[Regarding the selection of individualized therapy after neoadjuvant therapy for gastrointestinal tumors].

Gastrointestinal tumors have been widely concerned because of increasing morbidity and mortality. In the process of exploring the therapeutic patterns of gastrointestinal tumors, patients treated with neoadjuvant therapies have good effect of tumor regression and favorable prognosis. Thus, neoadjuvant therapy strategies are recommended by major guidelines of gastrointestinal tumors in the world. Meanwhile, they have a great impact on the traditional methods of surgery, the influence mainly involves the reduction of the surgical margin and the scope of lymph node dissection in gastric cancer, while involves performing organ preservation and watch & wait in selective patients with colorectal cancer. These effects and changes were based on effective control of local recurrence by neoadjuvant therapies, and the advantages of neoadjuvant therapy in terms of tumor regression and survival supported by many studies. It is also based on the patient's desire for organ preservation and non-surgical treatment. Meanwhile, application of neoadjuvant therapy strategies increase surgical difficulty and postoperative complications, but the overall impact on patient prognosis is weak. Therefore, the selection of an appropriate treatment model after neoadjuvant therapy requires an effective overall post-treatment evaluation. In particular, it is necessary to pay attention to the evaluation of imaging, endoscopy, etc., while effectively performing monitoring and follow-up, and finally establishing an appropriate salvage treatment. This article will review the status and problems of individualized treatment after neoadjuvant therapy of gastrointestinal tumor.

[Clinical significance of immune checkpoint inhibitors in neoadjuvant therapy for gastric cancer].

Multiple prospective clinical studies have demonstrated that chemotherapy combined with immune checkpoint inhibitors (ICIs) can prolong the survival of patients with far-advanced gastric cancer. For patients with locally advanced gastric cancer (LAGC), preoperative neoadjuvant chemotherapy combined with immunotherapy has also achieved some encouraging results which benefit some patients, achieve clinical downstage, attenuate hidden metastases, increase R0 resection rate and reduce postoperative recurrence rate, etc. How to apply ICIs or combine immunotherapy with other therapies correctly in the course of neoadjuvant comprehensive treatment for patients with LAGC is still a very challenging and difficult problem. There are three basic principles in immunotherapy to be grasped: (1) Based on high-level clinical practice guidelines; (2) Based on the results of high-quality evidence-based medical research; and (3) Based on molecular pathology and tumor biomarkers. Perioperative immunotherapy for gastric cancer can be correctly applied if these three principles are organically integrated. Referring to the results of domestic and international clinical research in recent years, the three basic principles are demonstrated in this article for readers.

[The efficacy and safety of laparoscopic radical gastrectomy after neoadjuvant chemotherapy combined with immunotherapy and targeted therapy].

