Gastrointestinal Adenocarcinoma Research Articles

Clinical Rarity Unveiled: Adenocarcinoma with Enteroblastic Differentiation at the Gastroesophageal Junction in a Young Patient - A Diagnostic Challenge Shaping Therapeutic Paradigms

Abstract Introduction/Objective This report details a case of a young patient diagnosed with an adenocarcinoma with enteroblastic differentiation at the gastroesophageal junction (GEJ), characterized by Alpha-Fetoprotein (AFP) production. This manifestation previously rarely documented in young patients (25-44 years old), underscores the critical role of precise pathology diagnosis in guiding effective patient management. Methods/Case Report The patient’s clinical presentation included chest pain, abdominal pain, and weight loss, prompting imaging studies revealing liver masses, lesions in the lung and adrenal gland, and retroperitoneal adenopathy with unremarkable testicular findings. Rapidly progressing dysphagia led to a liver biopsy and esophagogastroduodenoscopy (EGD), where a fungating mass extending from the distal esophagus into the stomach was biopsied. A subsequent serologic test unveiled an elevated serum AFP level (approximally 31, 000 ng/ml). Results (if a Case Study enter NA) Histological examination revealed similarities between the liver and distal esophageal tumors, characterized by moderately differentiated carcinoma with solid and glandular growth patterns. The tumor cells, resembling fetal gut epithelium, exhibited positive immunostaining for SALL4, AFP, CK8-18, CK19, and CDX2. A diagnosis of adenocarcinoma with enteroblastic differentiation at the GEJ was determined, correlating with clinical and radiological assessments. Despite initiating one cycle of gastrointestinal related chemotherapy, the patient succumbed to tumor lysis syndrome within a month of diagnosis. Conclusion This case highlights the critical need for a comprehensive differential diagnosis when encountering young patients with AFP-producing malignancies. Although metastatic non-seminomatous germ cell cancer is a primary consideration, upper gastrointestinal adenocarcinoma with unique characteristics, as demonstrated in this case, requires distinct therapeutic approaches, emphasizing the importance of accurate and timely diagnosis.

TTF-1 is a highly sensitive but not fully specific marker for pulmonary and thyroidal cancer: a tissue microarray study evaluating more than 17,000 tumors from 152 different tumor entities.

Thyroid transcription factor 1 (TTF-1) immunohistochemistry (IHC) is routinely used for the distinction of primary pulmonary adenocarcinomas. However, TTF-1 can also occur in other malignancies. A tissue microarray containing 17,772 samples from 152 different tumor types was analyzed. Napsin-A, CK20, SATB2, FABP1, and Villin-1 IHC data were available from previous studies. TTF-1 staining was seen in 82 of 152 tumor categories including thyroidal cancers (19-100%), adenocarcinomas (94%), neuroendocrine tumors (67%) of the lung, small cell neuroendocrine carcinomas (71-80%), mesenchymal tumors (up to 42%), and thymomas (39%). Comparative analysis of TTF-1 and Napsin-A revealed a sensitivity/specificity of 94%/86% (TTF-1), 87%/98% (Napsin-A), and 85%/99.1% (TTF-1 and Napsin-A) for the distinction of pulmonary adenocarcinomas. Combined analysis of TTF-1 and enteric markers revealed a positivity for TTF-1 and at least one enteric marker in 22% of pulmonary adenocarcinomas but also a TTF-1 positivity in 6% of colorectal, 2% of pancreatic, and 3% of gastric adenocarcinomas. TTF-1 is a marker of high sensitivity but insufficient specificity for pulmonary adenocarcinomas. A small fraction of TTF-1-positive gastrointestinal adenocarcinomas represents a pitfall mimicking enteric-type pulmonary adenocarcinoma. Combined analysis of TTF-1 and Napsin-A improves the specificity of pulmonary adenocarcinoma diagnosis.

5-Fluorouracil-Induced Leukoencephalopathy: Report of Two Cases and Review of Literature

Abstract5-fluorouracil (5FU) forms an important component of chemotherapy regimens used in various gastrointestinal (GI) adenocarcinomas and head and neck squamous cell carcinomas. Leukoencephalopathy is a rare adverse effect of 5FU, mediated by hyperammonemia and hyperlactatemia. We report cases of two patients with GI adenocarcinomas who developed neurological symptoms while on 5FU infusion. The neuroimaging and biochemical parameters were suggestive of toxic leukoencephalopathy. They were managed with cessation of the drug and short-term antiepileptic therapy. We also discuss the pathophysiology of this adverse effect and its management.

