Endoscopic Biopsy Specimens Research Articles

Disseminated proliferative mesocestoidosis caused by Mesocestoides vogae (Cestoda: Cyclophyllidae) in a French bulldog in Japan.

This report describes a case of disseminated proliferative mesocestoidosis in a French bulldog from Aichi, Japan. In July 2023, the dog presented with chronic enteritis, and histological examination of the endoscopic biopsy specimen revealed parasites with suckers. Three months later, numerous tetrathyridia were detected in the inguinal mass. In April 2024, polymorphic tetrathyridia were detected on the visceral organs. These parasites were identified as Mesocestoides vogae (Cyclophylidea: Mesocestoididae) based on morphological features and sequence analyses. In Japan, M. vogae has only been reported in domestic dogs, with five cases of intestinal infection and one case of abdominal infection. This report is the first case of both intestinal and extraintestinal infections in the westernmost region of Japan.

Neoadjuvant chemoradiotherapy up-regulates PD-L1 in radioresistant colorectal cancer.

Combining radiotherapy (RT) with immune checkpoint inhibitors (ICIs) is a promising strategy that can enhance the therapeutic efficacy of ICIs. However, little is known about RT-induced changes in the expression of immune checkpoints, such as PD-L1, and their clinical implications in colorectal cancer (CRC). This study aimed to investigate the association between responsiveness to RT and changes in PD-L1 expression in human CRC tissue and cell lines. Tissue specimens from preoperative biopsy via sigmoidoscopy and surgical resection were obtained from 24 patients with locally advanced rectal cancer (LARC) who underwent neoadjuvant chemoradiation therapy (CRT) between August 2016 and December 2017. Immunohistochemistry for PD-L1 in formalin-fixed paraffin-embedded tissue was performed from the endoscopic biopsy and surgical specimens. RNA sequencing was performed using 11 pairs of human LARC tissues before and after irradiation. After exposing human CRC cells to radiation, we investigated changes in the expression levels of PD-L1 and its regulatory signaling pathways. Patients were classified by tumor regression grade into responders (grade 2; 9 patients, 37.5%) and non-responders (grades 3, 4, or 5; 15 patients, 62.5%). In the non-responder group, 13 patients had low PD-L1 expression, but neoadjuvant CRT increased PD-L1 expression in 7 patients (53.9%) (McNemar's test, p=0.034). CRT up-regulated PD-L1 in non-responder LARC tissues. Similarly, radiation increased PD-L1 in radioresistant DLD-1 cells more than in radiosensitive HCT116 cells, also affecting PD-L1-regulating genes and immune checkpoints in CRC cells. Conventional fractionated radiation treatment further increased PD-L1 in DLD-1 cells compared to HCT116 cells. This study demonstrated that radiation induces an increase in PD-L1 expression, which is more pronounced in radioresistant CRC, proving the theoretical framework for a combined treatment strategy with a PD-L1 blockade for locally advanced rectal cancer.

Establishment and Characterization of Patient-Derived Intestinal Organoids from Pediatric Crohn's Disease Patients.

This study aimed to establish and characterize patient-derived intestinal organoids (PDOs) from children with Crohn's disease (CD). To generate PDOs, endoscopic biopsy specimens were obtained from non-inflamed duodenal bulbs of normal controls and CD patients. To verify the presence of PDOs, histological staining and quantitative reverse transcription polymerase chain reaction (RT-qPCR) analyses were performed. PDOs were successfully established in normal controls (n=2) and CD patients (n=2). Hematoxylin and eosin staining of formalin-fixed, paraffin-embedded PDO sections revealed crypt and villus structures, whereas immunofluorescence staining with EpCAM and DAPI confirmed the epithelial-specific architecture of the PDOs. RT-qPCR results revealed a significant increase in Lgr5, Si, and Chga gene expression and a decrease in Olfm4 and Muc2 expression in CD patients compared to normal controls, suggesting altered stem cell activity and mucosal barrier function (p<0.05). We successfully established and characterized PDOs in children with CD, providing a valuable tool for understanding the pathophysiology of the disease and evaluating potential therapeutic approaches. The differential gene expression of PDOs in CD patients might be caused by the complex interplay between epithelial adaptation and inflammation in the intestinal epithelium.

