, with a distinct DL, dilatation of the IP, and an irregular microvascular pattern in M-NBI. As for an M-NBI diagnosis, five GA-FGM lesions met the diagnostic criteria for cancer, whereas none of the GA-FG lesions met the same criteria. We highlight the endoscopic features of GEN-FGML, and the differentiation between GA-FG and GA-FGM might be possible by combination of lesion color and morphology in WLI and M-NBI diagnoses.

Sporadic and Familial Adenomatous Polyposis-associated Foveolar-type Adenoma of the Stomach.

Gastric foveolar-type adenoma (FA) is a rare benign neoplasm occurring either sporadically or in patients with familial adenomatous polyposis (FAP). However, the molecular features of FA and the relationship between sporadic and syndromic lesions remain unclear. In this study, we performed clinicopathological, immunohistochemical, and genetic analyses of 18 sporadic and 30 FAP-associated FAs. Most sporadic and FAP-associated FAs were located in the upper or middle third of the stomach, on a background of fundic gland mucosa. Most lesions were low-grade, but 3 lesions had a high-grade component. Sporadic FAs included 2 morphologically distinct subtypes, that is, flat and raspberry-like FAs, which we distinguished based on the endoscopic features. Seven lesions were regarded as flat FAs, appearing as large, slightly elevated lesions and measuring 11 to 87mm in size. Conversely, 10 raspberry-like FAs were small bright-red polyps, measuring 2 to 8mm in size. FAP-associated FAs, particularly larger lesions, exhibited morphologic features resembling flat FAs but varied significantly in size (2 to 103mm). Mutation analysis identified APC and KRAS mutations in all flat FAs but never in raspberry-like FAs. Remarkably, somatic APC and KRAS mutations were also detected in 19 (63%) and 27 (90%) of FAP-associated FAs, respectively. This indicates that they are genetically equivalent to sporadic, flat FAs. This study showed that sporadic FA includes at least 2 morphologically and genetically distinct subtypes: flat and raspberry-like FA. Furthermore, flat FA represents a sporadic counterpart of FAP-associated FA.

Endoscopic submucosal dissection for protruding Helicobacter pylori-negative mucosa-associated lymphoid tissue lymphoma of the stomach: a case report

Gastric mucosa-associated lymphoid tissue (MALT) lymphomas have various endoscopic appearances. We report a case of Helicobacter pylori-negative gastric MALT lymphoma with a protruding morphology similar to that of submucosal tumors. A 51-year-old man with a protruding tumor in the gastric cardia was referred to our hospital. Biopsy specimens showed no malignant epithelial tumors or lymphoid hyperplasia. Endoscopic submucosal dissection was performed and the patient was diagnosed with gastric MALT lymphoma. Lymphoma cells were present in the lamina propria mucosae and the submucosa under the non-atrophic fundic gland mucosa, with a feature of homogenous and monotonous growths, which was speculated to have resulted in a protruding morphology similar to that of submucosal tumors. Endoscopic submucosal dissection can be an alternative diagnostic option for gastric MALT lymphoma when the initial pathological diagnosis based on biopsy specimens is difficult.

Endoscopic Features of Autoimmune Gastritis: Focus on Typical Images and Early Images.

Autoimmune gastritis (AIG) is chronic atrophic gastritis caused by an autoimmune mechanism of unknown etiology and presents with various pathological conditions by causing an achlorhydria state through parietal cell damage. The most characteristic endoscopic finding in AIG is advanced corpus-dominant mucosal atrophy. A recent study that examined several cases in Japan revealed the presence of endoscopic features other than corpus-dominant advanced atrophy. Remnants of oxyntic mucosa and sticky adherent dense mucus were found in ≥30% of cases, and hyperplastic polyps were found in ≥20% of cases. In image-enhanced endoscopy (IEE), white globe appearance (WGA) was observed in 32% of AIG cases. Additionally, some reports have stated that the findings in AIG cases using IEE showed cast-off skin appearance (CSA) and foveola type mucosa; however, a consensus is yet to be achieved. These endoscopic results were found in cases of advanced-stage AIG. There have been few reports concerning early-stage AIG cases. In these few reports, all of the cases were pathologically diagnosed as early AIG. In all of the cases, the pathological findings almost always showed neither parietal cell destruction nor atrophy. Endoscopic findings such as “mosaic pattern with slight swelling of the areae gastricae”, “diffuse reddened and edematous gastric fundic gland mucosa”, and “pseudopolyp-like nodules” may be common characteristics of early images. In such early cases, high antibody titers, no atrophic changes, and few clinical abnormal findings were shown. Endoscopists are expected to update their knowledge regarding AIG diagnosis with the evolution of imaging equipment.

