Gastrointestinal cancers including esophageal squamous cell carcinoma (ESCC), gastric cancer (GC), and colorectal cancer (CRC) are common and highly lethal types of cancer worldwide. Metabolic reprogramming plays a critical role in cancer progression and involves metabolic processes such as glucose and lipid metabolism. Fatty acid oxidation (FAO) has a profound impact on cancer, with many genes and cytokines influencing cancer cell initiation, development, metastasis, and resistance by regulating FAO. Additionally, FAO further promotes cancer progression by affecting the tumor microenvironment (TME). The role of FAO in gastrointestinal cancers has garnered increasing attention, and related anticancer drugs are currently being developed.

Background and Objectives: Venous thromboembolism (VTE) is a serious complication frequently encountered in cancer patients and is associated with high morbidity. In patients undergoing cancer treatment-particularly those receiving chemotherapy-VTE increases treatment-related complications and has a direct impact on mortality. The development of VTE in oncology patients varies depending on cancer type, treatment protocols, and individual patient characteristics. The Khorana Risk Score (KRS) is a validated risk assessment tool used to estimate the risk of VTE development in patients receiving chemotherapy. KRS provides risk estimations based on the patient's clinical features, cancer type, and treatment process. This study aims to investigate the prognostic value of the Khorana Risk Score in predicting VTE development and overall survival in patients with metastatic gastric cancer. Materials and Methods: This retrospective study used data from 337 metastatic gastric cancer patients who presented to Kartal Dr. Lütfi Kırdar City Hospital between January 2012 and June 2024. Patients were categorized into intermediate- and high-risk groups according to the Khorana Risk Score. The study's primary endpoints were the development of VTE and overall survival. Results: There was no statistically significant difference in VTE incidence (p = 0.27) or overall survival (11.9 months vs. 11.5 months, p = 0.23) between patients in the intermediate- and high-risk groups. Conclusions: These results indicate that the Khorana Risk Score is insufficient in predicting VTE development in patients with metastatic gastric cancer and has a weak association with overall survival outcomes. In conclusion, this study demonstrates the KRS's inadequacy in predicting VTE and survival outcomes in patients with metastatic gastric cancer, highlighting the need for more tailored approaches.

Deficiency in DNA mismatch repair (dMMR) is a common pathway of carcinogenesis across different tumour types and confers a characteristic microsatellite instability-high (MSI-H) molecular phenotype. The prevalence of the MSI-H/dMMR phenotype is highest in endometrial and colorectal cancers, and this phenotype is associated with a distinct tumour biology, prognosis and responsiveness to various anticancer treatments. In a minority of patients, MSI-H/dMMR cancers result from an inherited pathogenic variant in the context of Lynch syndrome, which has important implications for familial genetic screening. Whether these hereditary cancers have a different biology and clinical behaviour to their sporadic counterparts remains uncertain. Interest in this tumour molecular subtype has increased following the discovery of the high sensitivity of metastatic MSI-H/dMMR cancers to immune-checkpoint inhibitors (ICIs) in a histology-agnostic manner, which reflects the genomic hypermutation resulting from dMMR that renders these tumours highly immunogenic and immune infiltrated. This vulnerability is now also being exploited in early stage disease settings. Despite this common biological foundation, different MSI-H/dMMR cancers have histotype-specific features that correspond to their particular cell or tissue of origin, which might be associated with differences in prognosis and sensitivity to ICIs. In this Review, we provide an overview of the epidemiology, biology, pathogenesis, clinical diagnosis and treatment of MSI-H/dMMR tumours as a histology-agnostic cancer phenomenon. We also highlight peculiarities associated with specific pathogenetic alterations and histologies of MSI-H/dMMR tumours.

Gastric cancer arises from complex carcinogenic factor interactions, with limited treatment options due to the lack of targetable driver gene mutations and significant tumor heterogeneity. Recent studies have provided promising novel approaches to improve our understanding of gastric cancer heterogeneity through integrated characterization, combining genomics with emerging technologies. Delineating the molecular changes and targeting specific molecular subtypes will enhance the efficacy of gastric cancer treatment and improve clinical outcomes. This review provides a comprehensive overview of current technologies used in gastric cancer research, highlighting key discoveries and treatment strategies driven by these innovations. Finally, we discuss the emerging technology-guided directions and potential breakthroughs that could enhance the understanding of gastric cancer tumor heterogeneity, ultimately improving clinical outcomes.

We aimed to assess the real-world effectiveness and safety of pembrolizumab monotherapy in Japanese patients with high-frequency microsatellite instability (MSI-H) solid tumors except colorectal cancer.

This multicenter, observational, post-marketing surveillance had a 12-month observation period. We included all patients with locally advanced or metastatic MSI-H solid tumors, except colorectal cancer, in whom standard treatment was difficult or who had shown tumor progression after conventional chemotherapies and had started treatment with pembrolizumab by 31 December 2019.

In total, 403 patients were enrolled, and 396 and 376 patients were included in the safety and effectiveness analysis sets, respectively. The numbers of patients and frequencies of tumor types occurring in ≥20 cases were: endometrial, 162/403 (40.2%); gastric, 61/403 (15.1%); biliary tract, 42/403 (10.4%); pancreatic, 29/403 (7.2%); and ovarian, 20/403 (5.0%). The objective response rate was 50.3% (189/376) and the disease control rate was 71.5% (269/376). The 12-month progression-free survival (PFS) rate was 42.1% and the median PFS was 8.8 months (95% confidence interval, 6.4-11.5). The 12-month overall survival (OS) rate was 75.1%, and median OS was not reached. Treatment-related adverse events (AEs) of special interest of any grade occurred in 128/396 (32.3%) patients, and those of Grade ≥ 3, in 54/396 (13.6%) patients. One patient with esophageal cancer experienced a Grade 5 AE. No new safety signals were observed.

This study confirmed the real-world effectiveness and safety of pembrolizumab monotherapy in patients with MSI-H solid tumors except colorectal cancer in Japan.