Objectives: To explore the efficacy and safety of laparoscopic radical gastrectomy after neoadjuvant chemotherapy combined with immunotherapy and targeted therapy in patients with gastric cancer. Methods: A retrospective analysis of clinical and pathological data of 20 patients with locally advanced gastric cancer (clinical TNM stage T3-4aN+M0) admitted to the Cancer Hospital, Chinese Academy of Medical Sciences from July 2021 to July 2023. All patients received 3 cycles of SOX (Oxaliplatin+S-1) regimen combined with immunotherapy (Trastuzumab) and targeted therapy (Apatinib) as neoadjuvant treatment followed by laparoscopic radical gastrectomy for gastric cancer. Surgical outcomes, postoperative pathological response, and postoperative recovery were observed. Quantitative data, except for age and operation time, were expressed using Median (range). Results: Among the 20 patients, there were 18 males and 2 females, aged 41 to 73 years [(60.6±9.7) years]. All 20 patients underwent laparoscopic surgical treatment after neoadjuvant therapy, with one patient undergoing laparoscopic conversion to open total gastrectomy with partial transverse colon resection due to tumor invasion into the transverse mesocolon. Eight patients underwent totally laparoscopic radical gastrectomy, all with Billroth Ⅱ+Braun anastomosis at the distal stomach. Eleven patients underwent laparoscopic-assisted radical gastrectomy, among which total gastrectomy with Roux-en-Y anastomosis was performed in ten cases, and proximal gastrectomy with esophagogastrostomy overlap anastomosis was performed in one case. The mean operation time for the 20 patients was (165.0±34.1) minutes; intraoperative blood loss was 80 (20-100) ml; and the number of lymph nodes retrieved was 68 (21-89). Postoperative pathological TNM staging revealed stage T0N0M0 in six cases, stage Ⅰ in two cases, stage Ⅱ in three cases, and stage Ⅲ in nine cases. Six patients (30.0%) achieved pathological complete response, and nine patients (45.0%) achieved significant pathological response. The median postoperative time to flatus was 4 (1-5) days; oral intake resumed after 3 (2-5) days; and the median length of hospital stay was 13 (6-19) days. One patient developed colonic anastomotic leakage with intra-abdominal infection, and one patient developed duodenal stump leakage with intra-abdominal infection, both classified as Clavien-Dindo grade 3A complications, and improved after treatment and discharged. One patient developed gastric paresis, and two patients developed pleural effusion, classified as Clavien-Dindo grade 2 complications, and improved after treatment and discharged. There were no deaths within 30 days after discharge. Conclusions: Laparoscopic radical gastrectomy for gastric cancer after neoadjuvant treatment with the SOX regimen combined with immunotherapy and targeted therapy is safe and feasible, with satisfactory short-term efficacy. However, there is an increase in overall surgical risk and difficulty, and it is recommended to be performed in experienced gastric cancer centers.

A degradome-related signature for predicting the prognosis and immunotherapy benefit in stomach adenocarcinoma based on machine learning procedure.

Stomach adenocarcinoma (STAD) is one of the subtype of gastric cancer with high invasiveness, extreme heterogeneity, high morbidity, and high mortality. The degradome is the most abundant class of cellular enzymes that play an essential role in regulating cellular activity and carcinogenesis. An integrative machine learning procedure including 10 methods was performed to develop a prognostic degradome-based prognostic signature (DPS) in TCGA, GSE15459, GSE26253, and GSE62254 datasets. Investigations of the DPS concerning immune infiltration, immunotherapy benefits, and drug priority were orchestrated. The DPS developed by Enet [alpha = 0.3] method was regarded as the optimal prognostic model. The DPS had a stable and powerful performance in predicting the clinical outcome of STAD and served as an independent risk factor in training and testing cohorts. The C-index of DPS was higher than that of age, sex, and clinical stage. STAD patients with low DPS scores had a higher abundance of B cells, CD8+ T cells, higher cytolytic scores, and T cell co-stimulation scores. Moreover, low DPS score indicated a lower tumor immune dysfunction and exclusion score, lower T cell dysfunction and exclusion score, higher PD1&CTLA4 immunophenoscore, and higher tumor mutation burden score in STAD, demonstrating a better immunotherapy response. STAD patients with a high DPS score had a lower IC50 value of common chemotherapy and targeted therapy regimens (Cisplatin, Docetaxel, Gefitinib, etc). Our study developed an optimal DPS for STAD. The DPS could predict the prognosis, risk stratification and guide treatment for STAD patients.

Integrated analysis of single-cell and bulk RNA-sequencing reveals a novel signature based on NK cell marker genes to predict prognosis and immunotherapy response in gastric cancer.