Gastric epithelial neoplasm of fundic-gland mucosa lineage: proposal for a new classification in association with gastric adenocarcinoma of fundic-gland type

BackgroundGastric adenocarcinoma of fundic-gland type (GA-FG) is a rare variant of gastric neoplasia. However, the etiology, classification, and clinicopathological features of gastric epithelial neoplasm of fundic-gland mucosa lineage (GEN-FGML; generic term of GA-FG related neoplasm) are not fully elucidated. We performed a large, multicenter, retrospective study to establish a new classification and clarify the clinicopathological features of GEN-FGML.MethodsOne hundred GEN-FGML lesions in 94 patients were collected from 35 institutions between 2008 and 2019. We designed a new histopathological classification of GEN-FGML using immunohistochemical analysis and analyzed via clinicopathological, immunohistochemical, and genetic evaluation.ResultsGEN-FGML was classified into 3 major types; oxyntic gland adenoma (OGA), GA-FG, and gastric adenocarcinoma of fundic-gland mucosa type (GA-FGM). In addition, GA-FGM was classified into 3 subtypes; Type 1 (organized with exposure type), Type 2 (disorganized with exposure type), and Type 3 (disorganized with non-exposure type). OGA and GA-FG demonstrated low-grade epithelial neoplasm, and GA-FGM should be categorized as an aggressive variant of GEN-FGML that demonstrated high-grade epithelial neoplasm (Type 2 > 1, 3). The frequent presence of GNAS mutation was a characteristic genetic feature of GEN-FGML (7/34, 20.6%; OGA 1/3, 33.3%; GA-FG 3/24, 12.5%; GA-FGM 3/7, 42.9%) in mutation analysis using next-generation sequencing.ConclusionsWe have established a new histopathological classification of GEN-FGML and propose a new lineage of gastric epithelial neoplasm that harbors recurrent GNAS mutation. This classification will be useful to estimate the malignant potential of GEN-FGML and establish an appropriate standard therapeutic approach.

Characteristic endoscopic findings of gastric adenocarcinoma of fundic-gland mucosa type.

Gastric adenocarcinoma of fundic-gland type (GA-FG) was first proposed as a new entity of gastric adenocarcinoma in 2010. Subsequently, gastric adenocarcinoma of fundic-gland mucosa type (GA-FGM) was reported as a subtype of gastric adenocarcinoma. This study aimed to investigate the endoscopic findings of GA-FGM and to evaluate the differences between GA-FGM and GA-FG. This was a single-center retrospective study. Participants were selected from patients with gastric cancer treated at Fukuoka University Chikushi Hospital, between September 2007 and May 2020. Patients histologically diagnosed with GA-FGM or GA-FG were enrolled, and endoscopic findings were analyzed in detail. A total of 12 GA-FGM lesions (12 patients) and 14 GA-FG lesions (13 patients) were analyzed. The two lesion types showed similar features: most lesions were of elevated type, located in the upper stomach, and developed in the stomach without Helicobacter pylori infection. On conventional endoscopy using the dye-spraying method, well-demarcated fine granular areas were observed in 7 GA-FGM lesions (58%) but not in any GA-FG lesions, with a significant difference between the two groups (P = 0.001). Magnifying endoscopy with narrow-band imaging (NBI) showed that 11 GA-FGM lesions (92%) met the diagnostic criteria for cancer according to the vessel plus surface classification system, whereas none of the GA-FG lesions met the same criteria (0%, 0/14) (P = 0.001). Our results suggest that magnifying endoscopy with NBI is a potentially useful method for the diagnosis of GA-FGM.