GASTROINTESTINAL TRACT ADENOCARCINOMA IDENTIFIED IN CAPTIVE GILA MONSTERS (HELODERMA SUSPECTUM) IN A NORTH AMERICAN ZOO, 1997-2023.

Neoplasia in the Gila monster (Heloderma suspectum) is not commonly investigated, and literature regarding the prevalence and type of neoplasms that affect this species is sparse. Gastrointestinal tract adenocarcinoma (GTA) in particular has only been reported twice in Gila monsters, once in the small intestine and once in the colon. In this case series, 50% (7/14) of the Gila monsters presented to the pathology service at Smithsonian's National Zoo and Conservation Biology Institute (SNZCBI) over the span of 26 yr (1997-2023) were found to have intestinal and/or colonic adenocarcinoma. The frequency of GTA reported in this collection likely represents a multifactorial etiology including geriatric age of specimens, chronic inflammation, gastrointestinal tract infection, and/or increased cognizance of the disease because of previous reports within the collection. An increased awareness of GTA in this species may lead to improved recognition of the disease.

Prevalence of S-methyl-5'-thioadenosine Phosphorylase (MTAP) Deficiency in Human Cancer: A Tissue Microarray Study on 13,067 Tumors From 149 Different Tumor Types.

Loss of S-methyl-5'-thioadenosine phosphorylase (MTAP) expression is a common event in cancer leading to a critical vulnerability of cancer cells towards anti-cancer drugs. Homozygous MTAP deletions result in a complete expression loss that can be detected by immunohistochemistry (IHC). In this study, a tissue microarray containing 17,078 samples from 149 different tumor entities was analyzed by IHC, and complete MTAP loss was validated by fluorescence in situ hybridization. MTAP loss was observed in 83 of 149 tumor categories, including neuroendocrine neoplasms (up to 80%), Hodgkin lymphoma (50.0%), mesothelioma (32.0% to 36.8%), gastro-intestinal adenocarcinoma (4.0% to 40.5%), urothelial neoplasms (10.5% to 36.7%), squamous cell carcinomas (up to 38%), and various types of sarcomas (up to 20%) and non-Hodgkin lymphomas (up to 14%). Homozygous MTAP deletion was found in 90% to 100% of cases with MTAP expression loss in most tumor categories. However, neuroendocrine tumors, Hodgkin lymphomas, and other lymphomas lacked MTAP deletions. MTAP deficiency was significantly linked to unfavorable tumor phenotype in selected tumor entities and the presence of PD-L1 expression on tumor cells, absence of PD-L1 expression on immune cells, and a low density of CD8 + lymphocytes. In summary, MTAP deficiency can occur in various tumor entities and is linked to unfavorable tumor phenotype and noninflamed tumor microenvironment, but is not always related to deletions. MTAP IHC is of considerable diagnostic value for the detection of neoplastic transformation in multiple different applications.

