Clinicopathologic factors associated with HER2-positive gastric cancer and its impact on survival outcomes--a systematic review

HER2 testing: evolution and update for a companion diagnostic assay

Human epidermal growth factor receptor 2 (HER2; encoded by ERBB2) testing has been a cornerstone of patient selection for HER2-targeted therapies, principally in breast cancer but also in several other solid tumours. Since the introduction of HercepTest as the original companion diagnostic for trastuzumab, HER2 assessment methods have evolved substantially, incorporating various testing modalities, from western blots, immunohistochemistry and fluorescence in situ hybridization, to early chromogenic quantitative methods and, probably in the future, fully quantitative methods. The advent of highly effective HER2-targeted antibody-drug conjugates with clinical activity at low levels of HER2 expression, such as trastuzumab deruxtecan, has necessitated the re-evaluation of HER2 testing, particularly for HER2-low tumours. In this Review, we provide an in-depth overview of the evolution of HER2 testing, the current clinical guidelines for HER2 testing across various solid tumours, challenges associated with current testing methodologies and the emerging potential of quantitative techniques. We discuss the importance of accurately defining HER2-low expression for therapeutic decision-making and how newer diagnostic approaches, such as quantitative immunofluorescence and RNA-based assays, might address the limitations of traditional immunohistochemistry-based methods. As the use of HER2-targeted therapies continues to expand to a wider range of tumour types, ensuring the precision and accuracy of HER2 testing will be crucial for guiding treatment strategies and improving patient outcomes.

Tucatinib in the treatment of HER2-overexpressing gastrointestinal cancers: current insights and future prospects

INTRODUCTION

Over the past 20 years, the treatment landscape of HER2-amplified tumors has considerably evolved. Until now, no approved targeted therapies were available for patients with HER2-amplified metastatic colorectal cancer (mCRC). Tucatinib, a highly selective tyrosine kinase inhibitor, demonstrated significant efficacy in combination with trastuzumab in patients with refractory mCRC, leading to its approval by the Food and Drug Administration (FDA).

AREAS COVERED

This review dives into the efficacy of tucatinib-based regimens in gastrointestinal malignancies, with a focus on the pivotal MOUNTAINEER trial, which led to the FDA approval of tucatinib plus trastuzumab in chemo-refractory HER2-amplified mCRC. Additionally, ongoing trials are exploring tucatinib in earlier treatment lines and across other gastrointestinal cancers, including biliary tract, gastric, and pancreatic malignancies. The mechanistic basis of dual HER2 inhibition and its implications for clinical practice are discussed.

EXPERT COMMENTARY

The future of tucatinib-based therapeutic strategies in GI malignancies depends on their integration into different treatment lines. Addressing acquired resistance using liquid biopsy-guided strategies and other TKIs like lapatinib will be paramount to improve outcomes.

Non-Coding RNAs in Breast Cancer: Diagnostic and Therapeutic Implications

Breast cancer (BC) is one of the most prevalent forms of cancer globally, and has recently become the leading cause of cancer-related mortality in women. BC is a heterogeneous disease comprising various histopathological and molecular subtypes with differing levels of malignancy, and each patient has an individual prognosis. Etiology and pathogenesis are complex and involve a considerable number of genetic alterations and dozens of alterations in non-coding RNA expression. Non-coding RNAs are part of an abundant family of single-stranded RNA molecules acting as key regulators in DNA replication, mRNA processing and translation, cell differentiation, growth, and overall genomic stability. In the context of breast cancer, non-coding RNAs are involved in cell cycle control and tumor cell migration and invasion, as well as treatment resistance. Alterations in non-coding RNA expression may contribute to the development and progression of breast cancer, making them promising biomarkers and targets for novel therapeutic approaches. Currently, the use of non-coding RNAs has not yet been applied to routine practice; however, their potential has been very well studied. The present review is a literature overview of current knowledge and its objective is to delineate the function of diverse classes of non-coding RNAs in breast cancer, with a particular emphasis on their potential utility as diagnostic and prognostic markers or as therapeutic targets and tools.

Hyperthermic intraoperative peritoneal chemotherapy and cytoreductive surgery for people with peritoneal metastases: a systematic review and cost-effectiveness analysis

Background

We compared the relative benefits, harms and cost-effectiveness of hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery ± systemic chemotherapy versus cytoreductive surgery ± systemic chemotherapy or systemic chemotherapy alone in people with peritoneal metastases from colorectal, gastric or ovarian cancers by a systematic review, meta-analysis and model-based cost-utility analysis.

Methods

We searched MEDLINE, EMBASE, Cochrane Library and the Science Citation Index, ClinicalTrials.gov and WHO ICTRP trial registers until 14 April 2022. We included only randomised controlled trials addressing the research objectives. We used the Cochrane risk of bias tool version 2 to assess the risk of bias in randomised controlled trials. We used the random-effects model for data synthesis when applicable. For the cost-effectiveness analysis, we performed a model-based cost-utility analysis using methods recommended by The National Institute for Health and Care Excellence.

Results

The systematic review included a total of eight randomised controlled trials (seven randomised controlled trials, 955 participants included in the quantitative analysis). All comparisons other than those for stage III or greater epithelial ovarian cancer contained only one trial, indicating the paucity of randomised controlled trials that provided data. For colorectal cancer, hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy probably results in little to no difference in all-cause mortality (60.6% vs. 60.6%; hazard ratio 1.00, 95% confidence interval 0.63 to 1.58) and may increase the serious adverse event proportions compared to cytoreductive surgery ± systemic chemotherapy (25.6% vs. 15.2%; risk ratio 1.69, 95% confidence interval 1.03 to 2.77). Hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy probably decreases all-cause mortality compared to fluorouracil-based systemic chemotherapy alone (40.8% vs. 60.8%; hazard ratio 0.55, 95% confidence interval 0.32 to 0.95). For gastric cancer, there is high uncertainty about the effects of hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy versus cytoreductive surgery + systemic chemotherapy or systemic chemotherapy alone on all-cause mortality. For stage III or greater epithelial ovarian cancer undergoing interval cytoreductive surgery, hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy probably decreases all-cause mortality compared to cytoreductive surgery + systemic chemotherapy (46.3% vs. 57.4%; hazard ratio 0.73, 95% confidence interval 0.57 to 0.93). Hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy may not be cost-effective versus cytoreductive surgery + systemic chemotherapy for colorectal cancer but may be cost-effective for the remaining comparisons.

Limitations

We were unable to obtain individual participant data as planned. The limited number of randomised controlled trials for each comparison and the paucity of data on health-related quality of life mean that the recommendations may change as new evidence (from trials with a low risk of bias) emerges.

Conclusions

In people with peritoneal metastases from colorectal cancer with limited peritoneal metastases and who are likely to withstand major surgery, hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy should not be used in routine clinical practice (strong recommendation). There is considerable uncertainty as to whether hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy or cytoreductive surgery + systemic chemotherapy should be offered to patients with gastric cancer and peritoneal metastases (no recommendation). Hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy should be offered routinely to women with stage III or greater epithelial ovarian cancer and metastases confined to the abdomen requiring and likely to withstand interval cytoreductive surgery after chemotherapy (strong recommendation).

Future work

More randomised controlled trials are necessary.

Study registration

This study is registered as PROSPERO CRD42019130504.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 17/135/02) and is published in full in Health Technology Assessment; Vol. 28, No. 51. See the NIHR Funding and Awards website for further award information.

Pembrolizumab in combination with trastuzumab for treatment of HER2-positive advanced gastric or gastro-esophageal junction cancer

Introduction

Gastric cancer remains a challenging malignancy with a high global mortality rate. Recent advances in targeted therapy and immunotherapy have shown promise in improving patient outcomes. This paper reviews the impact of incorporating targeted agents such as trastuzumab and immunotherapeutic agents like pembrolizumab into standard chemotherapy regimens for gastric cancer treatment.

Methods

A comprehensive analysis was conducted on pivotal clinical trials, including KEYNOTE-590, KEYNOTE-811, and ToGA, focusing on their methodologies, patient populations, treatment regimens, and outcome measures. The review also explored emerging research avenues in precision medicine, particularly genomic sequencing and biomarker identification.

Aim

To assess the efficacy and survival benefits of adding trastuzumab and pembrolizumab to standard chemotherapy in the treatment of gastric cancer and to outline future directions in gastric cancer research.

Results

Including trastuzumab and pembrolizumab in treatment regimens for human epidermal growth factor receptor 2 (HER2)-positive and PD-L1-expressing gastric cancers significantly improved progression-free and overall survival rates compared to chemotherapy alone. These findings highlight the potential of personalized therapy in enhancing treatment outcomes. Furthermore, ongoing research into the gastric cancer microenvironment and the role of the microbiome suggests novel targets for future therapeutic interventions.

Conclusion

The integration of targeted and immunotherapeutic agents with traditional chemotherapy represents a pivotal shift in gastric cancer treatment, moving towards more personalized and effective regimens.

