Multicenter phase II study of trastuzumab in combination with capecitabine and oxaliplatin for advanced gastric cancer. Eur J Cancer. 2015;51:482-488. [PMID: 25661103 DOI: 10.1016/j.ejca.2014.12.015]

Atezolizumab and Trastuzumab Plus Chemotherapy for ERBB2-Positive Locally Advanced Resectable Gastric Cancer: A Randomized Clinical Trial

Importance

Effective treatment of locally advanced gastric cancer (GC) or gastroesophageal junction (GEJ) cancer remains a challenge.

Objective

To compare the efficacy and safety of atezolizumab plus trastuzumab plus capecitabine and oxaliplatin chemotherapy (XELOX) vs trastuzumab plus XELOX in Chinese patients with locally advanced human epidermal growth factor receptor 2 (ERBB2; formerly HER2)-positive GC or adenocarcinoma of the GEJ.

Design, Setting, and Participants

This was an open-label phase 2 randomized clinical trial conducted at 8 study sites in China. Patient recruitment started on February 25, 2021, and this study is ongoing as participants are still being actively followed up. Chinese patients eligible for surgery with locally advanced ERBB2-positive GC or adenocarcinoma of the GEJ were included. Data were analyzed from March 2021 to October 2023.

Interventions

Eligible patients were enrolled and randomly assigned 1:1 to perioperative treatment with either atezolizumab plus trastuzumab plus XELOX (arm A) or trastuzumab plus XELOX (arm B) for 3 neoadjuvant cycles (3 weeks per cycle) and 5 adjuvant cycles.

Main Outcomes and Measures

The primary efficacy end point was the pathological complete response (pCR) rate following completion of neoadjuvant therapy and surgery.

Results

In total, 42 patients were screened and randomly assigned to arm A (n = 21) or arm B (n = 21). The median (range) ages were 61 (33-72) years and 65 (49-72) years in arm A and arm B, respectively, and 39 patients (93%) were male. The pCR rate was significantly higher in arm A (8 [38%]) than arm B (3 [14%]; difference, 23.8%; 90% CI, 1.3-44.7). Age younger than 65 years, male sex, and intestinal Lauren classification were significantly associated with a better pCR rate in arm A. Median event-free survival, disease-free survival, and overall survival were not reached. Based on the same way of interpretation, major pathologic response should be statistically significantly different between the 2 arms, while other outcome measures remained not significantly different. The incidence of treatment-emergent adverse events was 100% (21 of 21) and 100% (21 of 21) in arms A and B, respectively; grade 3 or higher TEAEs, 57% (12 of 21) and 67% (14 of 21), respectively; and serious TEAEs, 29% (6 of 21) and 10% (2 of 21), respectively.

Conclusions and Relevance

In this randomized clinical trial, add-on atezolizumab to trastuzumab plus XELOX therapy demonstrated promising efficacy in this patient population, and no new safety concerns were raised.

Trial Registration

ClinicalTrials.gov Identifier: NCT04661150.

Randomized controlled phase III study comparing chemotherapy alone versus conversion surgery after a remarkable response to chemotherapy in patients with initially unresectable cStage IVB or pStage IV gastric cancer (JCOG2301, Conversion study)

The standard approach for stage IV gastric cancer is palliative chemotherapy. However, despite the advancements in various chemotherapy regimens, the prognosis remains poor, highlighting the urgent need to develop more effective treatment strategies. The controversy persists regarding the integration of a local therapy including surgery in the management of unresectable stage IV gastric cancer. This randomized phase III trial aims to confirm the additional benefit of conversion surgery following palliative chemotherapy compared with palliative chemotherapy alone with respect to overall survival in patients initially diagnosed with unresectable clinical stage IVB or pathological stage IV gastric cancer after a remarkable response to chemotherapy. This study plans to enroll 126 patients from 63 institutions in Japan for 5 years, and it has been registered in the Japan Registry of Clinical Trials as jRCTs031240340 (https://jrct.niph.go.jp/latest-detail/jRCTs031240340).