Cadaveric Study: Sign of Leser-Trélat Associated with Breast Cancer

INTRODUCTION: Seborrheic keratoses (SK) is considered the most common benign skin lesions found in individuals that are middle aged and older. In dermatology practice, these lesions pose no threat to the individual but can be concerning for cosmetic and underlying malignancy reasons when they cover most of the skin surface. Of specific concern is the sign of Leser-Trélat, which has been documented as a cutaneous harbinger of underlying malignancy associated with proliferation of the size and/or number seborrheic keratoses. The rare sign is usually caused by malignancies such as gastrointestinal adenocarcinoma, but also lung, kidney, liver, or pancreatic cancer. This case report will describe the histology of the skin lesions in Lesar Trélat and analyze the current literature regarding its association with breast cancer, which is quite rare. RESOURCES: For this case study, a cadaver from the body donor program in Philadelphia College of Osteopathic Medicine (PCOM), South Georgia was used. Skin samples were sent to Colquitt Regional Center for processing, where sections were embedded in paraffin and were stained with H&E stain. A pathologist reported histopathological findings of the skin lesions and the breast tissue samples. DESCRIPTION: Multiple SK lesions covering the face, abdomen, back, as well as both upper and lower extremities were observed in one of the cadavers in the gross anatomy laboratory. Due to the significant number of pigmented, verrucous lesions, the sign of Leser-Trélat was clinically postulated, later confirmed during routine laboratory dissection of the breast tissue. Histology sections confirmed not only multiple SK lesions in the skin, but also revealed an associated breast cancer in the form of an infiltrative ductal carcinoma. SIGNIFICANCE: The sign of Leser-Trélat is rare by itself and its association with breast cancer is even more uncommon. Once a clinician recognizes the multiple SK eruptions, the patient should be meticulously investigated for not only for an underlying GI malignancy, but also for other cancers like breast cancer. Additionally, a case report confirmed malignant melanoma that mimicked sign of Leser-Trélat, warranting the importance of further analyzing the pathology diagnosis when there is a proliferation of multiple seborrheic keratoses.Therefore, biopsy and histology diagnosis is crucial for ruling out both cutaneous as well as underlying malignancies and should be encouraged when patients present in clinic rather than assuming the typical benign characteristics of seborrheic keratosis.

Unveiling the secrets of gastrointestinal mucous adenocarcinoma survival after surgery with artificial intelligence: A population-based study.

Research on gastrointestinal mucosal adenocarcinoma (GMA) is limited and controversial, and there is no reference tool for predicting postoperative survival. To investigate the prognosis of GMA and develop predictive model. From the Surveillance, Epidemiology, and End Results database, we collected clinical information on patients with GMA. After random sampling, the patients were divided into the discovery (70% of the total, for model training), validation (20%, for model evaluation), and completely blind test cohorts (10%, for further model evaluation). The main assessment metric was the area under the receiver operating characteristic curve (AUC). All collected clinical features were used for Cox proportional hazard regression analysis to determine factors influencing GMA's prognosis. This model had an AUC of 0.7433 [95% confidence intervals (95%CI): 0.7424-0.7442] in the discovery cohort, 0.7244 (GMA: 0.7234-0.7254) in the validation cohort, and 0.7388 (95%CI: 0.7378-0.7398) in the test cohort. We packaged it into Windows software for doctors' use and uploaded it. Mucinous gastric adenocarcinoma had the worst prognosis, and these were protective factors of GMA: Regional nodes examined [hazard ratio (HR): 0.98, 95%CI: 0.97-0.98, P < 0.001)] and chemotherapy (HR: 0.62, 95%CI: 0.58-0.66, P < 0.001). The deep learning-based tool developed can accurately predict the overall survival of patients with GMA postoperatively. Combining surgery, chemotherapy, and adequate lymph node dissection during surgery can improve patient outcomes.

Epithelial Cell Adhesion Molecule (EpCAM) Expression in Human Tumors: A Comparison with Pan-Cytokeratin and TROP2 in 14,832 Tumors.

EpCAM is expressed in many epithelial tumors and is used for the distinction of malignant mesotheliomas from adenocarcinomas and as a surrogate pan-epithelial marker. A tissue microarray containing 14,832 samples from 120 different tumor categories was analyzed by immunohistochemistry. EpCAM staining was compared with TROP2 and CKpan. EpCAM staining was detectable in 99 tumor categories. Among 78 epithelial tumor types, the EpCAM positivity rate was ≥90% in 60 categories-including adenocarcinomas, neuroendocrine neoplasms, and germ cell tumors. EpCAM staining was the lowest in hepatocellular carcinomas, adrenocortical tumors, renal cell neoplasms, and in poorly differentiated carcinomas. A comparison of EpCAM and CKpan staining identified a high concordance but EpCAM was higher in testicular seminomas and neuroendocrine neoplasms and CKpan in hepatocellular carcinomas, mesotheliomas, and poorly differentiated non-neuroendocrine tumors. A comparison of EpCAM and TROP2 revealed a higher rate of TROP2 positivity in squamous cell carcinomas and lower rates in many gastrointestinal adenocarcinomas, testicular germ cell tumors, neuroendocrine neoplasms, and renal cell tumors. These data confirm EpCAM as a surrogate epithelial marker for adenocarcinomas and its diagnostic utility for the distinction of malignant mesotheliomas. In comparison to CKpan and TROP2 antibodies, EpCAM staining is particularly common in seminomas and in neuroendocrine neoplasms.