Gastric cancer (GC) is one of the primary contributors to cancer-related mortality on a global scale. It holds a position within the top five most prevalent malignancies both in terms of occurrence and fatality rates. Immunotherapy, as a breakthrough cancer treatment, brings new hope for GC patients. Various biomarkers, such as the expression of programmed death ligand-1 (PD-L1), the microsatellite instability (MSI) status, tumor mutational burden (TMB), and Epstein-Barr virus (EBV) infection, demonstrate potential to predict the effectiveness of immunotherapy in treating GC. Nevertheless, each biomarker has its own limitations, which leads to a significant portion of patients continue to be unresponsive to immunotherapy. With the understanding of the tumor immune microenvironment (TIME), genome sequencing technology, and recent advances in molecular biology, new molecular markers, such as POLE/POLD1mutations, circulating tumor DNA, intestinal flora, lymphocyte activation gene 3 (LAG-3), and lipid metabolism have emerged. This review aims to consolidate clinical evidence to offer a thorough comprehension of the existing and emerging biomarkers. We discuss the mechanisms, prospects of application, and limitations of each biomarker. We anticipate that this review will open avenues for fresh perspectives in the investigation of GC immunotherapy biomarkers and promote the precise choice of treatment modalities for gastric cancer patients, thereby advancing precision immuno-oncology endeavors.

Identifying predictive biomarkers for immune checkpoint inhibitor (ICI) treatment is critical for gastric cancer (GC) prognosis. C-X-C motif chemokine ligand 13(CXCL13) plays an important role in immune regulation by binding exclusively to its receptor CXCR5. However, its role, underlying mechanisms, and prognostic significance in ICI-treated GC patients remain controversial.

This study investigated the clinical significance of CXCL13 and its potential immunomodulatory function in GC patients. A total of 144 GC patients from two cohorts, who received a combination of chemotherapy and anti-PD-1 antibody, were analyzed. The expression of CXCL13 was assessed using immunohistochemistry (IHC) and enzyme-linked immunosorbent assay. Associations between CXCL13, CXCR5, CD8, and CD4 were assessed by IHC and immunofluorescence. Survival analysis was performed using the Kaplan-Meier method and Cox proportional hazards model. The treatment response to CXCL13 and anti-PD-1 antibody was investigated using a subcutaneous xenograft tumor mouse model.

The results suggested that patients with high CXCL13 expression had prolonged survival. High CXCL13 expression exhibited increased infiltration of CXCR5+CD8+ T cells and was associated with better outcomes. The combined assessment of CXCL13, CXCR5, and CD8+ T cells served as an independent predictor of prognosis. Additionally, CXCR5 and CD8+ T cells were enriched in tertiary lymphoid structures (TLSs), which conferred a prognostic benefit in the presence of high CXCL13 expression. CXCL13, in combination with anti-PD-1 therapy, retarded tumor growth in vivo, resulting in increased infiltration of CXCR5+CD8+ T cells.

This study identified CXCL13 as a prognostic factor in GC patients receiving ICI therapy, emphasizing its critical role in the antitumor microenvironment via CXCR5+CD8+ T cells.

As one of the most common gastrointestinal tumors, Gastric Cancer (GC) poses a serious threat to human health due to its high morbidity and mortality. The current treatment strategy is a comprehensive treatment program mainly based on surgery, especially for advanced GC patients. The emergence of immune checkpoint inhibitors has completely changed this status quo, and the synergistic effect of neoadjuvant immunotherapy combined with chemotherapy has significantly improved the resection and radical rate and overall survival of patients with advanced local GC. We present a case of locally advanced GC (cT4N0Mx) with microsatellite instability high (MSI-H) and PD-L1 Combined Positive Score (CPS)=2. The patient received neoadjuvant therapy with Sintilimab combined with FOLFOX (folinic acid (leucovorin), 5-fluorouracil (5-FU), and oxaliplatin), and significantly reduced tumor volume after 3 cycles of treatment. Then she underwent subtotal gastrectomy with gastrojejunostomy and D2 lymph node dissection. The postoperative pathological results showed that no cancerous tissue remained in the tumor tissue, and pathologic complete response (pCR) was achieved. The first cycle of adjuvant therapy with the same protocol was received after surgery. During adjuvant therapy, patients mainly experienced side effects such as dyspepsia, nausea and mild myelosuppression. Therefore, immunotherapy with Sintilimab combined with FOLFOX chemotherapy has the potential to be an effective treatment option for patients with resectable locally advanced MSI-H GC.

The incorporation of immunotherapy has transformed the treatment landscape for advanced, unresectable, or metastatic gastroesophageal cancers (GECs), with improved survival outcomes. These improvements in outcomes for advanced GECs have led to clinical trials evaluating the role of immunotherapy in patients with resectable early-stage GECs. However, there remains a high burden of morbidity and mortality, and ongoing trials utilizing novel immunotherapy agents and combinations are underway. This review summarizes the findings of previous and ongoing clinical trials related to immunotherapy for patients with early- and late-stage GECs.

Tislelizumab plus investigator-chosen chemotherapy (ICC) demonstrated a statistically significant improvement in overall survival (OS) versus placebo plus ICC in RATIONALE-305 in patients with locally advanced unresectable or metastatic human epidermal growth factor receptor 2 (HER2)-negative gastric cancer/gastroesophageal junction cancer (GC/GEJC) in the intent-to-treat population and in patients with programmed death-ligand 1 (PD-L1) Tumor Area Positivity (TAP) score ≥ 5%. The United States Food and Drug Administration Oncologic Drugs Advisory Committee voted (September 2024) against first-line treatment with programmed cell death protein-1 inhibitors in this setting in patients with a PD-L1 combined positive score < 1 or TAP score < 1%, due to an unfavorable benefit-risk profile. Thus, we retrospectively analyzed data from RATIONALE-305 in patients with a PD-L1 TAP score ≥ 1%.