Targeting HER2 in Gastroesophageal Cancer: A New Appetite for an Old Plight

The incidence of gastroesophageal cancers is rising, driven, in part, by an increasing burden of risk factors of obesity and gastroesophageal reflux. Despite efforts to address these risk factors, and a growing interest in methods of population screening, the bulk of these tumours are unresectable at diagnosis. In this setting, effective systemic treatments are paramount to improve survival and quality of life. Early and accurate identification of oncogenic drivers, such as human epidermal growth factor receptor 2 (HER2), present in 5-30% of gastroesophageal adenocarcinomas (GEAs), is integral to guide choice of therapies due to the clear predictive implications that arise from overexpression of this receptor. After trastuzumab, the first anti-HER2 agent with approved use in HER2-positive GEA, the addition of pembrolizumab to first-line trastuzumab-chemotherapy and trastuzumab deruxtecan in the refractory space have more recently changed practice. Yet, the response to these agents has been vastly different across patients with HER2-positive disease, underpinning the need for reliable biomarkers of response. Emergent data have suggested that levels of HER2 expression on tissue or liquid biopsies may predict response to first-generation HER2 therapies while HER2 heterogeneity, receptor changes, co-occurring molecular alterations and oncogenic genomic and metabolic reprogramming may be implicated in resistance. A robust knowledge of the mechanisms of resistance and response to HER2-directed therapies is necessary to inform novel strategies of HER2-targeting and guide choice combinations with other biomarker-directed therapies, to improve outcomes from a new generation of clinical trials in HER2-positive GEA. Understanding and close examination of previous failures in this space form an important part of this assessment, as does correlative biomarker and translational work pertaining to the role of HER2 and dynamic changes that result through treatment exposure. In this review, we aim to provide an overview of strategies for HER2 targeting, summarising both the successes and disappointments in this therapeutic landscape and discuss existing challenges and future perspectives on development in this highly morbid tumour type.

A Comprehensive and Comparative Review of Global Gastric Cancer Treatment Guidelines: 2024 Update

Differences in demographics, medical expertise, and patient healthcare resources across countries have led to significant variations in guidelines. In light of these differences, in this review, we aimed to explore and compare the most recent updates to gastric cancer treatment from five guidelines that are available in English. These English-version guidelines, which have been recently published and updated for journal publication, include those published in South Korea in 2024, Japan in 2021, China in 2023, the United States in 2024, and Europe in 2024. The South Korean and Japanese guidelines provide a higher proportion of content to endoscopic and surgical treatments, reflecting their focus on minimally invasive techniques, function-preserving surgeries, and systemic therapy. The Chinese guidelines provide recommendations addressing not only surgical approaches but also perioperative chemotherapy and palliative systemic therapy. Meanwhile, in the United States and European guidelines, a higher proportion of the content is dedicated to perioperative and palliative systemic therapy, aligning with their approaches to advanced-stage disease management. All guidelines address surgical and systemic chemotherapy treatments; however, the proportion and emphasis of content vary based on the patient distribution and treatment approaches specific to each country. With emerging research findings on gastric cancer treatment worldwide, the national guidelines are being progressively revised and updated. Understanding the commonalities and differences among national guidelines, along with the underlying evidence, can provide valuable insights into the treatment of gastric cancer.

Prospective single-arm multicenter interventional study of surgical resection for liver metastasis from gastric cancer; 3-year overall and recurrence-free survival

OBJECTIVE

Potential benefit of surgical resection for liver metastasis from gastric cancer (LMGC) remains controversial because most previous studies were retrospective. We evaluated the outcomes of surgical resection following chemotherapy for LMGC in a prospective single-arm multicenter interventional study.

METHODS

Patients with synchronous or metachronous LMGC received 2-4 cycles of standard chemotherapy and proceeded to surgical resection if restaging showed a non-progressive disease with a chance of R0 resection. The primary endpoint was 3-year OS of R0 patients, with RFS as secondary. Prognostic factors for R0 patients were evaluated by multivariable Cox regression analysis.