A Case of Superficial Esophageal Neuroendocrine Carcinoma with Marked Morphological Changes in a Short Period.

A de novo whitish subepithelial lesion (SEL) with irregular vascular hyperplasia was detected in the lower thoracic esophagus during endoscopic surveillance. Special types of esophageal cancer were suspected; however, endoscopic biopsy specimens were inadequate for a diagnosis. Ten days later, endoscopic ultrasound showed a 7-mm homogeneously hypoechoic round mass in the submucosa, and a biopsy confirmed a histological diagnosis of esophageal neuroendocrine carcinoma (eNEC). Based on the clinical diagnosis of cT2N0M0, subtotal esophagectomy followed by adjuvant chemotherapy was performed immediately after endoscopic reexamination revealing a 20-mm reddish SMT. We herein report the marked changes in endoscopic findings of eNEC within 1.5 months.

Biomarker Study for Selecting Neoadjuvant Chemotherapy Regimens Based on Prognostic Prediction Using Gastric Cancer Biopsy Specimens from a Phase II Randomized Controlled Trial.

The randomized phase II COMPASS trial revealed that neither the regimen nor the number of courses of preoperative neoadjuvant chemotherapy (NAC) for locally advanced gastric cancer (GC) significantly influence overall survival (OS). However, the impact of NAC regimens on OS may vary from patient to patient. The aim of this study was to identify biomarkers that can predict more appropriate individualized NAC regimens for improved prognosis using biopsy specimens from the COMPASS trial. RNA was extracted from endoscopic biopsy specimens of primary tumors obtained prior to NAC and real-time PCR analysis of 127 genes was conducted to identify those significantly affecting survival in the context of specific NAC regimens. THBS1, MSI1, and IGF2BP3 were identified as significant factors for stratifying survival among different NAC regimens, with statistically significantly interaction p values. Immunohistochemical analysis confirmed that the protein levels of THBS1, MSI1, and IGF2BP3 strongly correlated with their gene expression levels, validating these proteins as reliable biomarkers. This study effectively identified THBS1, MSI1, and IGF2BP3 as promising biomarkers for personalizing NAC regimens in patients with locally advanced GC. By tailoring NAC based on these biomarkers, it is possible to enhance survival outcomes and advance personalized treatment strategies. The findings underscore the potential for incorporating biomarker-guided approaches into clinical trials, aiming to refine and optimize NAC regimens for improved patient-specific treatment efficacy.

Phosphoproteomic subtyping of gastric cancer reveals dynamic transformation with chemotherapy and guides targeted cancer treatment

There are only a few effective molecular targeted agents for advanced unresectable or recurrent advanced gastric cancer (AGC), which has a poor prognosis with a median survival time of less than 14months. Focusing on phosphorylation signaling in cancer cells, we have been developing deep phosphoproteome analysis from minute endoscopic biopsy specimens frozen within 20s of collection. Phosphoproteomic analysis of 127 fresh-frozen endoscopic biopsy samples from untreated patients with AGC revealed three subtypes reflecting different cellular signaling statuses. Subsequent serial biopsy analysis has revealed the dynamic mesenchymal transitions within cancer cells, along with the concomitant rewiring of the kinome network, ultimately resulting in the conversion to the epithelial-mesenchymal transition (EMT) subtype throughout treatment. We present our investigation of intracellular signaling related to the EMT in gastric cancer and propose therapeutic approaches targeting AXL. This study also provides a wealth of resources for the future development of treatments and biomarkers for AGC.

Decreased CD3+CD56+ Natural Killer T Lymphocytes and Increased Human Leukocyte Antigen-DR+ Cells in the Inflamed Area of Pouchitis in Ulcerative Colitis Patients.