Adult patients with locally advanced unresectable or metastatic HER2-negative GC/GEJC were randomized to tislelizumab 200 mg or placebo with ICC every 3 weeks. Efficacy and safety outcomes of tislelizumab plus ICC versus placebo plus ICC were retrospectively assessed in those with a PD-L1 TAP score ≥ 1%.

At the final analysis cutoff (February 28, 2023), 432 patients received tislelizumab plus ICC and 453 received placebo plus ICC, and had a PD-L1 TAP score ≥ 1%. Clinically meaningful improvements to OS were observed with tislelizumab plus ICC compared with placebo plus ICC [15.0 months (95% confidence interval [CI] 13.3-16.7) vs. 12.8 months (95% CI 12.1-14.1), respectively; stratified hazard ratio 0.77 (95% CI 0.67-0.90)]. Progression-free survival, overall response rate, duration of response, and disease control rate, were also improved. OS improvements were maintained at a 3-year data cutoff (February 28, 2024). Tislelizumab plus ICC had an acceptable safety profile with no new safety signals.

Tislelizumab plus ICC is an effective and tolerable first-line treatment for patients with locally advanced unresectable or metastatic HER2-negative GC/GEJC with a PD-L1 TAP score ≥ 1%.

NCT03777657.

Gastric cancer remains a major health challenge worldwide, with nearly 1 million new cases annually contributing to more than 650 000 deaths. Epidemiologically, gastric cancer shows substantial geographical variation in incidence, with higher rates in Asia, South America, and eastern Europe, and a rapid increase in early-onset cases among people younger than 50 years. Key risk factors for gastric cancer include Helicobacter pylori infection, diet, obesity, smoking, and genetic predisposition. Early detection through comprehensive diagnostic procedures is crucial for optimising treatment outcomes. Standard treatment approaches for locally advanced gastric cancer include surgical resection, particularly D2 lymphadenectomy, complemented by chemotherapy and radiotherapy. There is increasing implementation of minimally invasive surgical techniques for operable disease and integration of immune checkpoint inhibitors and targeted therapies for advanced stages. Emerging therapies, such as novel targeted treatments and next-generation immunotherapies, show promise in improving survival and quality of life. Future directions in the management of gastric cancer focus on precision medicine, continued advancement in immunotherapy, novel early detection methods, and a multidisciplinary approach to care. These strategies aim to enhance the overall effectiveness of treatment and prognosis worldwide.

To explore the predictive value of the combined positive score (CPS) and the neutrophil-to- platelet count ratio (NPR) for surgical pathological remission in patients with locally advanced head and neck squamous cell carcinoma (LAHNSCC) who have undergone neoadjuvant immunotherapy combined with chemotherapy (NICC).

Patients with LAHNSCC who underwent NICC and surgery from May 2021 to September 2023 were retrospectively analyzed. CPS, NPR and other clinically relevant parameters were collected, which includes gender, age, tumor types, multiple cancer, differentiation, T staging, N staging, immunotherapy cycles and postoperative pathological remission degree.

Patients with a higher CPS were significantly associated with a higher pathological complete response (PCR) of the primary site (PPCR) (P = 0.034) and a higher PCR of the lymph nodes (LPCR) (P = 0.085). Specifically, patients with a CPS of ≥20 demonstrated a higher rate of severe pathologic tumor response (PTR), with values of 80.8% compared to 66.7% and 50%. Notably, even patients with a CPS <1 had a relatively high severe PTR rate of 66.7%. Moreover, patients with NPR <0.024 exhibited a higher severe PTR, regardless of the CPS subgroups (P < 0.05).

Higher CPS can be considered a good predictor of higher PCR after NICC in patients with LAHNSCC. Patients with CPS <1 can still achieve a higher PTR. Patients with NPR <0.024 can help achieve a higher severe PTR in patients with LAHNSCC regardless of the CPS.CPS combined with NPR may have a better predicted value for surgical PTR of HNSCC after NICC.

Gastric cancer peritoneal metastasis (GCPM) typically indicates a poor clinical prognosis and is frequently observed in diffuse gastric cancer (GC) patients with CDH1 loss of function. GCPM characterized for its aggressiveness and resistance to chemotherapy, most notably paclitaxel (PTX), poses significant treatment challenges. Previously, no mouse gastric adenocarcinoma (MGA) cell lines with Trp53 (encoding mouse p53) and Cdh1 (encoding mouse E-cadherin) mutations and a high potential for peritoneal metastasis in mice have been established. Here, we derived a mouse GC cell line, called MTC, from subcutaneously transplanted mouse Trp53-/-Cdh1-/- GC organoids. Through matching the short tandem repeat profile of MTC with those in current cell banks, we verified the uniqueness of MTC. Furtherly, we confirmed the features of MTC by detecting the expression of p53, E-cadherin, and pan-CK. After long-term exposure of the original MTC line to PTX, we developed a more aggressive, PTX-resistant cell line, termed MTC-R. Compared with MTC, MTC-R demonstrated enhanced tumorigenicity and high potential for peritoneal metastasis in subcutaneous and intraperitoneal tumour models both in BALB/c nude mice and C57BL/6 J mice. Transcriptome analysis revealed the ECM‒receptor interaction pathway activation during the development of PTX resistance, and dasatinib (DASA) was identified as a potential drug targeting this pathway. DASA showed promise in ameliorating disease progression and improving overall survival in MTC-R GCPM model in C57BL/6 J mice. Overall, we established a novel MGA cell line with Trp53 and Cdh1 mutations and its PTX-resistant variant and demonstrated the efficacy of DASA in treating PTX-resistant GCPM.

Immune checkpoint inhibitors (ICIs) plus chemotherapy have become a new first-line treatment option for patients with locally advanced or metastatic gastric cancer. However, it is still controversial whether to choose chemotherapy alone or ICIs plus chemotherapy as the first-line treatment option due to a lack of ideal predictive biomarkers for the efficacy. This study intended to explore the predictive value of inflammatory markers for the efficacy of first-line ICIs plus chemotherapy in this disease.