Illuminating new possibilities: Effects of copper oxide nanoparticles on gastrointestinal adenocarcinoma cells in hypoxic condition

Cancer remains a major global health concern, necessitating the development of novel therapeutic approaches. Hypoxia is a common characteristic of solid tumors that plays a critical role in tumor progression, making it a prime target for anticancer therapies. This study aimed to determine the effects of copper oxide nanoparticles (CuONPs) on human gastrointestinal cancer cells in hypoxic condition for the first time. Toxicity of CuONPs was evaluated on human colon and gastric adenocarcinoma cells and normal fibroblasts by alamarBlue assay. Real-time polymerase chain reaction (PCR) was performed to study the effects of CuONPs on genes involved in cell apoptosis. To elucidate the molecular mechanisms underlying the effects of CuONPs in hypoxic condition, molecular docking was conducted on HIF-1α. Results revealed dose- and cell-type-dependent toxic effects of CuONPs, as a more significant (p < 0.0001) decrease in viability of LoVo cells (23 %) was observed compared to MKN-45 and HDF cells. In addition, CuONPs significantly (p < 0.0001) reduced LoVo cell viability down to 30.2 % in hypoxic condition. Gene expression analysis revealed significant (p < 0.0001) overexpression of P53 and BAX but downregulation of BCL-2 and CCND1 after treatment with CuONPs. Molecular docking indicated the preferable binding of CuONPs to the HIF-1α PAS-B domain through interaction with 15 residues with −4.8 kcal/mol binding energy. Our findings open up new possibilities for modulating HIF-1 activity and inhibiting hypoxia-induced tumor progression.

Cadherin-17 as a target for the immunoPET of adenocarcinoma

PurposeCadherin-17 (CDH17) is a calcium-dependent cell adhesion protein that is overexpressed in several adenocarcinomas, including gastric, colorectal, and pancreatic adenocarcinoma. High levels of CDH17 have been linked to metastatic disease and poor prognoses in patients with these malignancies, fueling interest in the protein as a target for diagnostics and therapeutics. Herein, we report the synthesis, in vitro validation, and in vivo evaluation of a CDH17-targeted 89Zr-labeled immunoPET probe.MethodsThe CDH17-targeting mAb D2101 was modified with an isothiocyanate-bearing derivative of desferrioxamine (DFO) to produce a chelator-bearing immunoconjugate — DFO-D2101 — and flow cytometry and surface plasmon resonance (SPR) were used to interrogate its antigen-binding properties. The immunoconjugate was then radiolabeled with zirconium-89 (t1/2 ~ 3.3 days), and the serum stability and immunoreactive fraction of [89Zr]Zr-DFO-D2101 were determined. Finally, [89Zr]Zr-DFO-D2101’s performance was evaluated in a trio of murine models of pancreatic ductal adenocarcinoma (PDAC): subcutaneous, orthotopic, and patient-derived xenografts (PDX). PET images were acquired over the course of 5 days, and terminal biodistribution data were collected after the final imaging time point.ResultsDFO-D2101 was produced with a degree of labeling of ~ 1.1 DFO/mAb. Flow cytometry with CDH17-expressing AsPC-1 cells demonstrated that the immunoconjugate binds to its target in a manner similar to its parent mAb, while SPR with recombinant CDH17 revealed that D2101 and DFO-D2101 exhibit nearly identical KD values: 8.2 × 10−9 and 6.7 × 10−9 M, respectively. [89Zr]Zr-DFO-D2101 was produced with a specific activity of 185 MBq/mg (5.0 mCi/mg), remained >80% stable in human serum over the course of 5 days, and boasted an immunoreactive fraction of >0.85. In all three murine models of PDAC, the radioimmunoconjugate yielded high contrast images, with high activity concentrations in tumor tissue and low uptake in non-target organs. Tumoral activity concentrations reached as high as >60 %ID/g in two of the cohorts bearing PDXs.ConclusionTaken together, these data underscore that [89Zr]Zr-DFO-D2101 is a highly promising probe for the non-invasive visualization of CDH17 expression in PDAC. We contend that this radioimmunoconjugate could have a significant impact on the clinical management of patients with both PDAC and gastrointestinal adenocarcinoma, most likely as a theranostic imaging tool in support of CDH17-targeted therapies.