Pouchitis is an inflammatory condition that affects the ileal pouch during ileal pouch-anal anastomosis surgery. Despite its clinical significance, precise immunological mechanisms underlying pouchitis remain unclear. This study aimed to investigate the lymphocyte profile in the ileal pouch of patients with pouchitis compared to those with familial adenomatous polyposis (FAP) and ulcerative colitis without pouchitis using flow cytometry and immunohistochemical techniques. We prospectively analyzed endoscopic biopsy specimens from the ileal pouches of 15 patients and categorized them into three groups: FAP, ulcerative colitis with an inflammation-free pouch (UC-I), and ulcerative colitis with ulcers and/or erosions in the pouch (UC-UE). Flow cytometry was used to assess various T-lymphocyte markers, including cluster of differentiation (CD) 4, CD8, CD56, and human leukocyte antigen (HLA)-DR. Immunohistochemistry was performed to visualize the spatial distribution of CD3+, CD56+, and HLA-DR+ cells in the pouch mucosa. We observed significantly reduced CD56+/CD3+ and CD8+/CD3+ ratios in the UC-UE group compared to those in the FAP group, indicating a disruption in natural killer T-cell populations. Immunohistochemical analysis revealed that the spatial distribution of lymphocytes differed among the non-inflamed mucosa, dense lymphocyte infiltration, and lymphoid follicles, with these components frequently intermingling. CD56 + cells were less abundant in areas with dense lymphocyte infiltration, whereas HLA-DR+ cells were more abundant. Our study revealed a decrease in CD56+ natural killer T cells and an increase in HLA-DR+-activated T cells in areas with dense lymphocyte infiltration, suggesting an association between these cells and pouchitis in ulcerative colitis. The distinct patterns observed in non-inflamed mucosa, areas with dense lymphocyte infiltration, and lymphoid follicles underscore the need for further analyses of these three segments to elucidate the immunological mechanisms underlying pouchitis.

587. PD-L1 EXPRESSION AND CD8+ TUMOR-INFILTRATING LYMPHOCYTES CHANGES AFTER PREOPERATIVE CHEMORADIOTHERAPY IN ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Abstract Background Neoadjuvant chemoradiotherapy (nCRT) has been established as a standard treatment for locally advanced esophageal squamous cell carcinoma (SqCC), but there are still insufficient research advances on the incorporation of immunologic agents. The aim of this study was to explore immune microenvironment changes before and after nCRT. Methods A total of 101 patients who underwent nCRT followed by radical surgery for esophageal SqCC in a single institution between 2005 and 2021 were analyzed. Pre-nCRT endoscopic biopsy and post-nCRT surgical specimen were evaluated using tissue microarray. Immunohistochemical staining for CD3, CD8, and PD-L1 were performed. Tumor-infiltrating lymphocytes (TIL) density were independently evaluated by blinded pathologist (total number of 2+ to 3+ cells/total area (mm2)). Results Compared to pre-nCRT biopsy, PD-L1 expression (8.7% vs. 14.0%, p&amp;lt;0.001) and TIL density (259.1 vs. 566.9, p&amp;lt;0.001) were significantly increased in surgical specimen after nCRT. When divided into groups according to nCRT response, post-nCRT TIL density (p=0.341), fold changes of TIL density (p=0.749), and PD-L1 expression (p=0.642) were not significantly different between ypCR (n=23) and non-ypCR group (n=78). In ypT0 group (n=36), post-nCRT TIL density was marginally higher than that of non-ypT0 group (404 vs. 259, p = 0.050). Conclusion Irrespective of clinical responses, PD-L1 expression and TIL density were both increased after nCRT. Our results could help the development of combination strategy of immunologic drugs and seek the possibility of an organ-saving strategy that will contribute to improving quality of life of patients.

Human Epidermal Growth Factor 2 (Her-2) Expression in Gastric and Gastroesophageal Carcinomas: A Clinicopathological Evaluation in a Tertiary Care Institute.