Natural killer (NK) cells play essential roles in the tumor development, diagnosis, and prognosis of tumors. In this study, we aimed to establish a reliable signature based on marker genes in NK cells, thus providing a new perspective for assessing immunotherapy and the prognosis of patients with gastric cancer (GC). We analyzed a total of 1560 samples retrieved from the public database. We performed a comprehensive analysis of single-cell RNA-sequencing (scRNA-seq) data of gastric cancer and identified 377 marker genes for NK cells. By performing Cox regression analysis, we established a 12-gene NK cell-associated signature (NKCAS) for the Cancer Genome Atlas (TCGA) cohort, that assigned GC patients into a low-risk group (LRG) or a high-risk group (HRG). In the TCGA cohort, the areas under curve (AUC) value were 0.73, 0.81, and 0.80 at 1, 3, and 5 years. External validation of the predictive ability for the signature was then validated in the Gene Expression Omnibus (GEO) cohorts (GSE84437). The expression levels of signature genes were measured and validated in GC cell lines by real-time PCR. Moreover, NKCAS was identified as an independent prognostic factor by multivariate analysis. We combined this with a variety of clinicopathological characteristics (age, M stage, and tumor grade) to construct a nomogram to predict the survival outcomes of patients. Moreover, the LRG showed higher immune cell infiltration, especially CD8+ T cells and NK cells. The risk score was negatively associated with inflammatory activities. Importantly, analysis of the independent immunotherapy cohort showed that the LRG had a better prognosis and immunotherapy response when compared with the HRG. The identification of NK cell marker genes in this study suggests potential therapeutic targets. Additionally, the developed predictive signatures and nomograms may aid in the clinical management of GC.

A radiomics signature derived from CT imaging to predict MSI status and immunotherapy outcomes in gastric cancer: a multi-cohort study.

BACKGROUND: Accurate microsatellite instability (MSI) testing is essential for identifying gastric cancer (GC) patients eligible for immunotherapy. We aimed to develop and validate a CT-based radiomics signature to predict MSI and immunotherapy outcomes in GC. METHODS: This retrospective multicohort study included a total of 457 GC patients from two independent medical centers in China and The Cancer Imaging Archive (TCIA) databases. The primary cohort (n = 201, center 1, 2017-2022), was used for signature development via Least Absolute Shrinkage and Selection Operator (LASSO) and logistic regression analysis. Two independent immunotherapy cohorts, one from center 1 (n = 184, 2018-2021) and another from center 2 (n = 43, 2020-2021), were utilized to assess the signature's association with immunotherapy response and survival. Diagnostic efficiency was evaluated using the area under the receiver operating characteristic curve (AUC), and survival outcomes were analyzed via the Kaplan-Meier method. The TCIA cohort (n = 29) was included to evaluate the immune infiltration landscape of the radiomics signature subgroups using both CT images and mRNA sequencing data. RESULTS: Nine radiomics features were identified for signature development, exhibiting excellent discriminative performance in both the training (AUC: 0.851, 95%CI: 0.782, 0.919) and validation cohorts (AUC: 0.816, 95%CI: 0.706, 0.926). The radscore, calculated using the signature, demonstrated strong predictive abilities for objective response in immunotherapy cohorts (AUC: 0.734, 95%CI: 0.662, 0.806; AUC: 0.724, 95%CI: 0.572, 0.877). Additionally, the radscore showed a significant association with PFS and OS, with GC patients with a low radscore experiencing a significant survival benefit from immunotherapy. Immune infiltration analysis revealed significantly higher levels of CD8 + T cells, activated CD4 + B cells, and TNFRSF18 expression in the low radscore group, while the high radscore group exhibited higher levels of T cells regulatory and HHLA2 expression. CONCLUSION: This study developed a robust radiomics signature with the potential to serve as a non-invasive biomarker for GC's MSI status and immunotherapy response, demonstrating notable links to post-immunotherapy PFS and OS. Additionally, distinct immune profiles were observed between low and high radscore groups, highlighting their potential clinical implications.

Real-world evidence of treatment patterns and survival of metastatic gastric cancer patients in Germany.