Effect of HER2/CEP17 ratio on survival in metastatic HER2-positive gastric cancer, multicenter study

AIM

HER2-positive metastatic gastric cancer is still a highly fatal disease despite advances. We aimed to investigate the relationship between HER2/CEP17 ratio and survival in patients with HER2-positive metastatic gastric cancer.

METHODS

A total of 99 patients from 8 different centers in Turkey were included in the study. Patients with HER2-positive metastatic gastric cancer and whose HER2/CEP17 ratio was examined were included in the study. Patients were divided into two groups according to HER2/CEP17 values, and survival analysis was performed.

RESULTS

The median age was 64 (24-83) years. There were 74 (74.8%) male and 25 (25.2%) female patients. OS in the high HER2/CEP17 ratio group was 21.97 months (95% CI: 16.36-27.58), and in the low ratio group was 16.17 months (95% CI: 10.95-21.38) (p = 0.015). OS was 17.7 months (95% CI: 7.02-28.37) in the high HER2 gene copy number group and 10.13 months (5.55-14.71) in the group with low copy number (p = 0.03). PFS was 10.94 months (95% CI: 7.55-14.33) in the group with high HER2 gene copy number and 7.56 months (4.62-10.49) in the low copy number group (p = 0.06).

CONCLUSION

Patients with both high HER2 gene amplification and high HER2/CEP17 ratio had better OS. The PFS of the group with high HER2 gene amplification was also better. To our knowledge, this is the first study in the literature showing that the HER2/CEP17 ratio affects survival in patients with metastatic gastric cancer.

State of the art and upcoming trends in HER2-directed therapies in gastrointestinal malignancies

PURPOSE OF REVIEW

This review critically evaluates the evolution and current status of human epidermal growth factor receptor 2 (HER2)-directed therapies in upper gastrointestinal (GI) malignancies, a timely and relevant inquiry given the dynamic shifts in therapeutic strategies over the past decade. Initial enthusiasm following the Trastuzumab for Gastric Cancer (ToGA) study's demonstration of trastuzumab's efficacy, however, encountered hurdles due to subsequent trials showing limited progress, underscoring the necessity for a reevaluation of therapeutic approaches and the exploration of novel agents.

RECENT FINDINGS

The review highlights significant breakthroughs in the form of immune checkpoint inhibitors and innovative therapeutic technologies, which have redefined treatment paradigms and shown promising efficacy in HER2-positive cases. Emerging treatments such as trastuzumab deruxtecan (T-DXd), zanidatamab and evorpacept further illustrate the ongoing efforts to leverage unique mechanisms of action for improved HER2-positive antitumor activity.

SUMMARY

The advancements in HER2-directed therapies underscore a pivotal era in the management of upper GI malignancies. These developments not only reflect the profound impact of integrating novel therapeutic combinations but also highlight the critical role of ongoing research in overcoming resistance mechanisms and tailoring treatment to individual disease profiles.

Advances in the Imaging of Esophageal and Gastroesophageal Junction Malignancies

Accurate imaging is key for the diagnosis and treatment of esophageal and gastroesophageal junction cancers . Current imaging modalities, such as computed tomography (CT) and 18F-FDG (2-deoxy-2-[18F]fluoro-D-glucose) positron emission tomography (PET)/CT, have limitations in accurately staging these cancers. MRI shows promise for T staging and residual disease assessment. Novel PET tracers, like FAPI, FLT, and hypoxia markers, offer potential improvements in diagnostic accuracy. 18F-FDG PET/MRI combines metabolic and anatomic information, enhancing disease evaluation. Radiomics and artificial intelligence hold promise for early detection, treatment planning, and response assessment. Theranostic nanoparticles and personalized medicine approaches offer new avenues for cancer therapy.

Advances in Human Epidermal Growth Factor Receptor 2-Targeted Therapy in Upper Gastrointestinal Cancers

The Trastuzumab for Gastric Cancer (ToGA) trial marked a pivotal moment in the adoption of trastuzumab for treating advanced human epidermal growth factor receptor 2 (HER2)-positive esophagogastric (EG) cancer. The KEYNOTE-811 trial brought to light the synergistic effect of immune modulation and HER2 targeting. Additionally, the emergence of trastuzumab deruxtecan (T-DXd) highlighted the potential of new pharmaceutical technologies to extend response, particularly for patients who have advanced beyond initial HER2-targeted therapies. This review aims to navigate through both the successes and challenges encountered historically, as well as promising current trials on innovative and transformative therapeutic strategies, including promising first-in-class and novel first-in-human agents.

AXL - a new player in resistance to HER2 blockade

HER2 is a driver in solid tumors, mainly breast, oesophageal and gastric cancer, through activation of oncogenic signaling pathways such as PI3K or MAPK. HER2 overexpression associates with aggressive disease and poor prognosis. Despite targeted anti-HER2 therapy has improved outcomes and is the current standard of care, resistance emerge in some patients, requiring additional therapeutic strategies. Several mechanisms, including the upregulation of receptors tyrosine kinases such as AXL, are involved in resistance. AXL signaling leads to cancer cell proliferation, survival, migration, invasion and angiogenesis and correlates with poor prognosis. In addition, AXL overexpression accompanied by a mesenchymal phenotype result in resistance to chemotherapy and targeted therapies. Preclinical studies show that AXL drives anti-HER2 resistance and metastasis through dimerization with HER2 and activation of downstream pathways in breast cancer. Moreover, AXL inhibition restores response to HER2 blockade in vitro and in vivo. Limited data in gastric and oesophageal cancer also support these evidences. Furthermore, AXL shows a strong value as a prognostic and predictive biomarker in HER2+ breast cancer patients, adding a remarkable translational relevance. Therefore, current studies enforce the potential of co-targeting AXL and HER2 to overcome resistance and supports the use of AXL inhibitors in the clinic.

A Clinical Viewpoint on the Use of Targeted Therapy in Advanced Gastric Cancer

The development of therapies for advanced gastric cancer (GC) has made significant progress over the past few years. The identification of new molecules and molecular targets is expanding our understanding of the disease's intricate nature. The end of the classical oncology era, which relied on well-studied chemotherapeutic agents, is giving rise to novel and unexplored challenges, which will cause a significant transformation of the current oncological knowledge in the next few years. The integration of established clinically effective regimens in additional studies will be crucial in managing these innovative aspects of GC. This study aims to present an in-depth and comprehensive review of the clinical advancements in targeted therapy and immunotherapy for advanced GC.

Anti-Cancer Potential of Transiently Transfected HER2-Specific Human Mixed CAR-T and NK Cell Populations in Experimental Models: Initial Studies on Fucosylated Chondroitin Sulfate Usage for Safer Treatment

Human epidermal growth factor receptor 2 (HER2) is overexpressed in numerous cancer cell types. Therapeutic antibodies and chimeric antigen receptors (CARs) against HER2 were developed to treat human tumors. The major limitation of anti-HER2 CAR-T lymphocyte therapy is attributable to the low HER2 expression in a wide range of normal tissues. Thus, side effects are caused by CAR lymphocyte "on-target off-tumor" reactions. We aimed to develop safer HER2-targeting CAR-based therapy. CAR constructs against HER2 tumor-associated antigen (TAA) for transient expression were delivered into target T and natural killer (NK) cells by an effective and safe non-viral transfection method via nucleofection, excluding the risk of mutations associated with viral transduction. Different in vitro end-point and real-time assays of the CAR lymphocyte antitumor cytotoxicity and in vivo human HER2-positive tumor xenograft mice model proved potent cytotoxic activity of the generated CAR-T-NK cells. Our data suggest transient expression of anti-HER2 CARs in plasmid vectors by human lymphocytes as a safer treatment for HER2-positive human cancers. We also conducted preliminary investigations to elucidate if fucosylated chondroitin sulfate may be used as a possible agent to decrease excessive cytokine production without negative impact on the CAR lymphocyte antitumor effect.

Extracellular volume fraction determined by equilibrium contrast-enhanced computed tomography: correlation with histopathological findings in gastric cancer

PURPOSE

To assess the relationship between histopathological features of gastric cancer and the extracellular volume fraction (ECV) measured by preoperative equilibrium contrast-enhanced computed tomography (CECT).

MATERIALS AND METHODS

The study group consisted of 66 patients with surgically resected gastric adenocarcinoma who underwent preoperative multiphasic CECT. Tumor ECVs were calculated using region-of-interest measurements within the gastric cancer and aorta of each case on unenhanced and equilibrium-phase images. The relationship between the mean ECV values and clinicopathological parameters was examined by univariate analysis. Parameters showing a significant difference in the former test were further tested by linear regression and receiver operating characteristic (ROC) curve analyses.

RESULTS

In the univariate analysis, the values of venous invasion (p = 0.0487) and tumor infiltration (INF) pattern (p < 0.0001) were significantly correlated with the tumor ECV. INF was significantly correlated (β = 0.57, p < 0.0001) in the linear regression analysis. The tumor ECV showed better diagnostic accuracy for predicting INF (INFa/b vs INFc), and the area under the ROC curve value was 0.89.