Introduction Gastric carcinoma is a significant global health concern, known for its high mortality rate. HER-2 overexpression is observed in a notable proportion of gastric carcinoma and is associated with a worse prognosis. However, HER-2 expression enables targeting the protein by monoclonal antibodies that improve overall survival in HER-2-positive gastric cancers. This study aims to evaluate the HER-2 expression in gastric and gastroesophageal carcinomas. Materials and methods This observational study was conducted in the Department of Pathology, involving 60 endoscopic biopsy and resection specimens of gastric and gastroesophageal carcinomas. HER-2 expression was assessed by immunohistochemistry (IHC) based on the Trastuzumab for GAstric Cancer (ToGA) trial's scoring system. The primary outcome was HER-2 status, with statistical analysis performed to evaluate associations with various clinicopathological parameters. Results Among 60 cases, 26 (43.3%) showed HER-2 positivity. HER-2 positivity was significantly (p=0.004) associated with age, being higher in 20-39 years and ≥80 years age groups. Gender and tumor location were not significantly associated with HER-2 positivity. Moderate and poorly differentiated carcinomas exhibited higher HER-2 positivity. Histological types, tubular adenocarcinoma, and papillary adenocarcinoma showed significant (p=0.01) association with HER-2 positivity compared to other types. Conclusion HER-2 status assessment is crucial in managing gastric and gastroesophageal carcinomas. HER-2 positivity is notably higher in certain age groups and histological types particularly tubular and papillary adenocarcinoma, and in moderately to poorly differentiated carcinomas. These insights can aid in selecting appropriate gastric and gastroesophageal carcinomas that warrant HER-2 testing on IHC. Identifying gastric and gastroesophageal carcinomas that show HER2 expression may highlight potential candidates for targeted therapy.

A case of early-stage type 3 gastric neuroendocrine tumor in the upper body of the stomach: is endoscopic resection feasible?

Although gastric neuroendocrine tumors (NETs) are uncommon compared with gastric carcinomas, the incidence of NETs has been recently increasing. Gastric NETs are classified into three subgroups, and among these, gastrin-independent sporadic type 3 gastric NETs have a poor prognosis because of frequent lymph node or distant metastasis. We experienced a case of an early-stage type 3 gastric NET associated with lymphovascular and submucosal invasion. In a 54year-old woman, esophagogastroduodenoscopy performed during a health screening identified an elevated lesion of the upper body of the stomach. The results of immunohistochemical analyses of endoscopic biopsy specimens obtained from the lesion were positive for chromogranin A and synaptophysin, indicating an NET. Because the patient's serum gastrin level was normal and she had no predisposing conditions for NET development, the tumor was diagnosed as a type 3 gastric NET. The patient underwent local resection of the tumor and regional lymph node dissection. The resected specimen indicated a diagnosis of type 3 gastric NET with invasion into the submucosa and lymphatic duct. This is an extremely rare case of an early-stage type 3 gastric NET. Our discussion provides insight into the pathogenesis and development of these tumors and the appropriate therapeutic strategy.

Study of Prevalence of Gastritis Caused by H. pylori and Correlation of Urease Test with Serology (ELISA) Test.

H. pylori are a pathogen of global importance. Gram-negative curved flagellate bacilli are implicated as one of the most trivial complaints of and are associated with peptic ulcer disease gastritis ulcer and gastric malignancy. This study was performed to find out the prevalence of Helicobacter pylori (H. pylori) infection in patients presenting the symptoms related with gastritis with or without chemically known peptic ulcer. The study was undertaken with the help of the Christensen and quotes urease test on endoscopic biopsy specimen and correlated with the detection of immunoglobulin IgG in the serum against H. pylori by an ELISA technique. A total of 67 cases were analyzed in which 29 (43%) cases were positive for H. pylori. The endoscopic findings of acid peptic diseases show 21 (31.4%) cases of stomach ulcer, and 3 (4.5%) have esophagitis, whereas 43 (64.1%) have nonulcer dyspepsia. There is strong positive association between the urease tesr and ELISA test. The urease test is a quick and inexpensive test with high specificity and sensitivity, but since it is an invasive test, it has reduced patient compliance.