BACKGROUND: Patients with metastatic gastric cancer (mGC) have poor prognosis. This real-world study aimed to describe treatment regimens and survival of mGC patients. METHODS: A retrospective analysis was conducted using anonymized German claims data (AOK PLUS) covering a period from 2010 to 2021. The study population included newly diagnosed mGC cases identified from 2011 to 2020. The index date was defined as the first diagnosis of metastasis on or after gastric cancer diagnosis. Therapy regimens were identified based on inpatient and outpatient data, and subsequently stratified by line of treatment. Survival analyses were conducted using the Kaplan-Meier method. RESULTS: The cohort consisted of 5,278 mGC incident cases (mean age: 72.7 years; male: 61.9%). Nearly half of the incident cases received mGC-related treatment (49.8%). Treated patients were more often male, younger, and had fewer comorbidities compared to untreated patients. Of the 2,629 mGC patients who started the first line of treatment (1LOT), 32.8% switched to 2LOT, and 10.2% reached 3LOT. Longer survival time was observed among disease-specific treated cases compared with untreated cases (median real-world overall survival (rwOS): 12.7 months [95%CI 12.1 - 13.3 months] vs. 3.7 months [95%CI 3.4 - 4.0 months]). CONCLUSION: Systemic therapy was not received in almost half of the mGC patients. In those patients, a very short median rwOS was observed. Treatment patterns were generally in line with the guideline recommendations, however, therapy switching rates and poor prognosis indicate high unmet needs also in the treated population.

Liquid biopsy for gastric cancer: Techniques, applications, and future directions.

After the study of circulating tumor cells in blood through liquid biopsy (LB), this technique has evolved to encompass the analysis of multiple materials originating from the tumor, such as nucleic acids, extracellular vesicles, tumor-educated platelets, and other metabolites. Additionally, research has extended to include the examination of samples other than blood or plasma, such as saliva, gastric juice, urine, or stool. LB techniques are diverse, intricate, and variable. They must be highly sensitive, and pre-analytical, patient, and tumor-related factors significantly influence the detection threshold, diagnostic method selection, and potential results. Consequently, the implementation of LB in clinical practice still faces several challenges. The potential applications of LB range from early cancer detection to guiding targeted therapy or immunotherapy in both early and advanced cancer cases, monitoring treatment response, early identification of relapses, or assessing patient risk. On the other hand, gastric cancer (GC) is a disease often diagnosed at advanced stages. Despite recent advances in molecular understanding, the currently available treatment options have not substantially improved the prognosis for many of these patients. The application of LB in GC could be highly valuable as a non-invasive method for early diagnosis and for enhancing the management and outcomes of these patients. In this comprehensive review, from a pathologist's perspective, we provide an overview of the main options available in LB, delve into the fundamental principles of the most studied techniques, explore the potential utility of LB application in the context of GC, and address the obstacles that need to be overcome in the future to make this innovative technique a game-changer in cancer diagnosis and treatment within clinical practice.

TOB1 modulates neutrophil phenotypes to influence gastric cancer progression and immunotherapy efficacy.