CONCLUSION

Tumor ECV determined by equilibrium CECT is significantly correlated with the pathological INF of gastric cancer.

Emerging Targeted Therapies for HER2-Positive Breast Cancer

Breast cancer is the most common cancer in women and the leading cause of death. HER2 overexpression is found in approximately 20% of breast cancers and is associated with a poor prognosis and a shorter overall survival. Tratuzumab, a monoclonal antibody directed against the HER2 receptor, is the standard of care treatment. However, a third of the patients do not respond to therapy. Given the high rate of resistance, other HER2-targeted strategies have been developed, including monoclonal antibodies such as pertuzumab and margetuximab, trastuzumab-based antibody drug conjugates such as trastuzumab-emtansine (T-DM1) and trastuzumab-deruxtecan (T-DXd), and tyrosine kinase inhibitors like lapatinib and tucatinib, among others. Moreover, T-DXd has proven to be of use in the HER2-low subtype, which suggests that other HER2-targeted therapies could be successful in this recently defined new breast cancer subclassification. When patients progress to multiple strategies, there are several HER2-targeted therapies available; however, treatment options are limited, and the potential combination with other drugs, immune checkpoint inhibitors, CAR-T cells, CAR-NK, CAR-M, and vaccines is an interesting and appealing field that is still in development. In this review, we will discuss the highlights and pitfalls of the different HER2-targeted therapies and potential combinations to overcome metastatic disease and resistance to therapy.

Deviating HER2 test results in gastric cancer: analysis from the prospective multicenter VARIANZ study

PURPOSE

The prospective multicenter VARIANZ study aimed to identify resistance biomarkers for HER2-targeted treatment in advanced gastric and esophago-gastric junction cancer (GC, EGJC). HER2 test deviations were found in 90 (22.3%) of 404 cases (central versus local testing) and were associated with negative impact on survival for trastuzumab-treated patients. Here, we investigated methodological and biological variables that may promote deviating HER2 test results.

METHODS

We analyzed HER2 testing procedures and participation in quality assurance programs of 105 participating local pathology laboratories. Furthermore, tumor localization and histological subtypes were compared between patients with centrally confirmed (central HER2 + /local HER2 + , n = 68) and unconfirmed HER2 status (central HER2 -/local HER2 + , n = 68).

RESULTS

For central HER2 testing, concordance between in situ hybridization (ISH) and immunohistochemistry (IHC) was 98.3%, with IHC sensitivity of 93.3% (84 IHC + of 90 ISH +), specificity of 99.5% (389 IHC- of 391 ISH-), and a positive diagnosis rate of 97.7%. Central confirmation of the local HER2 IHC scores were seen for the majority of locally HER2- IHC 0/1 (172/178; 96.6%), but less frequently for locally IHC3 + (57/124; 46.0%) cases. Deviation rate was not associated with IHC antibody platform used in the local pathology institute neither with participation in quality-assuring tests. Regarding tumor characteristics, deviating test results were more frequently found in GC vs. EGJC (69.1% vs. 39.7%; p = 0.001) and in Laurén diffuse vs. intestinal subtype (23.5% vs. 5.9%, p = 0.004).

CONCLUSION

Tumor localization and histological subtype have an impact on HER2 test deviation rates. Assessment of HER2 remains challenging for GC and EGJC.

Human epidermal growth factor receptor-2 gene expression positivity determined by silver in situ hybridization/immunohistochemistry methods and associated factors in a cohort of Sri Lankan patients with gastric adenocarcinoma: a prospective study

OBJECTIVE

Positive human epidermal growth factor 2 (HER2) expression and its predictive clinicopathological features remain unclear in Sri Lankan gastric cancer (GC) patients. Here, we aimed to determine GC HER2 status predictors by analyzing associations between clinicopathological features and HER2 expression using immunohistochemistry (IHC) and silver in situ hybridization (SISH).

METHODS

During this 4-year prospective study, clinicopathological data were collected from participants in the National Hospital of Sri Lanka. HER2 IHC and SISH were performed using commercial reagents. Using chi-square tests, associations of HER2-IHC/SISH with clinicopathological features were analyzed.

RESULTS

Overall, 145 GC patients were included, 69 had gastrectomies and 76 had biopsies. Positive HER2 expression by IHC was associated with age <60 years, high T stage (assessed pathologically in resections and radiologically in biopsies), high nuclear grade, tumor necrosis, mitosis >5/high-power field, with additional perineural invasion and lymphovascular invasion in resections. These features, excluding lymphovascular invasion but including male sex, were associated with HER2 expression by SISH.

CONCLUSIONS

Age <60 years, high nuclear grade, tumor necrosis, and perineural invasion are associated factors of HER2 status. These could be used to triage GC patients for HER2 status testing in limited resource settings where IHC/SISH analysis is costly.

Morpho-functional analysis of patient-derived xenografts reveals differential impact of gastric cancer and chemotherapy on the tumor ecosystem, affecting immune check point, metabolism, and sarcopenia

OBJECTIVES

Gastric cancer (GC) is an aggressive disease due to late diagnosis resulting from the lack of easy diagnostic tools, resistances toward immunotherapy (due to low PD-L1 expression), or chemotherapies (due to p53 mutations), and comorbidity factors, notably muscle atrophy. To improve our understanding of this complex pathology, we established patient-derived xenograft (PDX) models and characterized the tumor ecosystem using a morpho-functional approach combining high-resolution imaging with molecular analyses, regarding the expression of relevant therapeutic biomarkers and the presence of muscle atrophy.

MATERIALS AND METHODS

GC tissues samples were implanted in nude mice. Established PDX, treated with cisplatin or not, were imaged by magnetic resonance imaging (MRI) and analyzed for the expression of relevant biomarkers (p53, PD-L1, PD-1, HER-2, CDX2, CAIX, CD31, a-SAM) and by transcriptomics.

RESULTS

Three well-differentiated, one moderately and one poorly differentiated adenocarcinomas were established. All retained the architectural and histological features of their primary tumors. MRI allowed in-real-time evaluation of differences between PDX, in terms of substructure, post-therapeutic changes, and muscle atrophy. Immunohistochemistry showed differential expression of p53, HER-2, CDX2, a-SAM, PD-L1, PD-1, CAIX, and CD31 between models and upon cisplatin treatment. Transcriptomics revealed treatment-induced hypoxia and metabolic reprograming in the tumor microenvironment.

CONCLUSION

Our PDX models are representative for the heterogeneity and complexity of human tumors, with differences in structure, histology, muscle atrophy, and the different biomarkers making them valuable for the analyses of the impact of platinum drugs or new therapies on the tumor and its microenvironment.

Evaluation of Human Epidermal Growth Factor Receptor 2 Expression in Gastric and Gastroesophageal Cancers in Tanzania

CONTEXT.—

The incidence of human epidermal growth factor receptor 2 (HER2) positivity in gastric cancers differs widely across various populations and is unknown in many low-resource settings.

OBJECTIVE.—

To evaluate the rates of HER2 positivity in gastric and gastroesophageal adenocarcinoma at a national referral hospital in East Africa. We also assessed the association between HER2 overexpression and patient clinicopathologic characteristics.

DESIGN.—

A retrospective review of cases diagnosed as either gastric or gastroesophageal adenocarcinoma between 2013 and 2017 was performed at Muhimbili National Hospital in Dar es Salaam, Tanzania. Of 1205 specimens meeting inclusion criteria, stratified random sampling was conducted to select 150 cases for HER2 immunohistochemistry and clinicopathologic analysis.

RESULTS.—

The median age of patients was 56.5 years, with 65.3% (98 of 150) of the cohort composed of male patients, and 34.7% (52 of 150) of female patients. HER2 overexpression was identified in 6.0% (9 of 150) of cases. Approximately half of the tumors (51.3%; 77 of 150) were intestinal-type gastric adenocarcinoma, and 36.0% (54 of 150) were moderately differentiated. Intestinal-type (P = .01) and well-differentiated tumors (P = .001) were associated with HER2 overexpression.

CONCLUSIONS.—

HER2 overexpression was primarily seen in intestinal-type and well-differentiated tumors. Therefore, prioritizing HER2 testing for patients with intestinal-type, well-differentiated, or moderately differentiated gastric and gastroesophageal adenocarcinomas may be appropriate in Tanzania in efforts to allocate testing for patients who are most likely to benefit from trastuzumab therapy.

Prevalence of Her2-neu status and its clinicopathological association in newly diagnosed gastric cancer patients

Background

This study aimed to report the prevalence of HER2-neu in newly diagnosed early or metastatic gastric cancer (GC) patients, to determine the percentage of patients achieving various IHC scores correlating with the ISH results and to establish a database for GC patients in Lebanon.

Methods

This was a national, multicenter, descriptive and cross-sectional study in patients with histologically confirmed early or metastatic GC newly diagnosed. All eligible patients underwent the IHC and ISH tests in a central laboratory. Demographics, medical history and histopathology data were collected.