This retrospective study included 131 patients with locally advanced or metastatic gastric cancer who received first-line treatment between July, 2020 and June, 2023. Among them, 76 received first-line ICIs plus chemotherapy and 55 received chemotherapy alone. Firstly, Kaplan-Meier and Cox regression analyses were used to explore the correlation between inflammatory markers and efficacy of first-line ICIs plus chemotherapy. Subsequently, the predictive value of combined baseline and dynamic changes in inflammatory markers was explored. Moreover, the predictive value of baseline inflammatory markers was further verified by comparing efficacy of ICIs plus chemotherapy with that of chemotherapy alone.

In patients receiving first-line ICIs plus chemotherapy, low baseline monocyte-to-lymphocyte ratio (MLR) in peripheral blood was significantly associated with better progression-free survival (PFS) and overall survival (OS), and was an independent prognostic factor for OS. In addition, dynamic early changes of MLR also played predictive role. Patients whose MLR was lower at baseline and after two cycles of treatment had better OS (P = 0.009). Furthermore, compared to chemotherapy alone, patients with a lower baseline MLR were more likely to benefit from first-line ICIs plus chemotherapy.

MLR could serve as a new biomarker to predict the efficacy of first-line ICIs plus chemotherapy in patients with locally advanced or metastatic gastric cancer. And it is helpful to select the candidates for first-line ICIs plus chemotherapy, which is worthy of further study.

More than 90% of advanced gastric cancers (GC) are microsatellite-stable (MSS). Compared to the high response rate of immune checkpoint inhibitors (ICI) in microsatellite-instability-high (MSI-H) GCs, only 10% of unstratified MSS GCs respond to ICIs. In this study, we apply semi-supervised learning to stratify potential ICI responders in MSS GCs, achieving high accuracy, quantified by an area under the curve of 0.924. Spatial analysis of the tumor microenvironment of ICI-sensitive GCs reveals a high level of T-bet+ CD8 + T cell infiltration in their tumor compartments. T-bet+ CD8 + T cells exhibit superior anti-tumor activity due to their increased ability to infiltrate tumors and secrete cytotoxic molecules. Adoptive transfer of T-bet+ CD8 + T cells boosts anti-tumor immunity and confers susceptibility to ICIs in immune-ignorant MSS GCs in a humanized mouse model. Spatial RNA sequencing suggests a positive-feedback loop between T-bet+ T cells and PD-L1+ tumor cells, which eventually drives T cell exhaustion and can therefore be leveraged for ICI therapy. In summary, our research provides insights into the underlying mechanism of anti-tumor immunity and deepens our understanding of varied ICI responses in MSS GCs.

The immune composition of solid tumors is typically inferred from biomarkers, such as histologic and molecular classifications, somatic mutational burden, and PD-L1 expression. However, the extent to which these biomarkers predict the immune landscape in gastric adenocarcinoma-an aggressive cancer often linked to chronic inflammation-remains poorly understood. We leveraged high-dimensional spectral cytometry to generate a comprehensive single-cell immune landscape of tumors, normal tissue, and lymph nodes from patients in the Western Hemisphere with gastric adenocarcinoma. The immune composition of gastric tumors could not be predicted by traditional metrics such as tumor histology, molecular classification, mutational burden, or PD-L1 expression via IHC. Instead, our findings revealed that innate immune surveillance within tumors could be anticipated by the immune profile of the normal gastric mucosa. Additionally, distinct T-cell states in the lymph nodes were linked to the accumulation of activated and memory-like CD8+ tumor-infiltrating lymphocytes. Unbiased reclassification of patients based on tumor-specific immune infiltrate generated four distinct subtypes with varying immune compositions. Tumors with a T cell-dominant immune subtype, which spanned The Cancer Genome Atlas molecular subtypes, were exclusively associated with superior responses to immunotherapy. Parallel analysis of metastatic gastric cancer patients treated with immune checkpoint blockade showed that patients who responded to immunotherapy had a pretreatment tumor composition that corresponded to a T cell-dominant immune subtype from our analysis. Taken together, this work identifies key host-specific factors associated with intratumoral immune composition in gastric cancer and offers an immunological classification system that can effectively identify patients likely to benefit from immune-based therapies.

Combinations of immune checkpoint inhibitors (ICIs) and chemotherapy have become the standard first-line treatment for human epidermal growth factor receptor 2 (HER-2)-negative advanced gastric cancer. However, primary resistance remains a challenge, with no effective biomarkers available for its prediction. This retrospective study explores the relationship between the baseline inflammatory burden index (IBI) and primary resistance in such context.

We analyzed 62 patients with HER-2-negative advanced gastric cancer who received ICIs and chemotherapy as their first-line treatment. The IBI was calculated as follows: C-reactive protein (mg/L) × neutrophil count (10³/mm³)/lymphocyte count (10³/mm³). Based on disease progression within 6 months, patients were categorized into the primary resistant or the control group. We compared baseline characteristics and IBI scores between the groups and assessed the predictive value of the IBI using the receiver operating characteristic curve. Both univariate and multivariate binary logistic regression analyses were conducted to identify factors influencing primary resistance.

Nineteen patients were included in the primary resistance group, and forty-three patients were included in the control group. The IBI was significantly higher in the resistant group compared to the control group (P<0.01). The area under the curve for the IBI was 0.82, indicating a strong predictive value. Multivariate analysis identified the IBI as an independent predictor of primary resistance (P=0.014).

The baseline IBI holds promise as a predictor of primary resistance to combined ICIs and chemotherapy in patients with HER-2-negative advanced gastric cancer.