Gastrointestinal ulceration and gastritis in three wild Temmincks Ground Pangolins (Smutsia temminckii) in captive care in Zambia

Background: Wild rescued pangolins are known to adapt poorly in their captive environment where many die under rehabilitation. Gastrointestinal disease and pneumonia are the most common causes of death in pangolins. However, literature on the pathology of gastric ulcers is rare. Case presentation: The current case report describes the necropsy and histopathological evaluation of three Temminck’s pangolins that died under rehabilitation in Lusaka, Zambia. Grossly, gastric ulcerations of the fundic gland mucosae were seen in the stomachs. Inflammatory cells and erosions of fundic gastric gland mucosa were seen on histopathology. The morphological diagnosis of gastric ulceration with gastritis was attributed to stress and inappropriate diet. Conclusions: The findings are expected to increase knowledge in pangolin diseases and thus improve the conservation efforts to save the pangolin species from extinction.

Inflammatory Cell Numbers in the Stomach of Japanese Subjects with Endoscopically Normal Mucosa without Helicobacter pylori Infection

Introduction: Since inflammatory cells, such as lymphocytes and plasma cells, normally inhabit the stomach, the border between normal and mild inflammation is difficult to visually determine using the updated Sydney system scale of gastritis. Additionally, eosinophils in the gastric mucosa must be counted to diagnose eosinophilic gastritis. We aimed to determine the normal number of inflammatory cells in patients with endoscopically normal mucosa and without Helicobacter pylori infections. Methods: We assessed patients aged 20–79 years, who had undergone upper gastrointestinal endoscopy at Kawasaki Medical School Hospital between January 2010 and December 2014. Inflammatory cells were counted in 1,000 μm² fields of pyloric and fundic gland mucosal biopsy specimens. We finally included 325 (male, n = 141; female, n = 184; average age = 49.3 years) patients without inflammation who had H. pylori-negative endoscopic results and negative histological findings interpreted based on the updated Sydney System and the Kyoto classification of gastritis. Results: The average numbers of nucleated cells were 83.3 ± 14.2 and 65.4 ± 12.6/mm² in the pyloric and fundic gland mucosae, respectively. Inflammatory cells were significantly more abundant in the pyloric mucosa than in the fundic gland mucosa (p < 0.05). Age and sex distribution did not significantly differ. Eosinophils were absent or scanty in the gastric mucosae of both glands in all patients. Conclusion: We determined the absolute values of inflammatory cells, including eosinophils, in normal mucosae of pyloric and fundic glands. These findings could be important in defining gastric mucosal inflammation, including eosinophilic gastritis diagnosis.

A case of early autoimmune gastritis with characteristic endoscopic findings

Significant atrophic gastritis in the fundic gland region is a well-known endoscopic finding observed in autoimmune gastritis (AIG). The endoscopic features of early AIG have not been reported. Iron deficiency, vitamin B12 deficiency, anemia, or neurological symptoms may not be observed in the early stages of AIG, and it may thus be difficult to diagnose early AIG based on clinical findings. We treated a 50-year-old Japanese female whose condition was suspected to be early AIG. The endoscopic findings showed normal gastric pyloric gland mucosa, and diffuse reddened and edematous gastric fundic gland mucosa. Pathologically, local infiltration of lymphocytes and decrease of parietal cells was present in a deep part of the gastric fundic gland mucosa. Blood tests showed that the titer of parietal cell antibody (PCA) was 1:320 and the gastrin level was 820 pg/ml. We determined that the patient had AIG because she also had Hashimoto’s disease, the PCA titer was high, the serum gastrin level was slightly increased, and inflammation was observed only in the gastric body on the endoscopic images. To the best of our knowledge, this is the first case report of endoscopic findings that suggest early AIG, before atrophic changes were observed.