Results

One hundred fifty-seven patients were included (mean age at diagnosis: 63 ± 14.1 years) during a 3.5 year period. The prevalence of HER2-neu over expression was 21% (95% CI: 15.3–27.4) using ICH and ISH. Agreement between IHC and ISH results was significantly substantial (kappa = 0.681; p-value < 0.001). Over expressed HER2-neu status was significantly associated with high ECOG performance status only.

Conclusions

The prevalence of HER2-neu over expression in newly diagnosed early or metastatic GC patients seemed to be high in Lebanon. The database generated allows to monitor trends in the epidemiology and management of GC.

HER2 in Uterine Serous Carcinoma: Testing platforms and implications for targeted therapy

OBJECTIVE

HER2 is an important prognostic and therapeutic target in uterine serous carcinoma (USC). Optimal HER2 testing platforms have not been defined and guidelines for testing have changed over time. Our objective is to assess the concordance of HER2 positivity based on chromogenic in situ hybridization (CISH), immunohistochemistry (IHC), and next generation sequencing (NGS) and to determine the rate of downstream mutations that may affect response to HER2 directed therapy.

METHODS

Utilizing the Caris tumor registry, 2192 USC tumors were identified and analyzed using NGS (NextSeq, 592 Genes and WES, NovaSEQ), IHC, and CISH. PD-L1 expression was tested by IHC. Microsatellite instability was tested by fragment analysis, IHC, and NGS. Tumor mutational burden (TMB) was measured by totaling somatic mutations per tumor. HER2 positivity through IHC and CISH was determined based on 2007 and 2018 ASCO/CAP HER2 breast cancer guidelines.

RESULTS

There was a higher rate of HER2 positivity by IHC when using the 2018 guidelines compared to the 2007 guidelines (16.3% vs 12.3%). Concordance between IHC and CISH was 98.9%. ERBB2 amplification was identified by NGS in 10.5% of tumors. Compared to CISH results, this corresponds to a concordance rate of 91.6% and a positive predictive value (PPV) of 60.3%. Single gene alterations in HER2 amplified tumors that may implicate HER2 therapy resistance included PI3K (33.1%), KRAS (2.5%), and PTEN (1.3%).

CONCLUSIONS

There was high concordance between HER2 positivity based on CISH and IHC. Rate of HER2 positivity is the lowest by NGS. Ultimately these testing platforms need to be validated by response to targeted therapy.

Molecular Pathology of Gastric Cancer

Gastric cancer (GC) is one of the most common lethal malignant neoplasms worldwide, with limited treatment options for both locally advanced and/or metastatic conditions, resulting in a dismal prognosis. Although the widely used morphological classifications may be helpful for endoscopic or surgical treatment choices, they are still insufficient to guide precise and/or personalized therapy for individual patients. Recent advances in genomic technology and high-throughput analysis may improve the understanding of molecular pathways associated with GC pathogenesis and aid in the classification of GC at the molecular level. Advances in next-generation sequencing have enabled the identification of several genetic alterations through single experiments. Thus, understanding the driver alterations involved in gastric carcinogenesis has become increasingly important because it can aid in the discovery of potential biomarkers and therapeutic targets. In this article, we review the molecular classifications of GC, focusing on The Cancer Genome Atlas (TCGA) classification. We further describe the currently available biomarker-targeted therapies and potential biomarker-guided therapies. This review will help clinicians by providing an inclusive understanding of the molecular pathology of GC and may assist in selecting the best treatment approaches for patients with GC.

Poorly cohesive cells gastric carcinoma including signet-ring cell cancer: Updated review of definition, classification and therapeutic management

While the incidence of gastric cancer (GC) in general has decreased worldwide in recent decades, the incidence of diffuse cancer historically comprising poorly cohesive cells-GC (PCC-GC) and including signet ring cell cancer is rising. Literature concerning PCC-GC is scarce and unclear, mostly due to a large variety of historically used definitions and classifications. Compared to other histological subtypes of GC, PCC-GC is nevertheless characterized by a distinct set of epidemiological, histological and clinical features which require a specific diagnostic and therapeutic approach. The aim of this review was to provide an update on the definition, classification and therapeutic strategies of PCC-GC. We focus on the updated histological definition of PCC-GC, along with its implications on future treatment strategies and study design. Also, specific considerations in the diagnostic management are discussed. Finally, the impact of some recent developments in the therapeutic management of GC in general such as the recently validated taxane-based regimens (5-Fluorouracil, leucovorin, oxaliplatin and docetaxel), the use of hyperthermic intraperitoneal chemotherapy as well as pressurized intraperitoneal aerosol chemotherapy and targeted therapy have been reviewed in depth for their relative importance for PCC-GC in particular.

Relationship between HER2 overexpression and long-term outcomes of early gastric cancer: a prospective observational study with a 6-year follow-up

Background

Studies have confirmed the prognostic value of the expression status of human epidermal growth factor receptor 2 (HER2) in advanced gastric cancer. However, its role in early gastric cancer (EGC) remains largely unknown. This study explored the association between HER2 overexpression and clinical outcomes of patients with EGC.

Methods

A total of 211 patients who had undergone endoscopic treatment for pN0 EGC were enrolled. The HER2 expression status was assessed using immunohistochemistry (IHC).

Results

The prevalence of HER2 overexpression was 14.2%. HER2 overexpression showed a significant correlation with tumor location (P = 0.033). Multivariate analysis showed that HER2 overexpression was significantly associated with an increased risk of tumor recurrence in pN0 EGC (hazard ratio [HR] = 3.97; 95% confidence interval [CI] 1.30–12.14; P = 0.016) but not overall survival (OS) or disease-specific survival (DSS). Of the included patients, age was associated with OS (HR = 1.11; 95% CI 1.04–1.18; P = 0.002], whereas lymphovascular invasion was significantly associated with poor DSS (HR = 33.66; 95% CI 3.05–371.25; P = 0.004).

Conclusion

This study shows that HER2 overexpression is significantly associated with tumor recurrence in pN0 EGC. Hence, Her2 testing at diagnosis is important and differential treatment and/or follow up strategies for patients with Her2 overexpression may merit future study.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02309-7.

Gastric Cancer, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology

Gastric cancer is the third leading cause of cancer-related deaths worldwide. Over 95% of gastric cancers are adenocarcinomas, which are typically classified based on anatomic location and histologic type. Gastric cancer generally carries a poor prognosis because it is often diagnosed at an advanced stage. Systemic therapy can provide palliation, improved survival, and enhanced quality of life in patients with locally advanced or metastatic disease. The implementation of biomarker testing, especially analysis of HER2 status, microsatellite instability (MSI) status, and the expression of programmed death-ligand 1 (PD-L1), has had a significant impact on clinical practice and patient care. Targeted therapies including trastuzumab, nivolumab, and pembrolizumab have produced encouraging results in clinical trials for the treatment of patients with locally advanced or metastatic disease. Palliative management, which may include systemic therapy, chemoradiation, and/or best supportive care, is recommended for all patients with unresectable or metastatic cancer. Multidisciplinary team management is essential for all patients with localized gastric cancer. This selection from the NCCN Guidelines for Gastric Cancer focuses on the management of unresectable locally advanced, recurrent, or metastatic disease.

Disruption of Her2-Induced PD-L1 Inhibits Tumor Cell Immune Evasion in Patient-Derived Gastric Cancer Organoids

Simple Summary

HER2 may contribute to immune evasion in gastric cancer that is associated with PD-L1 expression. Autologous organoid/immune cell co-cultures serve as an appropriate in vitro model to study the effects of anti-HER2 targeted therapy in combination with anti-PD1 immune checkpoint inhibition and may be used as an ex vivo tool for precision medicine.

Abstract

(1) Background: The expression of programmed death-ligand 1 (PD-L1), which interacts with programmed cell death protein 1 (PD-1) on cytotoxic T lymphocytes (CTLs), enables tumors to escape immunosurveillance. The PD-1/PD-L1 interaction results in the inhibition of CTL proliferation, and effector function, thus promoting tumor cell evasion from immunosurveillance and cancer persistence. Despite 40% of gastric cancer patients exhibiting PD-L1 expression, only a small subset of patients responds to immunotherapy. Human epidermal growth factor receptor2 (HER2) is one of the critical regulators of several solid tumors, including metastatic gastric cancer. Although half of PD-L1-positive gastric tumors co-express HER2, crosstalk between HER2 and PD-1/PD-L1 in gastric cancer remains undetermined. (2) Methods: Human gastric cancer organoids (huTGOs) were generated from biopsied or resected tissues and co-cultured with CTLs and myeloid-derived suppressor cells (MDSCs). Digital Spatial Profiling (DSP) was performed on FFPE tissue microarrays of numerous gastric cancer patients to examine the protein expression of immune markers. (3) Results: Knockdown of HER2 in PD-L1/HER2-positive huTGOs led to a concomitant decrease in PD-L1 expression. Similarly, in huTGOs/immune cell co-cultures, PD-L1 expression decreased in huTGOs and was correlated with an increase in CTL proliferation which enhanced huTGO death. Treatment with Nivolumab exhibited similar effects. However, a combinatorial treatment with Mubritinib and Nivolumab was unable to inhibit HER2 expression in co-cultures containing MDSCs. (4) Conclusions: Our study suggested that co-expression of HER2 and PD-L1 may contribute to tumor cell immune evasion. In addition, autologous organoid/immune cell co-cultures can be exploited to effectively screen responses to a combination of anti-HER2 and immunotherapy to tailor treatment for gastric cancer patients.