Combination therapy of chemotherapy and zolbetuximab demonstrated a significant survival benefit compared to chemotherapy alone in patients with human epidermal growth factor receptor 2 (HER2)-negative, claudin (CLDN) 18.2-positive metastatic gastric cancer (mGC). Consequently, it has been approved as a standard first-line therapy for these patients. Combination therapy of chemotherapy and immune checkpoint inhibitors (ICIs)-either nivolumab or pembrolizumab-is a standard first-line therapy for patients with HER2-negative mGCs that are positive for programmed death-ligand 1 (PD-L1) expression, as defined by a combined positive score (CPS). Although approximately 13-22% of CLDN-positive mGCs are also CPS-positive, optimal treatment for mGC patients expressing both CLDN and PD-L1 remains undetermined due to the absence of direct comparative studies between zolbetuximab and ICIs. Treatment selection under this condition has become a critical issue. In this review, we discuss the appropriate treatment selection for HER2-negative mGC patients who are double-positive for CLDN 18.2 and PD-L1 based on clinical data and differences in the mechanism of action and safety profile between zolbetuximab and ICI.

Advances in the identification of molecular biomarkers and the development of targeted therapies have enhanced the prognosis of patients with advanced gastric cancer. Several established biomarkers have been widely integrated into routine clinical diagnostics of gastric cancer to guide personalized treatment. Human epidermal growth factor receptor 2 (HER2) was the first molecular biomarker to be used in gastric cancer with trastuzumab being the first approved targeted therapy for HER2-positive gastric cancer. Programmed death-ligand 1 positivity and microsatellite instability can guide the use of immunotherapies, such as pembrolizumab and nivolumab. More recently, zolbetuximab has been approved for patients with claudin 18.2-positive diseases in some countries. More targeted therapies, including savolitinib for MET-positive patients, are currently under clinical investigation. However, the clinical application of these diagnostic approaches could be hampered by many existing challenges, including invasive and costly sampling methods, variability in immunohistochemistry interpretation, high costs and long turnaround times for next-generation sequencing, the absence of standardized and clinically validated diagnostic cut-off values for some biomarkers, and tumor heterogeneity. Novel testing and analysis techniques, such as artificial intelligence-assisted image analysis and multiplex immunohistochemistry, and emerging therapeutic strategies, including combination therapies that integrate immune checkpoint inhibitors with targeted therapies, offer potential solutions to some of these challenges. This article reviews recent progress in gastric cancer testing, outlines current challenges, and explores future directions for biomarker testing and targeted therapy for gastric cancer.

Ramucirumab with either solvent-based or nanoparticle albumin-bound paclitaxel is a standard second-line treatment for advanced gastric cancer. Reportedly, nanoparticle albumin-bound paclitaxel has activated the immune system, but the efficacy of taxane-based agents before nivolumab remains unclear. Therefore, we investigated the prognostic effect of ramucirumab with solvent-based or nanoparticle albumin-bound paclitaxel as second-line therapy, followed by nivolumab as third-line therapy.

This retrospective study enrolled 115 patients with gastric cancer treated with ramucirumab in combination with solvent-based paclitaxel or nanoparticle albumin-bound paclitaxel from 2017 to 2019 at six hospitals. All patients received nivolumab as a third-line therapy. Ramucirumab + solvent-based paclitaxel and ramucirumab + nanoparticle albumin-bound paclitaxel were administered to 57 and 58 patients, respectively.

The progression-free survival of the ramucirumab + solvent-based paclitaxel group was slightly better than that of the ramucirumab + nanoparticle albumin-bound paclitaxel group but with no statistically significant difference (5.3 months vs. 4.2 months). Contrary, the overall survival of the ramucirumab + nanoparticle albumin-bound paclitaxel group was slightly better than the ramucirumab + solvent-based paclitaxel group but with no statistically significant difference (19.0 months vs. 12.5 months). The multivariate analysis of progression-free survival revealed that ramucirumab + nanoparticle albumin-bound paclitaxel was an independent risk factor for poor prognosis, whereas ramucirumab + nanoparticle albumin-bound paclitaxel was an independent factor for good overall survival.

Ramucirumab + nanoparticle albumin-bound paclitaxel may prolong overall survival when administered before nivolumab, despite its limited effect on progression-free survival.

HER2-positive advanced esophageal adenocarcinoma (EAC) cases demonstrate a poor prognosis because of drug resistance that develops after standard first-line trastuzumab therapy. The patient was initially diagnosed with stage cT2N1M0 III EAC. He underwent neoadjuvant chemotherapy, radical esophageal resection, and postoperative adjuvant radiotherapy. However, four months after treatment, the lesion relapsed and progressed to the right back, rendering the case inoperable. Pathological analysis revealed HER2 amplification. Given a poor tolerance to chemotherapy, the patient was administered cadonilimab and trastuzumab for three months. Subsequently, the second-line therapy was switched to pyrotinib monotherapy as a salvage treatment. Remarkably, after one month of treatment, the tumor showed significant reduction, with mild toxic side effects. Pyrotinib can be used for salvage later-line therapy in HER2-positive advanced EAC with trastuzumab resistance or poor chemotherapy tolerance, which deserves further promotion.

Treatment with cadonilimab and chemotherapy has shown promise as a first-line treatment for gastric or gastroesophageal junction (G/GEJ) adenocarcinoma. However, its application in neoadjuvant settings has not yet been documented.

This multicenter, phase 2 trial (ChiCTR2200066893) was conducted at four hospitals across China. Treatment-naive patients with locally advanced G/GEJ adenocarcinoma (cT3/4, N+, M0) and who were human epidermal growth factor receptor 2 negative received 3-cycle or 4-cycle neoadjuvant treatment of cadonilimab plus FLOT (5-fluorouracil, leucovorin, oxaliplatin, and docetaxel) chemotherapy, followed by gastrectomy and 4-cycle adjuvant FLOT chemotherapy. The primary endpoint was the pathological complete response (pCR) rate. Secondary endpoints included major pathological response (MPR), overall response rate (ORR), disease control rate (DCR), R0 resection rate, downstaging rate, and safety.

Between December 23, 2022, and December 15, 2023, 32 of 38 patients completed the scheduled treatment, achieving an R0 resection rate of 100% (32/32). The pCR rate was 21.1% (8/38, 90% confidence interval [CI]: 9.7-32.4), and the MPR rate was 44.7% (17/38, 90% CI: 30.9-58.5). Radiological evaluations were available for 28 of 38 patients by blinded independent central review. The ORR was 60.7% (17/28, 90% CI: 44.7-76.7), and the DCR was 100.0% (28/28, 90% CI: 100.0-100.0). Tumor downstaging occurred in 71.9% of patients (23/32), with consistent efficacy across all populations observed in the subgroup analysis. Grade 3 adverse events occurred in 31.6% of patients without severe safety issues.