CA19-9 producing locally advanced papillary thyroid carcinoma: a case report.

CA19-9 is a tumor marker for gastrointestinal and biliary-pancreatic adenocarcinomas; however, its association with thyroid cancer is unknown. Here, we report a case of CA19-9 producing locally advanced papillary thyroid carcinoma (PTC). A 66-year-old woman who was identified with a thyroid tumor after a close examination of an elevated serum CA19-9 level, which was detected at health screening, was referred to our hospital. Ultrasonography revealed a 34 × 31mm hypoechoic lesion in the lower pole of the left thyroid lobe. Computed tomography revealed a solid thyroid tumor with tracheal invasion without any distant metastases. Bronchoscopy revealed tumor exposure into the tracheal lumen on the left side of the trachea. Fine-needle aspiration cytology led to a diagnosis of papillary thyroid carcinoma (PTC). The patient underwent a total thyroidectomy, tracheal sleeve resection with end-to-end anastomosis, and lymph node dissection in the left cervical and superior mediastinal regions (D3c) with a reversed T-shaped upper sternotomy down to the third intercostal level. Histopathological analysis confirmed the diagnosis of PTC with tracheal invasion and no lymph node metastases (pT4a Ex2 N0). Immunohistochemical staining showed the expression of CA19-9 in cancer cells. Postoperatively, the serum CA19-9 level of the patient decreased to within the normal range. Some PTCs produce CA19-9, although less frequently. When elevated serum CA19-9 levels are observed, PTC should be included in the differential diagnosis for further investigation.

Rainbow trout (Oncorhynchus mykiss, Walbaum 1792) adenocarcinoma investigation with various diagnostic imaging techniques.

Diagnostic imaging techniques provide a new aspect of the ante-mortem and post-mortem diagnostics in fish medicine. Ultrasonography, computed tomography (CT) and magnetic resonance imaging (MRI) can provide more information about the internal organs and pathognomic lesions. The authors used diagnostic imaging techniques to evaluate and describe the neoplastic malformation in a 3-year-old female rainbow trout (Oncorhynchus mykiss). The fish was examined with Siemens Somatom Definition AS + CT scanner and Siemens Biograph mMR scanner. The animal was lethargic and showed anorectic signs and muscular dystrophy. During the post-mortem investigation, histopathology and immunohistochemistry were also performed allowing us to identify the neoplasms. The results showed a large soft tissue mass in the first mid-intestine segment, which proved to be an adenocarcinoma. This subsequently led to digestion problems and absorption disorders. Immunohistochemically, neoplastic cells of carcinoma revealed E-cadherin and pancytokeratin positivity. This is the first study to report the use of MRI and CT for studying gastrointestinal adenocarcinoma in rainbow trout.

BCAT1, IKZF1 and SEPT9: methylated DNA biomarkers for detection of pan-gastrointestinal adenocarcinomas

Introduction Methylated circulating tumour DNA (ctDNA) blood tests for BCAT1/IKZF1 (COLVERA) and SEPT9 (Epi proColon) are used to detect colorectal cancer (CRC). However, there are no ctDNA assays approved for other gastrointestinal adenocarcinomas. We aimed to characterize BCAT1, IKZF1 and SEPT9 methylation in different gastrointestinal adenocarcinoma and non-gastrointestinal tumours to determine if these validated CRC biomarkers might be useful for pan-gastrointestinal adenocarcinoma detection. Methods Tissue DNA methylation data from colorectal (COAD, READ), gastroesophageal (ESCA, STAD), pancreatic (PAAD) and cholangiocarcinoma (CHOL) adenocarcinoma cohorts within The Cancer Genome Atlas were used for differential methylation analyses. Clinicodemographic predictors of BCAT1, IKZF1 and SEPT9 methylation, and the selectivity of hypermethylated BCAT1, IKZF1 and SEPT9 for colorectal adenocarcinomas in comparison to other cancers were each explored with beta regression. Results Hypermethylated BCAT1, IKZF1 and SEPT9 were each differentially methylated in colorectal and gastroesophageal adenocarcinomas. IKZF1 was differentially methylated in pancreatic adenocarcinoma. Hypermethylated DNA biomarkers BCAT1, IKZF1 and SEPT9 were largely stable across different stages of disease and were highly selective for gastrointestinal adenocarcinomas relative to other cancer types. Discussion Existing CRC methylated ctDNA blood tests for BCAT1/IKZF1 and SEPT9 might be usefully repurposed for use in other gastrointestinal adenocarcinomas and warrant further prospective ctDNA studies.