Differential Expression of COL1A1, COL1A2, COL6A3, and SULF1 as Prognostic Biomarkers in Gastric Cancer

Background

Gastric cancer (GC) is among the most prevalent cancers globally. As such, there is a need to explore the mechanism underlying its pathogenesis and identify potential biomarkers for its prognosis.

Methods

ONCOMINE was used to screen differentially expressed genes between GC and normal gastric mucosa. GEPIA was used to analyze the expression and correlation of candidate genes in tumor node metastasis (TNM) stage. STRING was used to construct protein interaction network. Kaplan-Meier plotter was used to analyze survival. TIMER was used to evaluate the association between candidate genes and immune cell infiltration.

Results

From the ONCOMINE database, we found COL1A1, COL1A2, COL6A3, and SULF1 genes were significantly upregulated in stomach adenocarcinomas. There was a considerable correlation between the expression of COL1A1 (p = 0.029), COL1A2 (p = 0.004), COL6A3 (p = 0.002), SULF1 (p = 0.001), and the TNM stage. COL1A1 was positively correlated with ERBB2 (R = -0.037, p = 0.46), while the other three genes were negatively correlated with ERBB2 (p > 0.05). The Kaplan-Meier plotter showed that low transcriptional levels of COL1A1 (p = 0.0020), COL1A2 (p = 0.0015), COL6A3 (p = 0.0015), and SULF1 (p = 0.0016) in gastric cancer patients were remarkably related to longer overall survival. In addition, there was a close relationship between chemokine expression and infiltration of the six immune cell types: B cells, macrophages, CD4+ T cells, CD8+ T cells, dendritic cells, and neutrophils, implying that the genes acted as indicators of both prognosis and immune status.

Conclusion

Our findings implicate COL1A1, COL1A2, COL6A3, and SULF1 as candidate biomarkers for the prognosis of gastric cancer.

First-line nivolumab plus chemotherapy versus chemotherapy alone for advanced gastric, gastro-oesophageal junction, and oesophageal adenocarcinoma (CheckMate 649): a randomised, open-label, phase 3 trial

BACKGROUND

First-line chemotherapy for advanced or metastatic human epidermal growth factor receptor 2 (HER2)-negative gastric or gastro-oesophageal junction adenocarcinoma has a median overall survival (OS) of less than 1 year. We aimed to evaluate first-line programmed cell death (PD)-1 inhibitor-based therapies in gastric, gastro-oesophageal junction, and oesophageal adenocarcinoma. We report the first results for nivolumab plus chemotherapy versus chemotherapy alone.

METHODS

In this multicentre, randomised, open-label, phase 3 trial (CheckMate 649), we enrolled adults (≥18 years) with previously untreated, unresectable, non-HER2-positive gastric, gastro-oesophageal junction, or oesophageal adenocarcinoma, regardless of PD-ligand 1 (PD-L1) expression from 175 hospitals and cancer centres in 29 countries. Patients were randomly assigned (1:1:1 while all three groups were open) via interactive web response technology (block sizes of six) to nivolumab (360 mg every 3 weeks or 240 mg every 2 weeks) plus chemotherapy (capecitabine and oxaliplatin every 3 weeks or leucovorin, fluorouracil, and oxaliplatin every 2 weeks), nivolumab plus ipilimumab, or chemotherapy alone. Primary endpoints for nivolumab plus chemotherapy versus chemotherapy alone were OS or progression-free survival (PFS) by blinded independent central review, in patients whose tumours had a PD-L1 combined positive score (CPS) of five or more. Safety was assessed in all patients who received at least one dose of the assigned treatment. This study is registered with ClinicalTrials.gov, NCT02872116.

FINDINGS

From March 27, 2017, to April 24, 2019, of 2687 patients assessed for eligibility, we concurrently randomly assigned 1581 patients to treatment (nivolumab plus chemotherapy [n=789, 50%] or chemotherapy alone [n=792, 50%]). The median follow-up for OS was 13·1 months (IQR 6·7-19·1) for nivolumab plus chemotherapy and 11·1 months (5·8-16·1) for chemotherapy alone. Nivolumab plus chemotherapy resulted in significant improvements in OS (hazard ratio [HR] 0·71 [98·4% CI 0·59-0·86]; p<0·0001) and PFS (HR 0·68 [98 % CI 0·56-0·81]; p<0·0001) versus chemotherapy alone in patients with a PD-L1 CPS of five or more (minimum follow-up 12·1 months). Additional results showed significant improvement in OS, along with PFS benefit, in patients with a PD-L1 CPS of one or more and all randomly assigned patients. Among all treated patients, 462 (59%) of 782 patients in the nivolumab plus chemotherapy group and 341 (44%) of 767 patients in the chemotherapy alone group had grade 3-4 treatment-related adverse events. The most common any-grade treatment-related adverse events (≥25%) were nausea, diarrhoea, and peripheral neuropathy across both groups. 16 (2%) deaths in the nivolumab plus chemotherapy group and four (1%) deaths in the chemotherapy alone group were considered to be treatment-related. No new safety signals were identified.

INTERPRETATION

Nivolumab is the first PD-1 inhibitor to show superior OS, along with PFS benefit and an acceptable safety profile, in combination with chemotherapy versus chemotherapy alone in previously untreated patients with advanced gastric, gastro-oesophageal junction, or oesophageal adenocarcinoma. Nivolumab plus chemotherapy represents a new standard first-line treatment for these patients.

FUNDING

Bristol Myers Squibb, in collaboration with Ono Pharmaceutical.

Assessment of Systemic Inflammatory Response and Nutritional Markers in Patients With Trastuzumab-treated Unresectable Advanced Gastric Cancer

AIM

To determine whether markers of systemic inflammatory response and nutrition are a predictor of treatment response in patients with trastuzumab-treated unresectable advanced gastric cancer.

PATIENTS AND METHODS

Twenty-one patients who received chemotherapy for unresectable advanced gastric cancer at Kochi Medical School from 2013 to 2020 were enrolled. Clinicopathological information and systemic inflammatory response data were obtained retrospectively to investigate associations between baseline cancer-related prognostic variables and survival outcomes.

RESULTS

The median overall survival (OS) and progression-free survival (PFS) for the whole cohort were 24.5 (range=1.9-88.4) months and 7.0 (range=2.0-23.4) months, respectively. The objective response rate and disease control rate were 52.4% and 81.0%, respectively. The median PFS for patients with a neutrophil to lymphocyte ratio (NLR) <2.8 was significantly longer than that for those with NLR ≥2.8 (8.9 vs. 6.0 months; p=0.048). Although the median OS also tended to be longer for patients with NLR <2.8, the difference was not statistically significant. No significant differences in median OS and PFS were observed between patients with a prognostic nutrition index (PNI) <41.6 and those with PNI ≥41.6.

CONCLUSION

An NLR ≥2.8 is a predictor of poorer prognosis in patients receiving systemic treatment with trastuzumab and chemotherapy for unresectable advanced or recurrent gastric cancer.

A Reliable and Standardizable Differential PCR and qPCR Methodology Assesses HER2 Gene Amplification in Gastric Cancer

We have applied two PCR techniques, differential PCR (diffPCR) and qPCR for the identification of HER2 gene amplifications in genomic DNA of tumor and distal gastric samples from patients with gastric cancer. The diffPCR technique consists of the simultaneous amplification of the HER2 gene and a housekeeping gene by conventional PCR and the densitometric analysis of the bands obtained. We established a cut-off point based on the mean and standard deviation analyzing the DNA of 30 gastric tissues from patients undergoing non-cancer gastrectomy. diffPCR and qPCR yielded consistent results. HER2-overexpression was detected in 25% of patients and was further confirmed by immunohistochemistry and immunofluorescence. The approaches herein described may serve as complementary and reliable methods to assess HER2 amplification.