Introduction: The ErbB-2.1(TOB1) signaling transducer protein is a tumor-suppressive protein that actively suppresses the malignant phenotype of gastric cancer cells. Yet, TOB1 negatively regulates the activation and growth of different immune cells. Understanding the expression and role of TOB1 in the gastric cancer immune environment is crucial to maximize its potential in targeted immunotherapy. Methods: This study employed multiplex immunofluorescence analysis to precisely delineate and quantify the expression of TOB1 in immune cells within gastric cancer tissue microarrays. Univariate and multivariate Cox analyses were performed to assess the influence of clinical-pathological parameters, immune cells, TOB1, and double-positive cells on the prognosis of gastric cancer patients. Subsequent experiments included co-culture assays of si-TOB1-transfected neutrophils with AGS or HGC-27 cells, along with EdU, invasion, migration assays, and bioinformatics analyses, aimed at elucidating the mechanisms through which TOB1 in neutrophils impacts the prognosis of gastric cancer patients. Results: We remarkably revealed that TOB1 exhibits varying expression levels in both the nucleus (nTOB1) and cytoplasm (cTOB1) of diverse immune cell populations, including CD8+ T cells, CD66b+ neutrophils, FOXP3+ Tregs, CD20+ B cells, CD4+ T cells, and CD68+ macrophages within gastric cancer and paracancerous tissues. Significantly, TOB1 was notably concentrated in CD66b+ neutrophils. Survival analysis showed that a higher density of cTOB1/nTOB1+CD66b+ neutrophils was linked to a better prognosis. Subsequent experiments revealed that, following stimulation with the supernatant of tumor tissue culture, the levels of TOB1 protein and mRNA in neutrophils decreased, accompanied by enhanced apoptosis. HL-60 cells were successfully induced to neutrophil-like cells by DMSO. Neutrophils-like cells with attenuated TOB1 gene expression by si-TOB1 demonstrated heightened apoptosis, consequently fostering a malignant phenotype in AGS and HCG-27 cells upon co-cultivation. The subsequent analysis of the datasets from TCGA and TIMER2 revealed that patients with high levels of TOB1 combined neutrophils showed better immunotherapy response. Discussion: This study significantly advances our comprehension of TOB1's role within the immune microenvironment of gastric cancer, offering promising therapeutic targets for immunotherapy in this context.

The viral etiology of EBV-associated gastric cancers contributes to their unique pathology, clinical outcomes, treatment responses and immune landscape.

Epstein-Barr virus (EBV) is a pathogen known to cause a number of malignancies, often taking years for them to develop after primary infection. EBV-associated gastric cancer (EBVaGC) is one such malignancy, and is an immunologically, molecularly and pathologically distinct entity from EBV-negative gastric cancer (EBVnGC). In comparison with EBVnGCs, EBVaGCs overexpress a number of immune regulatory genes to help form an immunosuppressive tumor microenvironment (TME), have improved prognosis, and overall have an "immune-hot" phenotype. This review provides an overview of the histopathology, clinical features and clinical outcomes of EBVaGCs. We also summarize the differences between the TMEs of EBVaGCs and EBVnGCs, which includes significant differences in cell composition and immune infiltration. A list of available EBVaGC and EBVnGC gene expression datasets and computational tools are also provided within this review. Finally, an overview is provided of the various chemo- and immuno-therapeutics available in treating gastric cancers (GCs), with a focus on EBVaGCs.

Gastric neuroendocrine neoplasms.

Gastric neuroendocrine neoplasms (gNENs) display peculiar site-specific features among all NENs. Their incidence and prevalence have been rising in the past few decades. gNENs comprise gastric neuroendocrine carcinomas (gNECs) and gastric neuroendocrine tumours (gNETs), the latter further classified into three types. Type I anatype II gNETs are gastrin-dependent and develop in chronic atrophic gastritis and as part of Zollinger-Ellison syndrome within a multiple endocrine neoplasia type 1 syndrome (MEN1), respectively. Type III or sporadic gNETs develop in the absence of hypergastrinaemia and in the context of a near-normal or inflamed gastric mucosa. gNECs can also develop in the context of variable atrophic, relatively normal or inflamed gastric mucosa. Each gNEN type has different clinical characteristics and requires a different multidisciplinary approach in expert dedicated centres. Type I gNETs are managed mainly by endoscopy or surgery, whereas the treatment of type II gNETs largely depends on the management of the concomitant MEN1. Type III gNETs may require both locoregional approaches and systemic treatments; NECs are often metastatic and therefore require systemic treatment. Specific data regarding the systemic treatment of gNENs are lacking and are derived from the treatment of intestinal NETs and NECs. An enhanced understanding of molecular and clinical pathophysiology is needed to improve the management and outcomes of patients' gNETs.