Where Do Surgical Resection and Radiosurgery Fall Short for Large Metastatic Brain Lesions?

INTRODUCTION: Stereotactic radiosurgery is established as the optimal treatment modality for metastatic disease of the brain, but there is ongoing debate about the optimal treatment for larger brain metastases. There have been few studies identifying and quantifying lesion characteristics where efficacy and local control of these lesions suffer. METHODS: We retrospectively identified patients who received surgical resection and/or hypofractionated Gamma Knife radiosurgery (HF-GKRS) between 2017 and 2022 for the treatment of metastatic brain tumors greater than 10cc. Clinical, treatment, and radiological data was collected. Local failure (LF) events were examined, and independent factors associated with subsequent local failure were identified. RESULTS: 105 lesions greater than 10cc (in 97 patients) were treated and the median patient follow-up was 10.1 months. The median gross tumor volume was 15.8cc (range 10.1-62.4). Prior surgical resection was performed on 49 lesions (54%). Tumor volume larger than 33.5cc (p = 0.029, 12-month LF rate 38%) and radioresistant histology (p=0.047, 12-month LF rate 54%) were associated with increased risk of LF (p=0.018) whereas surgical resection did not correlate with increased LC (p = 0.642, 12-month LF rate 19%). CONCLUSIONS: Patients with brain metastases that are greater than 4cm in diameter or are of radioresistant histology (primary origin of gastrointestinal adenocarcinoma, melanoma, or renal cell carcinoma) are especially prone to local failure despite aggressive surgical resection, stereotactic radiosurgery, and systemic chemotherapy. In these cases, the optimal management needs to be further elucidated and may involve preoperative stereotactic radiosurgery or intraoperative brachytherapy.

Cachexia-Affected Survival Based on Inflammatory Parameters Compared to Complex Conventional Nutritional Assessments in Patients with Pancreatic Cancer and Other Gastrointestinal Tumors-The CONKO 020 Investigation.

Pancreatic adenocarcinoma (PDAC) is still a complex, devastating disease. Cachexia symptoms frequently impair patient survival. This accompanying syndrome is commonly diagnosed late, when clinical signs become evident. Early diagnosis using conventional measurement methods is often difficult, and the discrimination of this disease from cancer progression is challenging and often overlaps. The aim of this study was to analyze whether conventional nutritional assessments or laboratory biomarkers are better predictive tools for the early detection of patients at risk of reduced survival. We analyzed a prospective predefined cohort of 182 patients with gastrointestinal cancer, 120 patients with PDAC and-as controls-62 patients with other gastrointestinal adenocarcinoma (oAC), from whom we have sufficient data of protocol-defined conventional nutritional assessments, clinical data, and specific laboratory parameters. at the time of tumor diagnosis, high inflammatory biomarkers (c-reactive protein (CRP), interleukin-6 (IL-6)) and albumin serum levels were associated with impaired OS in PDAC patients, but not in patients with oAC. Hemoglobin, body mass index (BMI), and bioelectrical assessments alone did not have a prognostic impact at the time of diagnosis. In a multivariate analysis, only CRP (HR 1.91 (1.25-2.92), p = 0.003) was found to be an independent prognostic factor in PDAC patients. Over the course of the disease in PDAC patients, inflammatory biomarkers, albumin, hemoglobin, and bioelectrical assessments were associated with impaired OS. In multivariate testing, CRP (HR 2.21 (1.38-3.55), p < 0.001) and albumin (HR 1.71 (1.05-2.77), p = 0.030) were found to be independent prognostic factors in PDAC patients. Specifically for PDAC patients, high inflammatory index and albumin serum levels potentially represent a sufficient early surrogate marker to detect patients at high risk of impaired OS better than complex conventional methods. These findings could help to identify patients who may benefit from early therapeutic interventions.

Open-Access Oesophagogastroduodenoscopy as an Effective and Safe Strategy for Patients With Non-alarming Symptoms.

