Deep learning for multiclass tumor cell detection in histopathology slides of hereditary diffuse gastric cancer.

Hereditary diffuse gastric cancer (HDGC) is a rare condition where early tumor detection is challenging due to diffuse infiltration and tumor heterogeneity. Accurate identification of DGC cells is essential for understanding tumor behavior. This study aimed to develop deep learning models to automatically detect key tumor cell types-typical and atypical signet ring cells and non-signet ring tumor cells-in H&E-stained digital pathology slides from HDGC patients.

Pathologist-Read vs AI-Driven Assessment of Tumor-Infiltrating Lymphocytes in Melanoma.

Importance: Tumor-infiltrating lymphocytes (TILs) are a provocative biomarker in melanoma, influencing diagnosis, prognosis, and immunotherapy outcomes; however, traditional pathologist-read TIL assessment on hematoxylin and eosin-stained slides is prone to interobserver variability, leading to inconsistent clinical decisions. Therefore, development of newer TIL scoring approaches that produce more reliable and consistent readouts is important.

Objective: To evaluate the analytical and clinical validity of a machine learning algorithm for TIL quantification in melanoma compared with traditional pathologist-read methods.

Cost-utility and clinical impact of endoscopic screening for esophageal and gastric neoplasia in patients with head and neck neoplasms.

Objective: Patients with head and neck neoplasms (HNN) are at an increased risk of esophageal neoplasia (EN) and gastric neoplasia (GN). We aimed to assess the clinical impact and cost-utility of endoscopic screening in this population in the Western setting.

Methods: In this single-center study HNN patients eligible for curative treatment underwent screening esophagogastroduodenoscopy.

Spatial Analysis of Hereditary Diffuse Gastric Cancer Reveals Indolent Phenotype of Signet Ring Cell Precursors.

Unlabelled: Germline CDH1 loss-of-function mutations are causally linked to an increased lifetime risk of diffuse gastric cancer (DGC). Early, multifocal signet ring cell (SRC) lesions are ubiquitous among CDH1 variant carriers, yet only a subset of patients will develop advanced DGC. A multiomic analysis was performed to establish the molecular phenotype of early SRC lesions and how they differ from advanced DGC using 20 samples from human total gastrectomy specimens of germline CDH1 variant carriers.

Epstein-Barr virus status drives morphological and molecular intra-tumour heterogeneity in gastric cancer: insights from a case report and literature review.

This case report describes a rare case of bi-phenotypic gastric cancer with two distinct, but clonally related, histological components. The first component, associated with Epstein-Barr virus (EBV) infection, exhibited the morphological features of gastric carcinoma with lymphoid stroma, suggesting that EBV, as an effective immunogenic factor, may trigger a prominent immune response within the tumour microenvironment. The second component, which was EBV-negative, displayed tubular/papillary morphology and features of increased biological aggressiveness, such as high-grade areas and lymphatic invasion.

Underwater Endoscopic Mucosal Resection Vs Conventional Endoscopic Mucosal Resection for Superficial Nonampullary Duodenal Epithelial Tumors in the Western Setting.

Background & Aims: Conventional endoscopic mucosal resection (C-EMR) is established as the primary treatment modality for superficial nonampullary duodenal epithelial tumors (SNADETs), but recently underwater endoscopic mucosal resection (U-EMR) has emerged as a potential alternative. The majority of previous studies focused on Asian populations and small lesions (≤20 mm). We aimed to compare the efficacy and outcomes of U-EMR vs C-EMR for SNADETs in a Western setting.

Fibrosis-related Transcriptome Unveils a Distinctive Remodelling Matrix Pattern in Penetrating Ileal Crohn's Disease.

Background And Aims: Stricturing [B2] and penetrating [B3] ileal Crohn's disease have been reported to present similar levels of histopathological transmural fibrosis. This study aimed to compare the fibrosis-related transcriptomic profiles of penetrating and stricturing ileal Crohn's disease.