A prospective phase II clinical trial of total neoadjuvant therapy for locally advanced gastric cancer and gastroesophageal junction adenocarcinoma.

To investigate the safety and efficacy of the neoadjuvant chemoradiotherapy (NCRT) followed by neoadjuvant consolidation chemotherapy (NCCT) and surgery for locally advanced gastric cancer (GC) or gastroesophageal junction (GEJ) adenocarcinoma. Patients diagnosed as locally advanced GC or Siewert II/III GEJ adenocarcinoma with clinical stage T3-4 and/or N positive were prospectively enrolled. Patients underwent NCRT (45 Gy/25 fractions) with concurrent S-1, followed by NCCT (4 to 6 cycles of the SOX regimen) 2 to 4 weeks after NCRT. Gastric cancer radical resection with D2 lymph node dissection was performed 4 to 6 weeks after the total neoadjuvant therapy. The study was conducted from November 2019 to January 2023, enrolling a total of 46 patients. During the NCRT, all patients completed the treatment without dose reduction or delay. During the NCCT, 32 patients (69.6%) completed at least 4 cycles of chemotherapy. Grade 3 or higher adverse events in NCRT (5 cases) were non-hematological. During the course of NCCT, a notable occurrence of hematological toxicities was observed, with grade 3 or higher leukopenia (9.7%) and thrombocytopenia (12.2%) being experienced. A total of 28 patients (60.9%) underwent surgery, achieving R0 resection in all cases. A significant proportion of cases (71.4%) exhibited pathological downstaging to ypT0-2, while 10 patients (35.7%) demonstrated a pathologic complete response (pCR). The total neoadjuvant therapy comprising NCRT followed by NCCT and surgery demonstrates a low severe adverse reactions and promising efficacy, which could be considered as a viable treatment for locally advanced GC or GEJ adenocarcinoma.Trial registration: Clinicaltrials.gov (registration number: NCT04062058); the full date of first trial registration was 20/08/2019.

Carcinoma stomach in Eastern India-An audit from a tertiary health care center.

BACKGROUND: In spite of declining incidence and fatality over the past decade, stomach cancer still remains a global health issue due to its aggressiveness and heterogeneity. There is wide variation in the epidemiology of stomach cancer, not only worldwide but also among different regions of India. However, there is very limited data available for the Indian population. AIMS AND OBJECTIVE: This study was aimed at establishing the incidence and role of risk factors, analyzing the symptoms, stage of disease, and mode of various surgical treatments of patients in the eastern region of India, and comparing them with the results of other studies in India and regions outside India. METHODS AND MATERIAL: An audit of the database of carcinoma stomach patients attending the radiotherapy and surgery outpatient department (OPD) between January 2020 and June 2021 was performed. Demographic, clinical, and treatment-related data were collected and analyzed with respect to other regions of India and the worldwide pattern of carcinoma stomach. RESULTS: The mean age of the study population was 58 years with male dominance (70%). The antrum was the most common (60%) primary site, and stage III was the most common (47.6%) stage at presentation. Around 73.4% of patients underwent radical surgery. Most patients (50%) had an eventless post-operative period, and 76% received peri-operative chemotherapy. Also, 20% of patients received adjuvant chemoradiation. CONCLUSION: Our analysis suggests that there are certain differences (like dietary habits), as well as similarities (like socio-demographic factors), among the risk factors of carcinoma in this part of the country than other parts. Further studies into the risk factors and different clinical presentations are required for prevention and early detection.

GC-CDSS: Personalized gastric cancer treatment recommendations system based on knowledge graph.