Histopathological staging and differential diagnosis of marginal zone lymphoma of gastric mucosa-associated lymphoid tissue

The purpose of this study was to explore the histopathological staging and differential diagnosis of marginal zone lymphoma in gastric mucosa-associated lymphoid tissue (MALT lymphoma). We performed detailed histomorphology and immunohistochemistry investigations as well as genetic testing on endoscopic biopsy and endoscopic mucosal resection specimens from 18 patients with gastric MALT lymphoma. We found that gastric MALT lymphoma typically begins as a small, isolated area outside the lymphoid follicular mantle zone or proliferates in a multifocal, patchy manner, gradually spreads to the interfollicular zone, forming diffuse proliferation, invades the gastric mucosal glands, and infiltrates or proliferates into the center of peripheral reactive lymphoid follicles. Abnormally proliferating lymphocytes invade the surrounding lymphoid follicles, resulting in damage, atrophy, and disappearance of their normal follicles as well as of the gastric mucosa glands, forming diffuse proliferation. Redifferentiation and proliferation lead to the transformation of lymphocytes; that is, MALT transitions into highly invasive lymphoma. Based on our findings in this study, we propose the following five stages in the process of development and progression of gastric MALT lymphoma: the stage of cell proliferation outside the lymphoid follicular mantle zone; the stage of heterogeneous proliferative lymphoepithelial lesion; the stage of reactive lymphoid follicular implantation; the stage of lymphoid follicular clonal proliferation; and the stage of MALT transforming into highly invasive lymphoma. We examined the differential diagnosis of histopathological features at each stage. The clinicopathological staging of gastric MALT lymphoma can help clinicians provide accurate treatment and track malignant cell transformation, thus playing a significant role in controlling its development and progression.

K-ras mutation detected by peptide nucleic acid-clamping polymerase chain reaction, Ki-67, S100P, and SMAD4 expression can improve the diagnostic accuracy of inconclusive pancreatic EUS-FNB specimens

ObjectivesWe aimed to assess the diagnostic utility of an immunohistochemical panel including calcium-binding protein P, p53, Ki-67, and SMAD family member 4 and K-ras mutation for diagnosing pancreatic solid lesion specimens obtained by endoscopic ultrasound-guided fine-needle biopsy and to confirm their usefulness in histologically inconclusive cases. MethodsImmunohistochemistry and peptide nucleic acid-clamping polymerase chain reaction for K-ras mutation were performed on 96 endoscopic ultrasound-guided fine-needle biopsy specimens. The diagnostic efficacy of each marker and the combination of markers was calculated. The diagnostic performances of these markers were evaluated in 27 endoscopic ultrasound-guided fine-needle biopsy specimens with histologically inconclusive diagnoses. A classification tree was constructed. ResultsK-ras mutation showed the highest accuracy and consistency. Positivity in more than two or three of the five markers showed high diagnostic accuracy (94.6 % and 93.6 %, respectively), and positivity for more than three markers showed the highest accuracy for inconclusive cases (92.0 %). A classification tree using K-ras mutation, Ki-67, S100P, and SMAD4 showed high diagnostic performance, with only two misclassifications in inconclusive cases. ConclusionsK-ras mutation detection via peptide nucleic acid-clamping polymerase chain reaction is a stable and accurate method for distinguishing between pancreatic ductal adenocarcinoma and non-pancreatic ductal adenocarcinoma lesions. A classification tree using K-ras mutation, Ki-67, S100P, and SMAD4 helps increase the diagnostic accuracy of cases that are histologically difficult to diagnose.