Clinicopathological and Endoscopic Features of Raspberry-Shaped Gastric Cancer in Helicobacter pylori-Uninfected Patients

Background: Gastric adenocarcinoma of foveolar type (GA-FV) is a raspberry-shaped gastric cancer (RSGC) and garners much attention as H. pylori (Hp)-uninfected gastric cancer. However, the classification and clinicopathological and endoscopic features of RSGCs in Hp-uninfected patients are poorly defined. We designed a new histopathological classification of RSGC and compared them via endoscopic and clinicopathological characteristics. Summary: From 996 patients with early gastric cancers resected by endoscopy in our hospital, we studied 24 RSGC lesions from 21 (2.4%) Hp-uninfected patients. RSGCs were classified into 3 histological types as follows: GA-FV (n = 19), gastric adenocarcinoma of fundic gland type (GA-FG, n = 2), and gastric adenocarcinoma of fundic gland mucosa type (GA-FGM, n = 3). Most of the lesions were found at the greater curvature of the upper or middle third of the stomach. GA-FV lesions were homogeneously reddish and frequently accompanied with a whitish area around the tumor and an irregular microvascular (MV) pattern; these features were confirmed histopathologically by the presence of homogeneous neoplastic foveolar epithelium with foveolar hyperplasia around the tumors. GA-FG lesions might be heterogeneously reddish with a submucosal tumor shape and regular MV pattern; these were confirmed by the presence of covered or mixed nonneoplastic epithelium on deeper regions of tumors. GA-FGM lesions might be homogeneously reddish and occasionally had a submucosal tumor shape and irregular MV pattern; these were confirmed by the presence of homogeneous neoplastic foveolar epithelium on deeper regions of the tumors. Key Messages: RSGCs in Hp-uninfected patients are classified into 3 histopathological types. For accurate diagnosis of RSGCs, it may be necessary to fully understand endoscopic features of these lesions based on these histological characteristics and to take a precise biopsy.

S2920 Oxyntic Gland Adenoma of the Stomach; A Case Study of an Under-Reported Entity

INTRODUCTION: Oxyntic gland adenoma (OGA), also known as gastric adenocarcinoma with chief cell predominance is a rare entity, with incidence and prevalence data unknown. Given its rarity, we present a case of OGA incidentally found on EGD in a patient with complaints of dyspepsia. CASE DESCRIPTION/METHODS: A 58-year-old female with a history of smoking presented to the GI clinic for colorectal cancer screening. On presentation, ROS was only notable for dyspepsia not related to food intake or exercise. Her physical exam was unremarkable. She was scheduled for both colonoscopy for cancer screening and EGD for evaluation of dyspepsia. Colonoscopy was negative for cancer. EGD showed a solitary papule in the gastric fundus (Figure 1). The papule was raised, pale/white in color, 4 mm in diameter, and had a highly vascularized base. The papule was completely excised with cold biopsy forceps. Pathological analysis was notable for a completely resected papule without evidence of intestinal metaplasia. Further analysis revealed that the papule was composed of fundic gland mucosa, with chief cells predominating and low-grade cytologic features consistent with an oxyntic gland adenoma (Figures 2 and 3). DISCUSSION: OGA is characterized as a benign, solitary, polypoid growth, usually located in the fundus and less often in the cardia of the stomach. Prior studies have explored the histological patterns of these polyps and have defined them as either chief cell predominant, or a mixture of chief and parietal cells. The nomenclature is disputed as multiple names have been proposed for a similar histological description including: chief cell hyperplasia, chief cell hamartoma, and oxyntic gland adenocarcinoma with chief cell predominance. The last is a misnomer as these polyps lack atypical features such as mucous gland cells or foveolar epithelium. Additionally, they do not invade through the submucosa, as seen in other carcinomas. As some pathologists and gastroenterologists are still unfamiliar with the clinical and histological presentation of OGA, we highlight this rare finding for further discussion of its proper nomenclature and a better understanding of etiology, incidence, and prevalence in the United States.Figure 1.: Endoscopic View of Polyp (Encompassed in Black Circle).Figure 2.: Full Slice of Polyp revealing Fundic Type Mucosa Containing Oxyntic Gland Adenoma.Figure 3.: 200x Zoomed view of Fundic Mucosa with Oxyntic Gland Adenoma (Black Arrow points to normal Oxyntic gland and White arrows point to Oxyntic gland with Chief cell predominance).