Methods: Using Nanostring technology and comparative bioinformatics, we analysed the expression of 787 fibrosis-related genes in 36 ileal surgical specimens, 12 B2 and 24 B3, the latter including 12 cases with associated stricture[s] [B3s] and 12 without [B3o].

HER2 and PD-L1 Expression in Gastric and Gastroesophageal Junction Cancer: Insights for Combinatorial Targeting Approaches.

Gastric and gastroesophageal junction adenocarcinomas (GA/GEJA) are associated with a poor prognosis, primarily due to late disease diagnosis. Human Epidermal Growth Factor Receptor 2 (HER2) overexpression and programmed death-ligand 1 (PD-L1) expression are important biomarkers for treatment selection in locally advanced unresectable and metastatic GA/GEJA, and there is increasing interest in their role in earlier stages of disease. In this study, we aimed to evaluate HER2 and PD-L1 expression in a curative-intent GA/GEJA cohort to describe their expression patterns and analyze the association between HER2 expression and clinicopathological features.

Morphologic Heterogeneity of Carcinoma with Signet Ring Cell Features at Different Primary Sites.

Introduction: Signet ring cells (SRCs) may be observed in carcinomas from multiple primary sites. Elucidating unknown primaries from metastases with SRCs represents a diagnostic challenge. This study examined morphologic characteristics of adenocarcinomas with SRCs from stablished primary sites and described objective features, which can aid in identifying the site of origin.

Gastric Polyps in Familial Adenomatous Polyposis Portuguese Patients: The First Western Cohort with Asian Features.

Introduction: Chronic atrophic gastritis may contribute to gastric polyps (GP) phenotype in familial adenomatous polyposis (FAP). Considering the high prevalence of Helicobacter pylori (HP) infection in Portugal, we aim to characterize GP in a series of Portuguese patients.

Methods: In a retrospectively selected series of 53 FAP patients, clinical data and histopathological features of GP and background gastric mucosa were studied.

Predicting residual neoplasia after a non-curative gastric ESD: validation and modification of the eCura system in the Western setting: the W-eCura score.

Objective: To evaluate the risk factors for lymph node metastasis (LNM) after a non-curative (NC) gastric endoscopic submucosal dissection (ESD) and to validate and eventually refine the eCura scoring system in the Western setting. Also, to assess the rate and risk factors for parietal residual disease.

Design: Retrospective multicentre multinational study of prospectively collected registries from 19 Western centres.

3D Chromatin Architecture Re-Wiring at the Loci Contributes to E-Cadherin to P-Cadherin Expression Switch in Gastric Cancer.

Cadherins are cell-cell adhesion molecules, fundamental for cell architecture and polarity. E-cadherin to P-cadherin switch can rescue adherens junctions in epithelial tumours. Herein, we disclose a mechanism for E-cadherin to P-cadherin switch in gastric cancers.

Role of Endoscopic Biopsies and Morphologic Features in Predicting Microsatellite Instability Status in Gastric Cancer: A Multicenter Comparative Study of Endoscopic Biopsies and Surgical Specimens.

Evaluation of mismatch repair (MMR) protein and microsatellite instability (MSI) status plays a pivotal role in the management of gastric cancer (GC) patients. In this study, we aimed to evaluate the accuracy of gastric endoscopic biopsies (EBs) in predicting MMR/MSI status and to uncover histopathologic features associated with MSI. A multicentric series of 140 GCs was collected retrospectively, in which EB and matched surgical specimens (SSs) were available.

Performance of Immunohistochemical and Molecular Methods in Detecting Microsatellite Instability in Gastric Cancer: A Multicenter Study.

Introduction: Microsatellite instability (MSI) is an important prognostic molecular biomarker for gastric cancer (GC). MSI status may be detected by immunohistochemistry (IHC) for mismatch repair (MMR) proteins and polymerase chain reaction (PCR). Idylla™ MSI assay has not been validated for GC but may prove to be a valid alternative.

DOES NEOADJUVANT CHEMORADIOTHERAPY FOR ESOPHAGEAL AND GASTROESOPHAGEAL JUNCTION CANCER PATIENTS AFFECT POSTOPERATIVE OUTCOMES? A STUDY USING THE BECKER TUMOR REGRESSION GRADE SYSTEM AND LYMPH NODE REGRESSION.