Durable Clinical Response to Immune and Targeted Therapies in an Elderly Man with Synchronous Gastric (HER2+) and Bladder Cancers: Case Report and Literature Review

Synchronous occurrences of gastric cancer positive for human epidermal growth factor receptor 2 (HER2+) and bladder cancer are rarely encountered in clinical practice. When and how to effectively treat both tumors, without compounding adverse effects, must be addressed. Herein, we describe an elderly man who presented with both gastric cancer (HER2+) and bladder cancer. Due to enlarged and fused lymph nodal metastasis, he was ill-suited for stomach resection. After transurethral resection of the bladder tumor, we administered both chemotherapy and the targeted agent trastuzumab. Gastric cancer showed partial response however bladder cancer recurred following two cycles of this regimen, the adverse effects were prohibitive, prompting refusal of further chemotherapy and radiotherapy. He then received the immune checkpoint inhibitor (ICI) nivolumab and trastuzumab in combination. This particular regimen successfully controlled both cancers and substantially improved the patient’s quality of life. Its long-term use did not intensify adverse reactions, enabling a progression-free survival of 21 months to date. We have also reviewed other published clinical strategies applied in rare instances of multiple primary malignancies as a reference for treating such patients.

Mining the plasma-proteome associated genes in patients with gastro-esophageal cancers for biomarker discovery

Gastro-esophageal (GE) cancers are one of the major causes of cancer-related death in the world. There is a need for novel biomarkers in the management of GE cancers, to yield predictive response to the available therapies. Our study aims to identify leading genes that are differentially regulated in patients with these cancers. We explored the expression data for those genes whose protein products can be detected in the plasma using the Cancer Genome Atlas to identify leading genes that are differentially regulated in patients with GE cancers. Our work predicted several candidates as potential biomarkers for distinct stages of GE cancers, including previously identified CST1, INHBA, STMN1, whose expression correlated with cancer recurrence, or resistance to adjuvant therapies or surgery. To define the predictive accuracy of these genes as possible biomarkers, we constructed a co-expression network and performed complex network analysis to measure the importance of the genes in terms of a ratio of closeness centrality (RCC). Furthermore, to measure the significance of these differentially regulated genes, we constructed an SVM classifier using machine learning approach and verified these genes by using receiver operator characteristic (ROC) curve as an evaluation metric. The area under the curve measure was > 0.9 for both the overexpressed and downregulated genes suggesting the potential use and reliability of these candidates as biomarkers. In summary, we identified leading differentially expressed genes in GE cancers that can be detected in the plasma proteome. These genes have potential to become diagnostic and therapeutic biomarkers for early detection of cancer, recurrence following surgery and for development of targeted treatment.

Primary Tumor Location Is a Predictor of Poor Prognosis in Patients with Locally Advanced Esophagogastric Cancer Treated with Perioperative Chemotherapy

BACKGROUND

Esophagogastric cancer (EGC) is a leading neoplasm worldwide. Perioperative chemotherapy (periCT) is currently a standard of care for most patients (pts). Prevalence of esophagogastric junction (EGJ) tumors is increasing over the last years.

METHODS

The aim of this study was to retrospectively search for prognostic factors in pts. with locally advanced EGC treated with periCT. Three-year overall survival (OS) and Event-Free Survival (EFS) were main end-points. HER-2 positive tumors were defined by immunohistochemistry or FISH.

RESULTS

Between June/2007 and November/2015, 128 pts. started periCT for esophagogastric junction (EGJ) or gastric adenocarcinoma (GC). Median age was 59.5 y and 64% were male. Primary site was EGJ in 27% and 65% were cN+. Diffuse subtype was seen in 42%. Ninety-seven pts. were assessed for HER-2; 14 (14.4%) were positive. After median follow-up time of 45 m, 48 deaths occurred. The 3-year OS and EFS rate was 61.3% and 51.2%, respectively. Main prognostic factors were: AJCC ypT3-T4yN1-N3 (HR 6.75 p 0.002) and EGJ primary (HR 2.64, p 0.004). Overall HER-2 was not prognostic. Still, a difference in 3-year OS was observed for GC/HER2+ compared to EGJ/HER2+ (88.9% versus 20%, p = 0.002). This difference is greater for 3-year EFS with no patient with EGJ/HER2+ free-of-event against 62.5% for GC/HER+ (p = 0.011).

CONCLUSION

In our analysis, pathological staging and primary site were main prognostic factors. Moreover, a small group of EGJ/HER2+ had very poor survival.

Tucatinib Inhibits Renal Transporters OCT2 and MATE Without Impacting Renal Function in Healthy Subjects

Tucatinib is a potent tyrosine kinase inhibitor selective for human epidermal growth factor receptor 2 (HER2) approved by the US Food and Drug Administration for the treatment of HER2‐positive metastatic breast cancer and in development for other HER2‐positive solid tumors. Modest, reversible serum creatinine (SCr) elevations have been observed in tucatinib clinical trials. SCr is conveyed by the renal drug transporters organic cation transporter 2 (OCT2) and multidrug and toxin extrusion protein 1 (MATE1) and 2‐K (MATE2‐K) and can increase in the presence of inhibitors of these transporters. In vitro, tucatinib inhibited OCT2‐, MATE1‐, and MATE2‐K‐mediated transport of metformin, with IC₅₀ values of 14.7, 0.340, and 0.135 µM, respectively. Tucatinib also inhibited OCT2‐ and MATE1‐mediated transport of creatinine, with IC₅₀ values of 0.107 and 0.0855 µM, respectively. A phase 1 study with metformin administered orally in the absence and presence of tucatinib was conducted in 18 healthy subjects. Renal function was assessed by measuring glomerular filtration rate (GFR; based on iohexol plasma clearance) and endogenous markers (SCr, cystatin C‐based estimated glomerular filtration rate [eGFR]) with and without tucatinib. Metformin exposure increased (1.4‐fold) and renal clearance decreased (29.99‐17.64 L/h) with tucatinib, with no effect on metformin maximum concentration. Creatinine clearance transiently decreased 23% with tucatinib. GFR and eGFR, which are unaffected by OCT2 and/or MATE1/2‐K transport, were unchanged with tucatinib. These data demonstrate that tucatinib inhibits OCT2‐ and MATE1/2‐K‐mediated tubular secretion of creatinine, which may manifest as mild SCr elevations that are not indicative of renal impairment.

Human epidermal growth factor 2 (HER2) in early stage uterine serous carcinoma: A multi-institutional cohort study

BACKGROUND

Human epidermal growth factor receptor 2 (HER2) has emerged as an important prognostic and therapeutic target in advanced stage and recurrent uterine serous carcinoma (USC). The significance of tumoral HER2 expression in early-stage disease has not been established.

METHODS

This multi-center cohort study included women with stage I USC treated from 2000 to 2019. Demographic, treatment, recurrence, and survival data were collected. Immunohistochemistry (IHC) was performed for HER2 and scored 0-3+. Equivocal IHC results (2+) were further tested with fluorescence in-situ hybridization (FISH). HER2 positivity was defined as 3+ IHC or FISH positive.

RESULTS

One hundred sixty-nine patients with stage I USC were tested for HER2; 26% were HER2-positive. There were no significant differences in age, race, stage, adjuvant therapy, or follow-up duration between the HER2-positive and negative cohorts. Presence of lymph-vascular space invasion was correlated with HER2-positive tumors (p = .003). After a median follow-up of 50 months, there were 43 (25.4%) recurrences. There were significantly more recurrences in the HER2-positive cohort (50.0% vs 16.8%, p < .001). HER2 positive tumors were associated with worse progression-free (PFS) and overall survival (OS) (p < .001 and p = .024). On multivariate analysis, HER2 positive tumors were associated with inferior PFS (aHR 3.50, 95%CI 1.84-6.67; p < .001) and OS (aHR 2.00, 95%CI 1.04-3.88; p = .039) compared to HER2-negative tumors.

CONCLUSIONS

Given its significant association with worse recurrence and survival outcomes, HER2 positivity appears to be a prognostic biomarker in women with stage I uterine serous carcinoma. These data provide support for clinical trials with anti-HER2-directed therapy in early-stage disease.

Current Molecular Targeted Agents for Advanced Gastric Cancer

Gastric cancer is the third leading cause of malignant tumor-related mortality worldwide. Traditional cytotoxic agents prolong the overall survival and progression-free survival of patients with advanced gastric cancer (AGC) compared to that with best supportive care. Due to the occurrence of serious adverse drug reactions that result in discontinued treatment, the survival benefit in AGC remains unsatisfactory. Systemic chemotherapy regimens have changed greatly, especially since the introduction of trastuzumab. Nevertheless, HER2 positivity is present in only approximately 20% of tumors. Due to the genetic heterogeneity and complexity of patients, there are many studies in progress that are exploring novel targeted drugs as an alternative to chemotherapy or adjuvant treatment in early-stage, progressive, and advanced gastric cancer. On the basis of the differences in gene expression profiles among patients, searching for specific and sensitive predictive biomarkers is important for identifying patients who will benefit from a specific targeted drug. With the development of targeted therapies and available chemotherapeutic drugs, there is no doubt that, over time, more patients will achieve better survival outcomes. Recently, immune checkpoint blockade has been well developed as a promising anticancer strategy. This review outlines the currently available information on clinically tested molecular targeted drugs and immune checkpoint inhibitors for AGC to provide support for decision-making in clinical practice.