BACKGROUND: Gastric cancer (GC) is one of the most common malignant tumors in the world, posing a serious threat to human health. Currently, gastric cancer treatment strategies emphasize a multidisciplinary team (MDT) consultation approach. However, there are numerous treatment guidelines and insights from clinical trials. The application of AI-based Clinical Decision Support System (CDSS) in tumor diagnosis and screening is increasing rapidly. OBJECTIVE: The purpose of this study is to (1) summarize the treatment decision process for GC according to the treatment guidelines in China, and then create a knowledge graph (KG) for GC, (2) based on aforementioned KG, built a CDSS and conducted an initial feasibility evaluation for the current system. METHODS: Firstly, we summarized the decision-making process for treatment of GC. Then, we extracted relevant decision nodes and relationships and utilized Neo4j to create the KG. After obtaining the initial node features for building the graph embedding model, graph embedding algorithm, such as Node2Vec and GraphSAGE, were used to construct the GC-CDSS. At last, a retrospective cohort study was used to compare the consistency between GC-CDSS and MDT in treatment decision making. RESULTS: In current study, we introduce a GC-CDSS, which is constructed based on Chinese GC treatment guidelines knowledge graph (KG). In the KG, we define four types of nodes and four types of relationships, and it comprise a total of 207 nodes and 300 relationships. Regarding GC-CDSS, the system is capable of providing dynamic and personalized diagnostic and treatment recommendations based on the patient's condition. Furthermore, a retrospective cohort study is conducted to compare GC-CDSS recommendations with those of the MDT group, the overall consistency rate of treatment recommendations between the auxiliary decision system and MDT team is 92.96%. CONCLUSIONS: We construct a GC treatment support system, GC-CDSS, based on KG. The GC-CDSS may help oncologists make treatment decisions more efficient and promote standardization in primary healthcare settings.

Chinese national clinical practice guidelines on the prevention, diagnosis, and treatment of early gastric cancer.

BACKGROUND: Gastric cancer is one of the most common malignant tumors in the digestive system in China. Few comprehensive practice guidelines for early gastric cancer in China are currently available. Therefore, we created the Chinese national clinical practice guideline for the prevention, diagnosis, and treatment of early gastric cancer. METHODS: This clinical practice guideline (CPG) was developed in accordance with the World Health Organization's recommended process and with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) in assessing evidence quality. We used the Evidence to Decision framework to formulate clinical recommendations to minimize bias and increase transparency in the CPG development process. We used the Reporting Items for practice Guidelines in HealThcare (RIGHT) statement and the Appraisal of Guidelines for Research and Evaluation II (AGREE II) as reporting and conduct guidelines to ensure completeness and transparency of the CPG. RESULTS: This CPG contains 40 recommendations regarding the prevention, screening, diagnosis, treatment, and follow-up of early gastric cancer based on available clinical studies and guidelines. We provide recommendations for the timing of Helicobacter pylori eradication, screening populations for early gastric cancer, indications for endoscopic resection and surgical gastrectomy, follow-up interval after treatment, and other recommendations. CONCLUSIONS: This CPG can lead to optimum care for patients and populations by providing up-to-date medical information. We intend this CPG for widespread adoption to increase the standard of prevention, screening, diagnosis, treatment, and follow-up of early gastric cancer; thereby, contributing to improving national health care and patient quality of life.

Analyzing the associations between tertiary lymphoid structures and postoperative prognosis, along with immunotherapy response in gastric cancer: findings from pooled cohort studies.