Open-access oesophagogastroduodenoscopy (OAO) is defined as the performance of oesophagogastroduodenoscopy (OGD) requested by referring physicians without a prior specialist consultation. With the increasing demand for specialist appointments, the use of OAO has helped to reduce healthcare utilization by decreasing prior clinic visits. This also allows endoscopies to be scheduled and performed earlier. This study aims to evaluate our experience in providing OAO services to patients with non-alarming dyspepsia symptoms under the age of 60. The records of patients scheduled for OAO from January 2019 to December 2022 at Singapore General Hospital (SGH) Department of Gastroenterology were analyzed. Five hundred sixty-nine patients were scheduled for OAO, and 436 patients underwent the procedure. The mean age of patients was 45.7 (SD=10.9) years old. Thirty-six percent were males, and there were 80.8% Chinese, 5.3% Malay, 8.6% Indian, and 5.3% others. The median waiting time for endoscopy was 23 days (IQR 16-36), and no major adverse events were reported. Over half of the endoscopies were unremarkable (n=231, 53%). There were 25 (5.7%) patients with major findings; three had upper gastrointestinal adenocarcinoma (one oesophageal and two gastric), one had oesophageal varices, and 21 had peptic ulcer disease (10 gastric and 11 duodenal ulcers). A rapid urease test was conducted on 409 patients, and 55 (13.4%) were positive. OAO is a safe and effective strategy for providing timely diagnostic OGD to normal-risk patients at our center. Primary care physicians are encouraged to refer non-alarming dyspepsia symptoms patients under 60 years for OAO over the conventional route.

Exploring virulence factors of Helicobacter pylori isolated from gastric biopsy.

Helicobacter pylori (H. pylori) colonizes human gastric mucosa and is classified as class one carcinogenic bacteria. In this regard, this study aimed to detect major virulence factors in H. pylori strains recovered from gastric biopsy in patients referred to Aras Clinique in Ardabil, northwest of Iran (2019-2021). In this descriptive-cross sectional study, 287 dyspeptic patients were included. For bacterial isolation, gastric biopsy specimens (n=287) were taken from gastric antrum, then aseptically were cultured on the selective medium and incubated at 37C in microaerophilic conditions for 3-5 days. 25.18% of all (n = 70) patients were found to be infected withH. pylori uponendoscopy. Of them, 9 patients (12.857%) and 2 patients (2.875%) had peptic ulcer disease and gastric cancer respectively. According to the different patterns of virulence factors, 57 virutypes were identified in which oipA-vacAs1-vacAm2 (3, 4.28% n =) and oipA-vacAs1-vacAs2-vacAm2 (3, 4.28% n =) were the most common patterns. The simultaneous presence of vacAS2, vacAm2 and hopQ2 genes was observed in both patients with gastric cancer. OipA (n = 562.5%), VacAs1 (n = 6.75%), VacAs2 (n = 6.75%), and VacAm2 (n = 787.5%) were found to be the most prevalent virulence factor. According previous studies, it is confirmed that the cagPAI gene cluster and vacA gene alleles are strongly correlated with gastritis and gastrointestinal tract adenocarcinomas. Our study indicated that 50% of the indigenous strains of H. pylori harbor these oncogenic genes and they are hypervirulent.

Phase 2A trial of Ad5.F35-GUCY2C-PADRE vaccine for recurrence prevention in gastrointestinal (GI) adenocarcinomas post definitive surgery and adjuvant therapies.