Differential diagnosis of gastric low- and high grade dysplasia using C6orf15 protein

ObjectiveTo investigate the expression of C6orf15 protein in gastric endoscopic biopsy specimens and its usage as an ancillary diagnostic biomarker in determining the grade of gastric dysplasia. MethodsWe selected 102 patients with gastric endoscopic biopsy specimens from Jinling Hospital. These were divided into four groups: 22 cases of gastric mucosal benign lesions, 28 with low-grade dysplasia (LGD, intestinal-type: 21 cases，foveolar-type: 7cases), 28 with high-grade dysplasia (HGD, intestinal-type: 20 cases，foveolar-type: 8 cases), and 24 cases of gastric adenocarcinoma. We examined the expressions of C6orf15, P53, and Ki67 in 102 gastric endoscopic biopsy specimens, including 47 cases with accompanying endoscopic submucosal dissection (ESD) specimens, using immunohistochemistry. ResultsIn gastric HGD and gastric adenocarcinoma, the c6orf15 protein exhibits diffuse and strong cytoplasmic expression in tumor cells. Conversely, in gastric LGD and benign gastric mucosal lesions, the c6orf15 protein shows negative or faint yellow cytoplasmic staining. The expression rate of C6orf15 in high-grade gastric dysplasia (HGD, 93 %) and gastric adenocarcinoma (100 %) was significantly higher than in the gastric mucosal benign lesion group (0 %) and the low-grade dysplasia (LGD, 7 %) group (P < 0.001). ConclusionThe detection of C6orf15 protein expression could serve as a valuable adjunctive diagnostic tool for distinguishing between gastric HGD, LGD, and benign lesions. The combined assessment of C6orf15, P53, and Ki67 expressions may be beneficial in determining the grade of gastric dysplasia and evaluating the risk of progression in gastric mucosal lesions in clinical practice.

Abstract 7623: Biomarker study to personalized neoadjuvant chemotherapy using preoperative gastric cancer specimens of biopsy from the COMPASS trial, a phase II randmazed controlled trial

Abstract Background and Aim: The results of COMPASS, a randomized phase II trial, suggest that preoperative adjuvant chemotherapy (NAC) regimen or course for locally advanced gastric cancer (GC) does not affect overall survival (OS). However, we hypothesized that some NAC regimens may be more effective for OS on a case-by-case basis. Furthermore, we searched for biomarkers, assuming that further improvement in the outcome of locally advanced GC could be expected if appropriate NAC regimens could be selected using biomarkers before treatment initiation. Materials and Methods: RNA was extracted from endoscopic biopsy specimens of primary tumors collected prior to NAC administration in COMPASS patients, and real-time polymerase chain reaction (PCR) of 127 genes was performed to identify genes with significant (P &amp;lt; 0.05) interaction P values for survival with each regimen and stratified OS with each regimen. Genes were identified and biomarkers were searched at the protein level using immunohistochemical analysis. Results: The THBS1, MSI1, and IGF2BP3 genes were identified as genes whose expression levels significantly (P &amp;lt; 0.05) stratified survival for each regimen and had significant (P &amp;lt; 0.05) interaction P values. Furthermore, a strong correlation was observed between each gene and THBS1, MSI1, and IGF2BP protein expression by immunohistochemical analysis, confirming that protein expression levels by immunohistochemical analysis are also useful as biomarkers. Conclusion: Using endoscopic biopsy specimens prior to NAC for locally advanced GC, biomarkers were identified to select NAC regimens over predicted OS. The results of this study may guide the conduct of clinical trials of individualized treatment of NAC using biomarkers. Citation Format: Takashi Oshima. Biomarker study to personalized neoadjuvant chemotherapy using preoperative gastric cancer specimens of biopsy from the COMPASS trial, a phase II randmazed controlled trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7623.

A Preliminary Study Assessing a Transfer Learning Approach to Intestinal Image Analysis to Help Determine Treatment Response in Canine Protein-Losing Enteropathy.