BACKGROUND: The clinical significance of tertiary lymphoid structure (TLS) in gastric cancer (GC) was uncertain. METHODS: A systematic search was performed in public databases for eligible studies as of April 2, 2023. Meta-analyses were performed to interrogate the associations between TLS levels and prognosis and immunotherapy response of GC. Bioinformatic analyses based on the nine-gene signature of TLS were further conducted to capture the biological underpinnings. RESULTS: Eleven studies containing 4224 GC cases were enrolled in the meta-analysis. TLS levels positively correlated with smaller tumor size, earlier T stage and N stage. Moreover, higher TLS levels were detected in diffuse and mix subtypes of GC (P < 0.001). Higher TLS levels strongly predicted favorable postoperative overall survival of GC, with HR of 0.36 (95%CI 0.26-0.50, P < 0.001) and 0.55 (95%CI 0.45-0.68, P < 0.001) of univariate and multivariate Cox analysis, respectively. Higher TLS levels were also in favor of the treatment response of anti-PD-1 inhibitors as later-line therapy of GC. TLS levels positively correlated with immune effector cells infiltration, diversity and richness of T cell receptor and B cell receptor repertoire, immune checkpoint genes expression, and immune-related genes mutation of GC in the TCGA-STAD cohort, representing higher immunogenicity and immunoactivity. Moreover, moderate accuracy of TLS levels in predicting benefit from anti-PD-1 inhibitors in the PRJEB25780 cohort was also validated (AUC 0.758, 95%CI 0.583-0.933), higher than the microsatellite instability-score and Epstein-Barr virus status. CONCLUSIONS: TLS levels demonstrated potential in predicting the postoperative prognosis and immunotherapy response of GC.

Multimodal management of foregut neuroendocrine neoplasms.

The foregut, which includes the esophagus, stomach and duodenum, represents one of the most common sites for neuroendocrine neoplasms. These are highly heterogenous with different risk of progression depending on location, cell-type of origin, size, grade and other factors. Various endoscopic and imaging modalities exist to inform therapeutic decision-making, which may be in the form of surgical or endoscopic resection and medical therapy depending on the extent of the disease after diagnostic evaluation. This narrative review aims to explore the literature on the multimodal management of such foregut neuroendocrine neoplasms.

Construction of a gene model related to the prognosis of patients with gastric cancer receiving immunotherapy and exploration of COX7A1 gene function.

BACKGROUND: GC is a highly heterogeneous tumor with different responses to immunotherapy, and the positive response depends on the unique interaction between the tumor and the tumor microenvironment (TME). However, the currently available methods for prognostic prediction are not satisfactory. Therefore, this study aims to construct a novel model that integrates relevant gene sets to predict the clinical efficacy of immunotherapy and the prognosis of GC patients based on machine learning. METHODS: Seven GC datasets were collected from the Gene Expression Omnibus (GEO) database, The Cancer Genome Atlas (TCGA) database and literature sources. Based on the immunotherapy cohort, we first obtained a list of immunotherapy related genes through differential expression analysis. Then, Cox regression analysis was applied to divide these genes with prognostic significancy into protective and risky types. Then, the Single Sample Gene Set Enrichment Analysis (ssGSEA) algorithm was used to score the two categories of gene sets separately, and the scores differences between the two gene sets were used as the basis for constructing the prognostic model. Subsequently, Weighted Correlation Network Analysis (WGCNA) and Cytoscape were applied to further screen the gene sets of the constructed model, and finally COX7A1 was selected for the exploration and prediction of the relationship between the clinical efficacy of immunotherapy for GC. The correlation between COX7A1 and immune cell infiltration, drug sensitivity scoring, and immunohistochemical staining were performed to initially understand the potential role of COX7A1 in the development and progression of GC. Finally, the differential expression of COX7A1 was verified in those GC patients receiving immunotherapy. RESULTS: First, 47 protective genes and 408 risky genes were obtained, and the ssGSEA algorithm was applied for model construction, showing good prognostic discrimination ability. In addition, the patients with high model scores showed higher TMB and MSI levels, and lower tumor heterogeneity scores. Then, it is found that the COX7A1 expressions in GC tissues were significantly lower than those in their corresponding paracancerous tissues. Meanwhile, the patients with high COX7A1 expression showed higher probability of cancer invasion, worse clinical efficacy of immunotherapy, worse overall survival (OS) and worse disease-free survival (DFS). CONCLUSIONS: The ssGSEA score we constructed can serve as a biomarker for GC patients and provide important guidance for individualized treatment. In addition, the COX7A1 gene can accurately distinguish the prognosis of GC patients and predict the clinical efficacy of immunotherapy for GC patients.