Oxyntic gland neoplasm of the stomach: expanding the spectrum and proposal of terminology.

Gastric neoplasms exhibiting oxyntic gland differentiation typically are composed of cells with mild cytonuclear atypia differentiating to chief cells and to a lesser extent, parietal cells. Such tumors with atypical features have been reported also and terminology for this entity remains a matter of considerable debate. We analyzed and classified 26 tumors as oxyntic gland neoplasms within mucosa (group A, eight tumors) and with submucosal invasion. The latter was divided further into those with typical histologic features (group B, 14 tumors) and atypical features, including high-grade nuclear or architectural abnormality and presence of atypical cellular differentiation (group C, four tumors). Groups A and B tumors shared similar histologic features displaying either a chief cell predominant pattern characterized by monotonous chief cell proliferation, or a well-differentiated mixed cell pattern showing admixture of chief and parietal cells resembling fundic gland. In addition, group C tumors displayed atypical cellular differentiation, including mucous neck cell and foveolar epithelium. Moderate or even marked cytological atypia was noted in group C, whereas it was usually mild in the other groups except for three group B tumors with focal moderate atypia. More than 1000 μm submucosal invasion and lymphovascular invasions were recognized only in group C. Mutation analyses identified KRAS mutation in one group C tumor as well as GNAS mutation in in one group A and group B tumors. Intramucosal tumors appear to behave biologically benign and should be classified as "oxyntic gland adenoma". Those with submucosal invasion also have low malignant potential; however, a subset will have atypical features associated with aggressive histologic features and should be designated as "adenocarcinoma of fundic gland type". Especially, we suggest "adenocarcinoma of fundic gland mucosa type" for tumors with submucosal invasion exhibiting atypical cellular differentiation, because the feature is likely to be a sign of aggressive phenotype.

A case of gastric adenocarcinoma of the fundic gland mucosa type treated by endoscopic submucosal dissection after eight-year observation

A case of gastric adenocarcinoma of the fundic gland mucosa type treated by endoscopic submucosal dissection after eight-year observation

Linked color imaging improves endoscopic diagnosis of active Helicobacter pylori infection.

Background and study aims: Linked color imaging (LCI) is a new image-enhanced endoscopy technique using a laser light source to enhance slight differences in mucosal color. The aim of this study was to compare the usefulness of LCI and conventional white light imaging (WLI) endoscopy for diagnosing Helicobacter pylori (H. pylori). Patients and methods: We retrospectively analyzed images from 60 patients examined with WLI and LCI endoscopy between October 2013 and May 2014. Thirty patients had H. pylori infections, and other thirty patients tested negative for H. pylori after eradication therapy. Four endoscopists evaluated the 2 types of images to determine which was better at facilitating a diagnosis of H. pylori infection. Results: H. pylori infection was identified with LCI by enhancing the red appearance of the fundic gland mucosa. The accuracy, sensitivity, and specificity for diagnosing H. pylori infection using WLI were 74.2 %, 81.7 %, and 66.7 %, respectively, while those for LCI were 85.8 %, 93.3 %, and 78.3 %, respectively. Thus, the accuracy and sensitivity for LCI were significantly higher than those for WLI (P = 0.002 and P = 0.011, respectively). The kappa values for the inter- and intraobserver variability among the 4 endoscopists were higher for LCI than for WLI. Conclusions: H. pylori infection can be identified by enhancing endoscopic images of the diffuse redness of the fundic gland using LCI. LCI is a novel image-enhanced endoscopy and is more useful for diagnosing H. pylori infection than is WLI.