Dogs with protein-losing enteropathy (PLE) caused by inflammatory enteritis, intestinal lymphangiectasia, or both, have a guarded prognosis, with death occurring as a result of the disease in approximately 50% of cases. Although dietary therapy alone is significantly associated with a positive outcome, there is limited ability to differentiate between food-responsive (FR) PLE and immunosuppressant-responsive (IR) PLE at diagnosis in dogs. Our objective was to determine if a transfer learning computational approach to image classification on duodenal biopsy specimens collected at diagnosis was able to differentiate FR-PLE from IR-PLE. This was a retrospective study using paraffin-embedded formalin-fixed duodenal biopsy specimens collected during upper gastrointestinal tract endoscopy as part of the diagnostic investigations from 17 client-owned dogs with PLE due to inflammatory enteritis at a referral teaching hospital that were subsequently classified based on treatment response into FR-PLE (n = 7) or IR-PLE (n = 10) after 4 months of follow-up. A machine-based algorithm was used on lower magnification and higher resolution images of endoscopic duodenal biopsy specimens. Using the pre-trained Convolutional Neural Network model with a 70/30 training/test ratio for images, the model was able to differentiate endoscopic duodenal biopsy images from dogs with FR-PLE and IR-PLE with an accuracy of 83.78%. Our study represents an important first step toward the use of machine learning in improving the decision-making process for clinicians with regard to the initial treatment of canine PLE.

P342 Role of the Number and Location of Endoscopic Biopsies on the Detection of Granuloma in Patients with Isolated Intestinal Tuberculosis

Abstract Background Detecting granulomas is valuable for the diagnosis of isolated intestinal tuberculosis (ITB). However, how to perform an effective endoscopic biopsy remains unclear. We aimed to explore the impact of the number and location of endoscopic biopsies on granuloma detection in patients with isolated ITB. Methods A prospective analysis was conducted in 50 patients with confirmed isolated ITB who underwent predetermined endoscopic biopsy and pathological tests. 50 patients with isolated ITB were included for analysis. The diagnosis was confirmed based on microbiological, endoscopic, and histopathological evidences. For each patient, eight endoscopic biopsy specimens were obtained from either ulcer bases (n=4) or ulcer margins (n=4). After fixation, the specimens were serially sectioned into 8 slices on average. The slices were then stained and examined by an experienced gastrointestinal pathologist who were blinded to the patient information. Results The detection rates of granulomas from 2, 4, 6, and 8 biopsy specimens were 10, 28, 50, and 82%, respectively (5/50 vs 14/50 vs 25/50 vs 41/50, P&amp;lt;0.00001). When 4 biopsy specimens were used, the granuloma detection rate with specimens from the ulcer base was significantly higher than that from the ulcer margin (41/50 vs 14/50, P&amp;lt;0.0001). 34% (17/50) of the patients had necrotising-confluent granuloma, and 12% (6/50) had confluent (&amp;gt;400 um) granuloma. In total, 205 granulomas were identified in 41 patients. Multi-granulomas were detected on 49 slices while mono-granulomas on were detected on 72 slices. 62.9% (129/205) of granulomas were detected in the ulcer base, 27.8% (57/205) in the lamina propria, and 9.3% (19/205) in the submucosa. Conclusion Using more than 8 or 4 biopsy specimens from the ulcer base improved the detection rate (over 50%) of necrotising or confluent granulomas for ITB. To improve the accuracy of diagnosis, clinicians should obtain ≥4 pieces of endoscopic biopsy from the ulcer base and conduct a deep biopsy into the lamina propria. Nevertheless, the integration of clinical characteristics and anti-TB responses is still required for suspected patients with undetected granulomas.

Small intestinal perforation manifesting as post-transplant lymphoproliferative disorder occurring 23 years after living lung transplantation: a case report