A Modified ypTNM Staging System-Development and External Validation of a Nomogram Predicting the Overall Survival of Gastric Cancer Patients Received Neoadjuvant Chemotherapy

Purpose

Neoadjuvant chemotherapy is now widely used in gastric cancer patients. However, the current 8th ypTNM staging system is developed based on patients with less extensive lymph node dissection and the predictive value is relatively limited. In this study, we aim to develop and validate a nomogram that predicts overall survival in gastric cancer patients received neoadjuvant chemotherapy.

Patients and Methods

From January, 2007 to December, 2014, 471 patients receiving neoadjuvant chemotherapy at our center were enrolled in the study. Based on the Cox proportional hazard model, a nomogram was developed from them and then an external validation was conducted on a cohort of 239 patients from another cancer center.

Results

The overall survival (OS) rates of 1 year and 3 years were 90.0% and 64.1%, respectively. Body mass index category, tumor location, T stage and N stage were independent prognostic factors for the survival outcome. The C-index of the model was 0.74 in the development cohort and 0.69 in the validation cohort. Our nomogram also showed good calibration in both cohorts.

Conclusion

We developed and validated a nomogram to predict the 1- and 3-year OS of patients who received neoadjuvant chemotherapy and radical gastrectomy with D2 lymph node dissection. This nomogram predicts survival more accurately than the AJCC TNM staging system, which is the current golden standard.

Durable Clinical Response to Pyrotinib After Resistance to Prior Anti-HER2 Therapy for HER2-Positive Advanced Gastric Cancer: A Case Report

Background: Patients with advanced gastric cancer, especially the HER2-positive type, have a poor prognosis; there is a paucity of effective anti-HER2 drug therapies in patients who develop resistance to trastuzumab. Case presentation: We report the case of a 36-year-old male with HER2-positive gastric cancer with lung and liver metastases. The patient responded after treatment with trastuzumab combined with chemotherapy and attained a progression-free survival (PFS) of 17 months. Subsequently, the patient received apatinib that selectively inhibits the VEGFR2 and obtained an evident tumor response and a PFS of 8 months. When the disease progressed again, the regimen containing lapatinib failed. Then, the patient received treatment with nivolumab. However, he presented with hyper-progressive disease (HPD). Finally, he received a combination of capecitabine and pyrotinib, an irreversible dual TKI, acting on HER2 and EGFR. The tumor shrank markedly with this combination therapy. The mechanism of both HPD due to immunotherapy and the resistance to trastuzumab and lapatinib were investigated in this case. Loss of phosphatase and tensin homolog (PTEN) and new mutations of BRCA1 and KRAS were detected after resistance to trastuzumab and lapatinib. Conclusions: For patients with HER2-positive advanced gastric cancer who have developed resistance to trastuzumab, pyrotinib is a promising new agent, which can be used as salvage therapy.

Clinicopathological features and Borrmann classification associated with HER2-positive in primary gastric cancer

PURPOSE

Human epidermal growth factor receptor 2 (HER2) assesment is important for patients with advanced gastric cancer (GC) to determine trastuzumab therapy is being considered. A study was performed to evaluate the rate of HER2 positivity in patients with primary gastric cancer and to assess the relationship between HER2-positive and Borrmann classification.

PATIENTS AND METHODS

Four hundred and sixty-one patients with gastric or gastroesophageal junction cancer were confirmed as having adenocarcinoma between 2005 and 2016. HER2 status was assessed using immunohistochemistry (IHC) and/or fluorescence in situ hybridization (FISH). Tissues were considered to be HER2-positive when assessment revealed either an IHC score of 3+ or IHC score 2+ accompanied by a positive FISH result.

RESULTS

The HER2-positive rate was significantly higher in men than in women (19% vs 9%; p=0.006). In our study, HER2-positive gastric tumors with differentiated histology were significantly higher. The proportion of HER2-positive gastric tumors of Borrmann classification III or IV was significantly higher than tumors classified as I or II.

CONCLUSIONS

HER2-positive gastric cancer tends to be associated with male gender, differentiated histology, and Borrmann tumor classification of III or IV.

Prevalence of HER2 Expression and Its Correlation with Clinicopathological Parameters in Gastric or Gastroesophageal Junction Adenocarcinoma in North-East Indian Population

Objective: Human epidermal growth factor receptor 2 (erbb2/HER2) overexpression, has now been implicated in advanced gastric and gastroesophageal junction cancers. The study was conducted to determine the rate of HER2 positivity in patients with locally advanced or metastatic gastric and gastroesophageal adenocarcinoma in North-East India and to assess the impact of various demographic and clinical parameters on HER2 positivity. Methods: A total of 68 patients of age >18 years of gastric and gastroesophageal adenocarcinoma diagnosed on histopathological examination from September 2016 to February 2018 at Dr B Borooah Cancer Institute, Assam were enrolled for the observational (epidemiological) study. All patients were subjected to the HER2 immunohistochemistry test using a FDA-approved, standardized test kit. HER2 expression was correlated with various demographic and clinicopathological parameters. Results: The overall rate of HER2 positivity in the population studied was 56% (n=38). The rate was non-significantly higher in male, older age group (>60 years) and Hindu population. Similarly, HER2 positivity rate was higher in patients with well differentiated histology and was more common in patients with stage II and III diseases, but neither of the associations is statistically significant. HER2 positivity rate was significantly higher in proximal and in GEJ tumours (56% versus 44%, P=0.002). Conclusion: HER2 overexpression was evident in 56% of the North-East Indian patients with locally advanced and metastatic gastric and gastroesophageal adenocarcinoma. The overexpression correlated significantly with primary tumour site. Routine testing of gastric and gastroesophageal tumours for HER2 expression is recommended to provide a therapeutic advantage in Indian patients.

Significance of HER2 protein expression and HER2 gene amplification in colorectal adenocarcinomas

BACKGROUND

Human epidermal growth factor receptor 2 (HER2) is an oncogenic driver, and a well-established therapeutic target in breast and gastric cancers. While the role of HER2 as a prognostic biomarker in colorectal adenocarcinomas (CRCs) remains uncertain, its relevance as a therapeutic target has been established. We undertook the present study to evaluate the frequency of HER2 expression in CRC and to correlate it with various clinicopathological variables.

AIM

To correlate HER2 protein expression and HER2 gene amplification with clinicopathological features and survival in surgically resected CRC.

METHODS

About 1195 consecutive surgically resected CRCs were analyzed by immunohistochemical staining (IHC) to assess HER2 protein expression, and 141 selected tumors were further evaluated by fluorescence in situ hybridization (FISH) to assess HER2 gene amplification. Follow-up information was available for 1058 patients, and using this information we investigated the prevalence of HER2 protein overexpression and gene amplification in a large series of surgically resected CRCs, and evaluated the relationship between overexpression and clinicopathological parameters and prognosis.

RESULTS

HER2 IHC scores of 3+, 2+, 1+, and 0 were seen in 31 (2.6%), 105 (8.8%), 475 (39.7%), and 584 (48.9%) tumors, respectively. HER2 gene amplification was seen in 24/29 tumors with an IHC score of 3+ (82.8%; unreadable in 2/31), 12/102 tumors with an IHC score of 2+ (11.8%; unreadable in 2/104), and 0 tumors with IHC score of 1+ (0/10). HER2 gene amplification was seen in 36/1191 tumors (3.0%; unreadable in 4/1195). Among the tumors with HER2 IHC scores of 3+ and 2+, the mean percentage of tumor cells with positive IHC staining was 90% (median 100%, range 40%-100%) and 67% (median 75%, range 5%-95%), respectively (P < 0.05). Among tumors with IHC scores of 2+, those with HER2 gene amplification had a higher number of tumors cells with positive IHC staining (n = 12, mean 93%, median 95%, range 90%-95%) than those without (n = 90, mean 70%, median 50%, range 5%-95%) (P < 0.05). HER2 gene status was significantly associated with distant tumor metastasis and stage (P = 0.028 and 0.025). HER2 protein overexpression as measured by IHC or HER2 gene amplification as measured by FISH was not associated with overall survival (OS) or disease-specific survival for the overall group of 1058 patients. However, further stratification revealed that among patients with tubular adenocarcinomas who were 65 years old or younger (n = 601), those exhibiting HER2 gene amplification had a shorter OS than those without (mean: 47.9 mo vs 65.1 mo, P = 0.04). Among those patients with moderately to poorly differentiated tubular adenocarcinomas, those with positive HER2 tumor IHC scores (2+, 3+) had a shorter mean OS than those with negative HER2 IHC scores (0, 1+) (47.2 mo vs 64.8 mo, P = 0.033). Moreover, among patients with T2 to T4 stage tumors, those with positive HER2 IHC scores also had a shorter mean OS than those with negative HER2 IHC scores (47.1 mo vs 64.8 mo, P = 0.031).