Neoadjuvant cadonilimab plus FLOT chemotherapy treatment exhibits promising efficacy with manageable toxicities in locally advanced G/GEJ adenocarcinoma, providing preliminary evidence for further investigation.

This study was funded by Akeso Biopharma.

Pembrolizumab, a PD-1 inhibitor, has shown potential for treating advanced gastric and gastroesophageal junction (GEJ) cancer. This meta-analysis evaluates its efficacy and safety, alone or combined with chemotherapy, in this population.

A systematic review and meta-analysis were conducted in accordance with PRISMA guidelines. Databases including PubMed, Embase, the Cochrane Central Register of Controlled Trials, and Web of Science were searched up to October 31, 2024. Twelve studies comprising 4,069 patients were included. The primary outcomes were overall survival (OS) and progression-free survival (PFS); secondary outcomes included objective response rate (ORR), adverse events (AEs), and grade ≥ 3 AEs. Effect sizes were calculated using mean differences (MDs) and odds ratios (ORs) with 95% confidence intervals (CIs).

Pembrolizumab combined with chemotherapy significantly improved OS (MD = 1.92 months; 95% CI: 0.94 to 2.91) and ORR (MD = 11.05%; 95% CI: 6.29 to 15.82) compared to chemotherapy alone. Pembrolizumab monotherapy did not show a significant effect on OS (MD = 0.24 months; 95% CI: -1.15 to 1.63) and was associated with a significant reduction in PFS (MD = -2.28 months; 95% CI: -2.85 to -1.71) compared to chemotherapy alone. For safety, pembrolizumab monotherapy significantly reduced the risk of AEs (OR = 0.68; 95% CI: 0.57 to 0.81) and grade ≥ 3 AEs (OR = 0.39; 95% CI: 0.30 to 0.51) compared to chemotherapy. Pembrolizumab combined with chemotherapy did not significantly alter the risk of AEs (OR = 1.01; 95% CI: 0.90 to 1.13) or grade ≥ 3 AEs (OR = 1.12; 95% CI: 0.99 to 1.27) compared to chemotherapy alone.

Pembrolizumab combined with chemotherapy improves survival and response rates with a manageable safety profile in advanced gastric and GEJ cancers. Monotherapy shows limited efficacy, highlighting the need for combination strategies and patient selection.

Patients with clinical T2N0 (cT2N0) gastric adenocarcinoma are recommended to undergo either perioperative chemotherapy or upfront resection. If T2N0 disease is pathologically confirmed, patients may be observed without chemotherapy. These guidelines create the possibility of both systemic therapy overuse and underuse depending on clinical staging accuracy. Our objectives were to define factors associated with upstaging after upfront resection and describe the association between postoperative chemotherapy and survival.

Patients with cT2N0 gastric adenocarcinoma were identified using the National Cancer Database. Factors associated with upstaging were assessed by logistic regression. Survival was assessed using Kaplan-Meier and Cox proportional hazard analyses.

Of 4,076 patients undergoing upfront resection for cT2N0 gastric cancer, 1,933 (47.4%) were pathologically upstaged. Patients were more likely to be upstaged if they had >3.0-cm (adjusted odds ratio [aOR] 2.31, 95% confidence interval [CI] 1.97-2.70; P < .001) or poorly differentiated tumors (aOR 2.22, 95% CI 1.89-2.60; P < .001). Patients were less likely to be upstaged if they had distal tumors (aOR 0.77, 95% CI 0.64-0.93; P = .006). Of those pathologically upstaged (n = 1,933), 1,111 (57.4%) received adjuvant chemotherapy that was associated with improved survival (HR 0.55, 95% CI 0.47-0.63; P < .001). Among those not upstaged (n = 2,143), 247 (11.5%) received adjuvant chemotherapy that was not associated with improved survival (HR 0.92, 95% CI 0.70-1.21; P = .54).

Pathologic upstaging after upfront resection in patients with cT2N0 gastric cancer is associated with patient and tumor characteristics. Adjuvant chemotherapy is associated with improved survival only in the patients upstaged at surgery. An upfront surgical approach may be preferred in select patients, especially if avoiding chemotherapy is desired.

In less than a decade, immune checkpoint inhibitors (ICIs) have transformed the management of mismatch repair-deficient (dMMR) and microsatellite instability-high (MSI) cancers. However, beyond colorectal cancer (CRC), much of the evidence is mostly derived from non-randomized phase II studies or post-hoc analyses of broader clinical trials. dMMR/MSI tumours represent a specific subgroup of gastro-esophageal adenocarcinomas (GEA), accounting for approximately 9 % of cases, with a higher prevalence in early-stage compared to advanced-stage disease and older female patients. These tumours are predominantly sporadic, often linked to MLH1 promoter methylation, and rarely exhibit HER2 overexpression/ERBB2 amplification or other oncogenic drivers. The treatment landscape for early stage dMMR/MSI GEA is likely to change substantially soon, as ICIs have shown high pathological complete response (pCR) rates in small phase II trials, raising questions on optimisation of neoadjuvant therapy, and paving the way for organ preservation. The standard of treatment for untreated patients with advanced dMMR/MSI GEA is chemotherapy + ICI irrespectively of PDL-1 status. However, the role of chemotherapy-free regimen consisting of CTLA-4 plus PD-1 inhibitors remains undetermined. This review addresses these and other emerging questions, offering expert opinions and insights into the future therapeutic landscape for dMMR/MSI GEA.

Microsatellite instability (MSI)-high tumors represent a distinct, small-fraction subtype in esophagogastric junction cancer or gastric cancer (GC), yet their clinical significance remains poorly understood. This study aimed to investigate the prevalence and clinicopathological features of chemotherapy-naïve metastatic or recurrent MSI-high GC as a prescreening study for a phase II trial of nivolumab plus ipilimumab.