A Japanese female patient underwent a living lung transplant at age 29 and has been on immunomodulatory drug therapy since then. At age 52, she presented with sudden hematochezia. Despite abdominal computed tomography scan, esophagogastroduodenoscopy, and colonoscopy, no definitive source of bleeding was identified. Considering the possibility of small bowel bleeding, video capsule endoscopy was performed, which revealed a suspected ulcerative lesion in the jejunum. Subsequent per-oral double-balloon endoscopy confirmed the presence of an ulcerative lesion in the jejunum. A potential pathological diagnosis of post-transplant lymphoproliferative disorder (PTLD) was considered based on endoscopic biopsy specimens from the jejunal lesion. However, before the pathologic biopsy results were available, the patient experienced small intestinal perforation, necessitating emergency partial resection. Pathologic examination revealed a dense proliferation of medium-to-large atypical lymphocytes with neutrophilic infiltration in the perforated area of the small intestinal wall. Immunostaining showed lymphoid cells positive for CD20 but negative for CD3. Epstein-Barr virus (EBV) -encoded RNA was detected by in situ hybridization, and Ki-67 staining demonstrated a higher percentage of positive cells. Consequently, an EBV-positive diffuse large B-cell lymphoma, developed as PTLD, was diagnosed. Complete remission was achieved with a reduced immunomodulatory drug dosage and rituximab therapy. She has been alive for 8 months postoperatively without recurrence. This case suggests that PTLD should be considered in assessing patients presenting with abdominal symptoms following organ transplantation.

Histopathological Study of Upper Gastrointestinal Tract Endoscopic Biopsies in a Teaching Hospital

Background: When a patient has an upper gastrointestinal disorder-which frequently manifests as dyspepsia-upper gastrointestinal endoscopy is considered the preferred diagnostic procedure. Without a biopsy, endoscopy cannot be considered complete, and the most reliable method for diagnosing lesions seen during endoscopy is histopathology. Methodology: This retrospective study was conducted in the Department of Pathology at A.C.S Medical College and Hospital for one year duration from July 2022 to July 2023. A total of fifty-five endoscopic biopsy specimens were obtained; they were preserved in 10% formalin and regularly stained with hematoxylin and eosin. Results: The majority was found to be 45.4% (25/40) of those aged 61-70, 36.3% (20/55) of those aged 51-60, and 18.1% (10/55) of those aged 40-50.Thirty patients (18.7%) had duodenal lesions, 80 cases (50%) had stomach lesions, and 50 cases (31.2%) had oesophageal lesions. Most upper gastrointestinal tract endoscopic biopsies came from the stomach. Conclusion: Endoscopy is insufficient without biopsy, and the gold standard for diagnosing lesions seen during an endoscopy is histopathology. The particular location of mucosal lesions can be seen with the use of upper gastrointestinal tract endoscopy. Therefore, we may draw the conclusion that using these two approaches together offers a potent diagnostic tool for improved patient care.

REV7 is involved in outcomes of platinum-based chemotherapy in pancreatic cancer by controlling the DNA damage response.

REV7 is a multifunctional protein implicated in various biological processes, including DNA damage response. REV7 expression in human cancer cells affects their sensitivity to DNA-damaging agents. In the present study, we investigated the significance of REV7 in pancreatic ductal adenocarcinoma (PDAC). REV7 expression was immunohistochemically examined in 92 resected PDAC specimens and 60 endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) specimens of unresectable PDAC treated with platinum-based chemotherapy, and its association with clinicopathologic features was analyzed. Although REV7 expression was not significantly associated with the progression of primary tumors (T-factor and Stage) in either resected or unresectable PDAC, decreased levels of REV7 expression in EUS-FNAB specimens of unresectable PDAC were significantly associated with better outcomes of platinum-based chemotherapy and a favorable prognosis. REV7-deficient PDAC cell lines showed suppressed cell growth and enhanced sensitivity to cisplatin invitro. Tumor-bearing mice generated using REV7-deficient PDAC cell lines also showed enhanced sensitivity to cisplatin invivo. RNA sequencing analysis using WT and REV7-deficient PDAC cell lines revealed that REV7 inactivation promoted the downregulation of genes involved in the DNA repair and the upregulation of genes involved in apoptosis. Our results indicate that decreased expression of REV7 is associated with better outcomes of platinum-based chemotherapy in PDAC by suppressing the DNA damage response. It is also suggested that REV7 is a useful biomarker for predicting the outcome of platinum-based chemotherapy and the prognosis of unresectable PDAC and is a potential target for PDAC treatment.