CONCLUSION

HER2 protein levels are correlated with clinical outcomes, and positive HER2 expression as measured by IHC confers a worse prognosis in those patients 65 years old or younger with tubular adenocarcinomas.

Differential expression of EphA5 protein in gastric carcinoma and its clinical significance

The aim of the present study was to evaluate ephrin type-A receptor 5 (EphA5) expression and its clinicopathological significance in gastric cancer. Gastric cancer tissues were analyzed by immunohistochemistry. The association between EphA5 expression and clinicopathological parameters, human epidermal growth factor receptor 2 (HER2) status and Ki-67 proliferation index was statistically analyzed. EphA5 expression was detected in all non-tumor gastric epithelia but was differentially expressed among gastric cancer samples. EphA5 was negatively expressed in 30/110 (27.3%) and positively expressed in 80/110 (72.3%) samples from patients with gastric cancer. EphA5 expression was significantly associated with Lauren classification (P=0.032), lymph node metastasis (P<0.001), HER2 expression (P=0.020) and Ki-67 expression (P=0.005). No significant association was determined between EphA5 expression and age, sex, primary location, depth of invasion and Tumor-Node-Metastasis stage. The present data indicated that EphA5 is differentially expressed in gastric cancer. EphA5 may therefore be a potential therapeutic target and may have clinical utility as a marker for lymph node metastasis in gastric cancer.

Validated clinico-pathologic nomogram in the prediction of HER2 status in gastro-oesophageal cancer

Background

HER2 is the only validated predictive biomarker in gastro-oesophageal carcinoma (GOC). However, several factors, such as heterogeneity in protein expression, shortage of evaluable tumour tissue and need for quick target assessment, underline the usefulness of a pre-screening tool in order to anticipate HER2 status.

Methods

Data from 723 consecutive GOC analysed for HER2 at four Italian Institutions were collected. HER2 positivity was defined as 3+ by immunohistochemistry (IHC) or 2+ with gene amplification by in situ hybridisation (ISH). A multivariate logistic regression model was built using data from 413 cases, whereas 310 patients served as validation cohort. C-index, visual inspection of the calibration plot, Brier score and Spiegelhalter z-test were used to assess the performance of the nomogram.

Results

HER2 positive rate was 17.4%. Four variables were retained after adjustment in the final model: grading, Lauren’s histotype, pathologic material analysed (surgical specimen/biopsy) and site of tissue collection (primary tumour/metastases). Visual inspection of the calibration plot revealed a very good overlap between predicted and observed probabilities, with a Brier score of 0.101 and a non-significant Spiegelhalter z-test (P = 0.319). C-index resulted in 0.827 (95%CI 0.741–0.913).

Conclusion

A simple nomogram based on always-available pathologic information accurately predicts the probability of HER2 positivity in GOC.

Increased Sulfiredoxin Expression in Gastric Cancer Cells May Be a Molecular Target of the Anticancer Component Diallyl Trisulfide

Sulfiredoxin (Srx) is a newly discovered antioxidant enzyme playing a role in the catalytic reduction of oxidative modifications. Srx is overexpressed in a variety of cancers. It may promote carcinogenesis as well as tumor progression. In this study, we report for the first time that Srx expression might be positively associated with the development of gastric cancer and tumor malignancy. Immunohistochemistry showed that, compared to normal tissues (42%, 20/47), Srx expression in gastric tumors (85%, 40/47) was much more common (chi-square test, p<0.01). In addition, the staining of Srx was stronger in poorly differentiated gastric cancer than in well-differentiated gastric cancer. Western blotting showed that, in the gastric tumor cell line BGC823, the Srx protein was upregulated in response to H₂O₂ treatment, although it was inadequate to counteract the increased oxidative stress, as indicated by the gradually increasing level of malondialdehyde (MDA). In addition, Srx expression, MDA levels, and ROS levels in BGC823 cells were markedly inhibited upon treatment with diallyl trisulfide (DATS), a major constituent of garlic oil with proven anticancer effects. These results suggest that Srx may be an oxidative stress marker. Antioxidation may account for the anticancer potential of garlic.

Long-term survival with stable disease after multidisciplinary treatment for synchronous liver metastases from gastric cancer: A case report

INTRODUCTION

The liver is one of the most common sites of hematogenous metastases of gastric cancer. The 5-year overall survival rate of synchronous liver metastases from gastric cancer was less than 27%. We report a rare case of patient with synchronous liver metastases from gastric cancer who experienced stable disease for 7 years and 3 months following multidisciplinary modalities.

THE PRESENTATION OF A CASE

A 33-year-old woman was admitted to our institute because of abdominal pain lasting for a day. Haemoglobin level was 68 g/L. Computed tomography (CT) scan revealed hemoperitoneum, multiple round lesions within liver parenchyma. The pathological diagnosis was gastric cancer with liver metastases. Following multidisciplinary treatment, she experienced stable disease for7 years and 3 months. Currently, the patient remains alive with no recurrence.

CONCLUSION

We report a rare case of patient with synchronous liver metastases from gastric cancer who experienced stable disease for 7 years and 3 months following multidisciplinary modalities. Future trials are required to prospectively investigate the established regimen of multidisciplinary treatment.

Advanced gastric cancer: the value of systemic and intraperitoneal chemotherapy

Several possibilities in treating advanced gastric cancer exist. Radical surgery associated with chemotherapy represents the cornerstone. Which one is more effective among neoadjuvant, adjuvant or perioperative chemotherapy is still a matter of debate. Several innovative results showed the necessity to keep increasingly into consideration the intraperitoneal administration of chemotherapies. Moreover, classical drugs and their ways of administration should be combined with the new ones to improve results. Lastly the prevention of recurrence should be considered: one possibility is to administer intraperitoneal chemotherapy earlier in the therapeutic algorithm. (www.actabiomedica.it)

Characterization of PI3KCA and BRAF mutations in gastric adenocarcinoma: An approach to a personalized targeted therapy for Moroccan HER2 overexpressed patients

BACKGROUND AND STUDY AIMS

Targeted therapies have an increasing importance in digestive oncology. To our knowledge, we are the first to report the distribution of PI3KCA and BRAF mutations in Moroccan HER2 overexpressed patients, in order to introduce targeted therapy in the arsenal of therapeutic modalities for management in Morocco.

PATIENTS AND METHODS

98 gastric adenocarcinoma tissue samples were collected. Further histological and immunohistochemical examinations were carried out at the Laboratory of Anatomy Pathology in Pasteur Institute-Morocco, in order to select HER2 positive cases. Out of 98 cases, 16 were found to be HER2-positive. The molecular study was performed for 55 good quality tissue samples including the HER2-positive ones, and activating mutations in H1047R PI3KCA and V600E BRAF were analyzed by Cast-PCR and Real-time PCR, respectively, at the Department of Molecular Biology, ANOUAL Specialized Center-Casablanca, Morocco. Statistical analyses were performed using the Epi-info software (version 6.09).

RESULTS

Pi3KCA mutation was present in 8 cases (14,54%). BRAF mutation was present in 4 cases (7,27%) and 3 cases showed concomitant mutations. In total, 9 cases (16,36%) had PI3KCA and/or BRAF mutations.

CONCLUSION

The association between HER2 expression and PI3KCA alteration in gastric adenocarcinoma is most probably necessary to identify trastuzumab responders. Consequently, the 83,64% rate of HER2-positive patients harboring wild-type mutations possibly represents the portion of patients responding to trastuzumab while the 16,36% rate of patients carrying at least one of the studied mutations represents the portion of potentially non responsive patients to the targeted therapy, and thus may be considered as good candidates for multi-drug targeted therapy.

Elevated TRIM23 expression predicts poor prognosis in Chinese gastric cancer

The gene TRIM23 (tripartite motif containing 23) is a member of the tripartite motif (TRIM) family whose expression putatively participates in many pathophysiological processes. Nonetheless, the role of TRIM23 in gastric cancer (GC) remains uncertain. Our study evaluated the expression of TRIM23 in GC tissues and cell lines, and investigated an association between TRIM23 and survival. In the present study, our results demonstrated that TRIM23 mRNA and protein were frequently over-expressed in GC cell lines and GC tissues. High level of TRIM23 protein correlated with tumor size, tumor-node-metastasis (TNM) stage, depth of invasion, lymph node metastasis (LNM), tumor differentiation, and nerve invasion. Compared with the low TRIM23 protein group, the high TRIM23 protein group was significantly associated with worse prognosis of GC patients. Consistently, the KM-plot database suggested that high TRIM23 mRNA expression was also linked to a poor prognosis in GC patients both in positive and negative subgroups of human epidermal growth factor receptor 2 (HER2). But in the HER2 positive subgroup, the advantages of the low TRIM23 expression on overall survival were much more statistically significant. The univariate analysis indicated that TRIM23 expression correlated with overall survival. The multivariate analysis showed that independent factors of prognosis in GC were lymph node metastasis, vascular invasion, and depth of invasion. In summary, TRIM23 may be associated with progression of GC, and may be considered a therapeutic target for GC patients.