Key inclusion criteria included metastatic or recurrent adenocarcinoma of GC, ECOG performance status of 0 or 1, and no prior systemic therapy for metastatic or recurrent disease. MSI status was tested using multiplex PCR fragment analysis (MSI Testing Kit, FALCO). The primary endpoint was the prevalence of MSI-high GC.

Between October 2020 and October 2022, 930 eligible patients from 75 centers in Japan were analyzed. The prevalence of MSI-high GC was 5.6% (95% CI 4.2-7.3). MSI-high GC was more frequently observed in females than males (9.6% vs 3.8%, p < 0.001), patients aged ≥ 70 years compared to those < 70 years (8.0% vs 2.8%, p < 0.001), in the lower stomach than other locations (10.5% vs 3.2%, p < 0.001), HER2-negative tumors than HER2-positive tumors (6.5% vs 1.8%, p = 0.02), and in patients without liver metastasis than those with liver metastasis (6.9% vs 2.2%, p = 0.004).

The prevalence of MSI-high tumors among chemotherapy-naïve patients with unresectable GC was 5.6%. These tumors were associated with female sex, older age, lower stomach, HER2-negative, and absence of liver metastasis. These findings would help assuming MSI-high tumors and may have significant implications for clinical practice and studies targeting this GC subtype.

In resectable gastric/gastroesophageal junction adenocarcinoma, microsatellite instability-high (MSI-H) confers improved survival, but limited benefit from chemotherapy. Immunotherapy may eliminate the need for chemotherapy or surgery.

INFINITY is a multicenter, multicohort phase II trial (NCT04817826) investigating in cohort 1 the activity and safety of tremelimumab + durvalumab (T300/D) as neoadjuvant treatment of mismatch repair deficient/MSI-H, resectable gastric/gastroesophageal junction adenocarcinoma. Primary endpoint was pathologic complete response (pCR) rate; Secondary endpoints: progression-free survival (PFS), overall survival (OS), quality of life, and translational analyses. In cohort 2, the activity and safety of T300/D was explored as definitive treatment in patients achieving clinical complete response (cCR). Primary endpoint was 2-year cCR rate, and secondary endpoints were PFS, OS, quality of life, gastrectomy-free survival and translational analyses.

In cohort 1, 18 patients were recruited and 15 evaluable. pCR and major pathologic response-pCR were 60% and 80%, respectively. Since pCR rate in T4 tumors was 17%, this subgroup of patients was excluded from enrollment in cohort 2. At 28.1 months median follow-up, 24-month gastric cancer-specific PFS and OS rates were 85% and 92%, respectively. In cohort 2, 18 patients were enrolled and 17 assessable, and 13 had cCR and started non-operative management. At 11.5 months median follow-up, one patient had local regrowth and underwent salvage surgery; 12-month gastrectomy-free survival was 64.2%.

The INFINITY study provided promising activity results of a chemo-free T300/D combination regimen as preoperative treatment in mismatch repair deficient/MSI gastric/gastroesophageal junction adenocarcinoma and the first available feasibility results of a non-operative management strategy in this disease setting, worthy of further validation in larger cohorts.

Gastric adenocarcinoma is a highly lethal neoplasm with a short survival especially when metastatic. Few effective treatments are available for the control of the disease and palliation of patients with metastatic gastric cancer. Although progress has been made in the elucidation of molecular pathways invoked in gastric carcinogenesis, this knowledge has not yet led to major breakthroughs, in contrast to several other types of cancer. The role of stem cell transcription factors SOX2 and CDX2 is of particular interest in the pathogenesis of gastric cancer.

The cohort of gastric adenocarcinomas from The Cancer Genome Atlas (TCGA) was interrogated and two groups of gastric cancers, with CDX2 induction and SOX2 suppression on the one hand and with CDX2 induction and SOX2 maintained expression on the other hand were retained. The induction of expression of the two transcription factors was defined as a mRNA expression z score compared with normal samples above zero. The two groups were compared for clinical-pathologic and genomic differences.

Among gastric cancers with up-regulated CDX2 mRNA, cancers with suppressed SOX2 mRNA were slightly more numerous (55.9%) than those with a maintained SOX2 expression. The SOX2 suppressed group had a higher prevalence of MSI high cancers (30.9% versus 10%) and of cases with high tumor mutation burden (35% versus 12.4%) than cancers with a SOX2 maintained expression, which presented more frequently high Chromosomal Instability (CIN). The group with SOX2 suppression had higher rates of mutations in many gastric cancer-associated genes such as epigenetic modifiers ARID1A, KMT2D, KMT2C, and KMT2B, as well as higher rates of mutations in genes encoding for receptor tyrosine kinases ERBB4 and FGFR1. On the other hand, TP53 mutations and amplifications in MYC, ERBB2, and CCNE1 were more common in the group with a maintained expression of SOX2, approaching significance for MYC.

Notable differences are present in the genomic landscape of CDX2-induced gastric cancer depending on the level of expression of SOX2 mRNA. Despite this, SOX2 mRNA expression levels were not prognostic.

Although the emergence of immunotherapy has benefited patients with advanced gastric cancer (AGC), the magnitude of the benefit among real-world patients with HER2-negative AGC remains unclear.

The current study aimed to evaluate the treatment features across various immunotherapy approval periods and investigate the utility of immunotherapy for patients with HER2-negative AGC in daily practice.

Retrospective observational study.

We retrospectively evaluated the clinical outcomes of patients with HER2-negative AGC who received first-line platinum-based chemotherapy between 2011 and 2023 across different periods of immunotherapy approval in Japan: Group A (pre-immunotherapy approval): 2011-2017; Group B (approved for third-line treatment or later): 2018-2021; and Group C (approved for first-line treatment): 2022-2023.