TPS235 Background: A significant proportion of patients with GI adenocarcinomas remain at high risk of recurrence despite adjuvant therapies. Guanylyl cyclase C (GUCY2C) is expressed by normal intestinal cells and immunologically compartmentalized. Its overexpression in GI adenocarcinomas makes it an appealing target for anti-cancer therapies. We previously completed a phase I study of the Ad5-GUCY2C-PADRE vaccine in patients (pts) where it was safe and well tolerated (NCT01972737). Pre-existing neutralizing antibodies (NAbs) to the Ad5 vector opposed vaccine-induced immune responses. To overcome this challenge, we generated a GUCY2C vaccine employing a chimeric viral vector composed of the Ad5 capsid and Ad35 fiber protein (Ad5.F35). The extracellular domain of GUCY2C, along with the PADRE CD4+ helper T-cell epitope, were cloned into the Ad5.F35 viral vector to generate a replication-incompetent vaccine. Preclinical studies showed that Ad5.F35-GUCY2C-PADRE was less sensitive to pre-existing Ad5-specific immunity. Methods: This is a Phase 2A, dose-finding, single-center, open-label, randomized trial (NCT04111172) to evaluate the safety and immunogenic activity of three dose levels of Ad5.F35-GUCY2C-PADRE vaccine in adult pts with select solid tumors (colorectal, pancreatic, gastric, esophageal, or small bowel) who are at risk of relapse post definitive surgery and adjuvant therapy. Pts must enroll at 4-24 weeks from completion of standard therapies. Other key eligibility requirements include ECOG status of 0-1 and adequate organ function. Pts are randomized to one of three dose levels (1011 vp or viral particles, 1012 vp, or 5x1012 vp) with stratification by disease type. After completing an initial safety run-in for 9 pts (3 pts in each arm), the study will recruit up to 81 pts in total (27 in each arm). Pts will receive three successive doses of vaccine (4 weeks apart) and will undergo end-of-treatment assessment 4 weeks after their last vaccine. Pts are followed for disease status by scheduled follow-up until 2 years or recurrence, whichever occurs first. An interim futility analysis will be performed after 15 patients have completed treatment in each arm based on the Simon minimax design. Study objectives include assessment of safety and tolerability (primary), as well as T-cell and antibody responses to GUCY2C (secondary). Additional exploratory objectives include evaluating the relationship between NAbs and immune responses to GUCY2C, GUCY2C protein expression in tumors, circulating tumor DNA kinetics in relation to vaccination, and disease-free and overall survival (where applicable). Prespecified safety run-in has been completed without dose limiting toxicities; second stage accrual began in November 2021, and 43 out of 81 pts have been enrolled. Study enrollment is ongoing. Clinical trial information: NCT04111172 .

Inhibition of the renin-angiotensin system in patients with upper gastrointestinal adenocarcinoma.

Inhibition of the renin-angiotensin system in patients with upper gastrointestinal adenocarcinoma.

Investigating the causal relationship between gut microbiota and gastroenteropancreatic neuroendocrine neoplasms: a bidirectional Mendelian randomization study.

The interaction between the intestinal flora and gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) remains poorly understood, despite the known effect of the gut microbiota on gastrointestinal adenocarcinomas. Hence, the present research aimed to determine the potential causal correlation between the intestinal flora and GEP-NENs by conducting a bidirectional Mendelian randomization (MR) analysis. Two-sample MR analysis was conducted using the summary statistics of the gut microbiota from the MiBioGen consortium and those of GEP-NENs from the FinnGen research project. The inverse-variance weighted approach was utilized as the primary analytical method. To enhance the robustness of our findings, multiple sensitivity tests were performed, including Cochran's Q test for evaluating heterogeneity, the MR-Egger intercept test to detect horizontal pleiotropy, and the MR-PRESSO test to identify outliers and assess pleiotropy bias. Additionally, a leave-one-out analysis was performed to validate the consistency of our findings. The MR-Steiger test was also utilized to determine the causal direction in the correlation between the gut microbiota and GEP-NENs. Finally, a reverse MR analysis was performed to assess reverse causality between the intestinal flora and GEP-NENs. We identified 42 taxa of the gut microbiota that were potentially causally associated with GEP-NENs; of these taxa, 7, 8, 11, and 16 taxa were causally associated with pancreatic NENs, colorectal NENs, small intestinal NENs, and gastric NENs, respectively. After adjusting for false discovery rate (FDR) correction, we found significant causal links of Euryarchaeota with small intestinal NENs and Family XIII UCG-001 with gastric NENs. The sensitivity analyses confirmed the stability of these correlations. In the reverse MR analysis, colorectal NENs and small intestinal NENs were found to be associated with variations in 8 and 6 different taxa of the gut microbiota, respectively. After adjusting for FDR correction, no significant causal links were detected between GEP-NENs and the intestinal flora. The present study reveals a potential causal association between certain taxa of the intestinal flora and GEP-NENs, thus providing new perspectives regarding the role of the intestinal flora in the development of these tumors. These insights could provide innovative approaches to screen and prevent these diseases.