Background: The effect of neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced esophageal cancer can be determined by assessing the Becker tumor regression grade in the primary tumor, as well as in lymph nodes.

Aims: The aim of this study was to investigate the anatomopathological changes caused by neoadjuvant chemoradiotherapy and their impact on clinical parameters. Specifically, we analyzed the Becker tumor regression grade, lymph node status, and regression changes and evaluated their association with the Clavien-Dindo classification of surgical complications and overall patient survival.

EBV and MSI Status in Gastric Cancer: Does It Matter?

We investigated the impactof microsatellite instability (MSI) and Epstein-Barr virus (EBV) status in gastric cancer (GC), regarding response to perioperative chemotherapy (POPChT), overall survival (OS), and progression-free survival (PFS). We included 137 cases of operated GC, 51 of which were submitted to POPChT. MSI status was determined by multiplex PCR and EBV status by EBV-encoded RNA in situ hybridization.

A practical approach for PD-L1 evaluation in gastroesophageal cancer.

PD-L1 is an established predictive immunohistochemical biomarker of response to immune checkpoint inhibitors. At present, PD-L1 is routinely assessed on biopsy samples of advanced gastroesophageal cancer patients before initiating first-line treatment. However, PD-L1 is still a suboptimal biomarker, due to changing cut-off values and scoring systems, interobserver and interlaboratory variability.

PD-L1 evaluation in the gastrointestinal tract: from biological rationale to its clinical application.

Immune-checkpoint inhibitors targeting the PD-1/PD-L1 axis have brought significant clinical benefit in many solid cancer types, including gastrointestinal malignancies. However, it has been estimated that only 20-40% of patients respond to treatment. The pattern of expression and potential predictive value of PD-L1 as an immunohistochemical biomarker has been extensively studied in gastrointestinal neoplasms.

Activation of Laminin γ2 by Helicobacter pylori Promotes Invasion and Survival of Gastric Cancer Cells With E-Cadherin Defects.

Background: Helicobacter pylori infection induces cellular phenotypes relevant for cancer progression, namely cell motility and invasion. We hypothesized that the extracellular matrix (ECM) could be involved in these deleterious effects.

Methods: Microarrays were used to uncover ECM interactors in cells infected with H.

Acute gastrointestinal graft-versus-host disease with cytomegalovirus and Epstein-Barr virus superinfection in a patient with COVID-19.

A 60-year-old female was diagnosed with acute myeloid leukemia. After initial remission with chemotherapy, she relapsed and underwent allogeneic hematopoietic stem cell transplantation (HSCT). Two months later, she presented to emergency department with watery diarrhea, abdominal pain and fever.

Primary small bowel follicular lymphoma: the role of balloon-assisted enteroscopy in diagnosis and follow-up.

An asymptomatic 38-year-old male with no significant previous medical history performed routine laboratory studies that revealed iron-deficiency anemia. Esophagogastroduodenoscopy and colonoscopy were unremarkable and he undergone videocapsule endoscopy that revealed multiple small polyps along jejunum and ileum. Double-balloon enteroscopy confirmed the presence of scattered small whitish nodules and small polyps carpeting segments of jejunal mucosal and sometimes forming conglomerates with a nodular appearance.

Gastric cancer genetic predisposition and clinical presentations: Established heritable causes and potential candidate genes.

Tumour risk syndromes (TRS) are characterized by an increased risk of early-onset cancers in a familial context. High cancer risk is mostly driven by loss-of-function variants in a single cancer-associated gene. Presently, predisposition to diffuse gastric cancer (DGC) is explained by CDH1 and CTNNA1 pathogenic and likely pathogenic variants (P/LP), causing Hereditary Diffuse Gastric Cancer (HDGC); while APC promoter 1B single nucleotide variants predispose to Gastric Adenocarcinoma and Proximal Polyposis of the Stomach (GAPPS).