A total of 949 patients were enrolled (n = 477, 344, and 128 for Groups A, B, and C, respectively). Patient characteristics were comparable between the three groups, except for the proportion of those aged ⩾75 years (p = 0.002), prior gastrectomy (p = 0.03), and liver metastases (p = 0.0005). The median overall survival (OS) was 16.2, 15.2, and 21.3 months in Groups A, B, and C, respectively, with no significant difference between the groups (log-rank p = 0.50). Patients who received first-line immunotherapy plus chemotherapy (n = 173) showed significantly better OS than did those who did not receive any immunotherapy-containing treatment from 2011 to 2017 (n = 382; hazard ratio (HR), 0.78; 95% confidence interval (CI), 0.61-0.99; p = 0.04). Multivariate analysis showed that the use of first-line immunotherapy was not significantly associated with worse OS, whereas the use of any-line immunotherapy was significantly associated with prognosis (HR, 0.54; 95% CI, 0.47-0.63; p < 0.0001). The proportion of patients receiving any second-line treatment was comparable between the groups: 76%, 80%, and 71%, respectively.

Our study suggests that immunotherapy has a moderate impact on improving the survival of real-world patients with HER2-negative AGC, highlighting the need for appropriate treatment strategies, including efforts to identify biomarkers and the development of other agents.

Microsatellite instability-high (MSI-H) gastric cancer (GC) is recognized as a unique subtype of gastric cancer. While patients with advanced MSI-H gastric cancer may respond favorably to a combination of immune checkpoint inhibitors and chemotherapy in first-line treatment, no definitive recommendations exist regarding the optimal regimen for subsequent therapy. Cadonilimab, a PD-1 and CTLA-4 bispecific antibody, has shown encouraging efficacy and safety in the first-line treatment of advanced gastric cancer. However, its utility in the MSI-H gastric cancer subtype following multiple lines of therapy remains uncertain. This case report describes a patient with advanced MSI-H gastric adenocarcinoma that progressed after multiple treatments and achieved notable efficacy with a combination of cadonilimab and apatinib. By examining the current therapeutic landscape for MSI-H gastric cancer, this study explores the potential of combining PD-1/CTLA-4 dual-immunity with anti-vascular therapy as salvage treatment for this gastric cancer subtype. The findings provide valuable reference points for future clinical trials, offering a promising perspective on backline therapeutic strategies for MSI-H gastric cancer and highlighting the potential of integrating bispecific antibodies with anti-vascular therapies.

Objective: To compare the efficacy and safety of immunotherapy combined with chemotherapy as the first-line treatment for advanced gastric cancer. Data Sources: Phase III randomised controlled trials were searched from PubMed, Embase, Web of Science, Cochrane Library, and ClinicalTrials databases, and several international conference databases, from inception to 15 November 2024. Results: A total of eight eligible trials involved 7898 patients and eight treatments. The network meta-analysis showed that cadonilimab plus chemotherapy was the most superior treatment in improving overall survival (versus conventional chemotherapy, hazard ratio 0.62, 95% credible interval 0.50 to 0.78) and progression-free survival (0.53, 0.43 to 0.65), and consistency of results were observed in specific PD-L1 combined positive score groups. All immune checkpoint inhibitors combined with chemotherapy improved patient prognosis, but nivolumab plus chemotherapy may lead to an increase in grade 3 or higher adverse events (odds ratio 1.68, 95% credible interval 1.04 to 2.54), and the toxicity of cadonilimab plus chemotherapy was more likely to force patients to discontinue treatment. Conclusions: These results showed that cadonilimab plus chemotherapy had the best overall survival and progression-free survival benefits for advanced gastric cancer patients with HER-2 negative, and was preferentially recommended to patients with positive PD-L1 CPS.

Gastric cancer (GC) is one of the most common malignant tumors worldwide, and its treatment has been a focus of medical research. Herein we systematically review the current status of and advancements in targeted therapy and immunotherapy for GC, which have emerged as important treatment strategies in recent years with great potential, and summarize the efficacy and safety of such treatments. Targeted therapies against key targets in GC, including epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), and vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR), have shown remarkable therapeutic efficacies by inhibiting tumor progression and/or blood supply. In particular, markable breakthroughs have been made in HER2-targeting drugs for HER2-positive GC patients. To address intrinsic and acquired resistances to HER2-targeting drugs, novel therapeutic agents including bispecific antibodies and antibody-drug conjugates (ADC) targeting HER2 have been developed. Immunotherapy enhances the recognition and elimination of cancer cells by activating body anticancer immune system. Programmed cell death protein 1 (PD-1) and programmed cell death-ligand 1 (PD-L1) antibodies are the most commonly used immunotherapeutic agents and have been used with some success in GC treatment. Innovative immunotherapy modalities, including adoptive immune cell therapy, tumor vaccines, and non-specific immunomodulators therapy, and oncolytic viruses have shown promise in early-stage clinical trials for GC. Clinical trials have supported that targeted therapy and immunotherapy can significantly improve the survival and quality of life of GC patients. However, the effects of such therapies need to be further improved and more personalized, with advancement in researches on tumor immune microenvironment. Further studies remain needed to address the issues of drug resistance and adverse events pertaining to such therapies for GC. The combined application of such therapies and individualized treatment strategies should be further explored with novel drugs developed, to provide more effective treatments for GC patients.

This review addresses the current treatment paradigm and new advancements in the management of microsatellite instability-high/mismatch repair deficient (MSI-H/dMMR) esophagogastric cancer (EGC).

While chemotherapy and surgery remain the cornerstone of EGC treatment, MSI-H/dMMR tumors harbor high tumor mutational burden and represent a subset of patients who benefit from immune checkpoint inhibitors (ICI). ICI has been incorporated in the front line setting with and without chemotherapy for advanced disease. Recently, ICI has been studied in the perioperative setting for resectable disease. Though perioperative ICI results in improved response rates, it is not yet clear whether this translates to a survival benefit. Despite high response rates with ICI in this patient population, many do not respond to therapy, representing a major challenge in treatment. Preclinical studies have highlighted potential mechanisms of resistance which will guide drug development and clinical trials.