RESULTS

Seventy patients were enrolled between 2011 and 2019. Two patients were ineligible, and 20 discontinued treatment before surgery. Of the 48 patients eventually undergoing surgery, 43 accomplished R0 resection of the primary and/or metastatic GC, while 1 ended in R2 resection and 4 were considered ineligible. Median and 3-year OS for R0 patients were 39.8 months (95 % confidence interval [CI], 26.9 to not reached) and 58.1 % (95 % CI, 43.1-71.8), respectively, while median and 3-year RFS were 14.9 months (95 % CI 7.9-34.0) and 34.9 % (95 % CI 22.2-50.1), respectively. On multivariable analysis, both multiple liver metastases and positive nodal status (pN1-3) were negatively associated with OS (multiple liver metastases: hazard ratio [HR] 2.71 (95 % CI, 1.16-6.35), P = 0.022; pN1-3: HR 9.11 (95 % CI, 1.22-68.2), P = 0.031).

CONCLUSION

R0 resection following chemotherapy for LMGC yielded promising survival, with multiple liver metastases and positive nodal status being significant indicators of poor prognosis.

CLINICAL TRIAL REGISTRATION NUMBER

UMIN 000011445 (https://www.umin.ac.jp/ctr/).

Impact of oxaliplatin and trastuzumab combination therapy on tumor markers and T lymphocyte subsets for advanced gastric cancer

BACKGROUND

Advanced gastric cancer (AGC) remains a challenging malignancy with poor prognosis. The combination of oxaliplatin and trastuzumab has shown promising results in AGC treatment. This study aimed to investigate the effects of oxaliplatin and trastuzumab combination therapy on serum tumor markers and T lymphocyte subsets in patients with AGC and to explore their potential as predictive biomarkers for treatment response.

AIM

To investigate the impact of oxaliplatin and trastuzumab combination therapy on serum markers and T cell subsets in patients with AGC.

METHODS

This prospective study enrolled 60 patients with AGC. All patients received oxaliplatin (130 mg/m2, every 3 weeks) and trastuzumab (8 mg/kg loading dose, followed by 6 mg/kg every 3 weeks) for six cycles. Serum carcinoembryonic antigen (CEA), cancer antigen 19-9 (CA19-9), and cancer antigen 72-4 (CA72-4) were measured before and after treatment. T-lymphocyte subsets, including CD3+, CD4+, CD8+, and CD4+ /CD8+ ratios, were also evaluated. The clinical response was assessed using the Response Evaluation Criteria in Solid Tumors version 1.1.

RESULTS

After six cycles of treatment, the CEA, CA19-9, and CA72-4 serum levels significantly decreased compared to baseline levels (P < 0.001). The percentages of CD3+ and CD4+ T lymphocytes increased significantly (P < 0.05), whereas the percentage of CD8+ T lymphocytes decreased (P < 0.05). The CD4+/CD8+ ratio also significantly increased after treatment (P < 0.05). Patients with a higher decrease in serum tumor markers (≥ 50% reduction) and a higher increase in CD4+/CD8+ ratio (≥ 1.5-fold) showed better clinical response rates (P < 0.05).

CONCLUSION

Oxaliplatin and trastuzumab combination therapy effectively reduced serum tumor marker levels and modulated T lymphocyte subsets in patients with AGC. Combination therapy not only has a direct antitumor effect, but also enhances the immune response in patients with AGC. Serum tumor markers and T lymphocyte subsets may serve as potential predictive biomarkers for treatment response in patients with AGC receiving combination therapy.

Advances in the treatment of human epidermal growth factor receptor 2-positive gastric cancer

Human epidermal growth factor receptor 2 has been a pivotal biomarker for gastric cancer treatment strategies for many years. However, more than a decade after the ToGA trial demonstrated the efficacy of trastuzumab in improving survival, the development of treatments targeting human epidermal growth factor receptor 2 remains challenging. Several large-scale clinical trials of tyrosine kinase inhibitors, non-trastuzumab anti-human epidermal growth factor receptor 2 antibodies, and antibody-drug conjugates have failed to meet the primary endpoints. The concept of trastuzumab beyond progression and the complexity of resistance mechanisms to anti-human epidermal growth factor receptor 2 therapy after trastuzumab treatment presented significant obstacles, leading to trastuzumab being the sole therapy for human epidermal growth factor receptor 2-positive gastric cancer for some time. Nevertheless, the landscape has shifted in recent years, especially since the introduction of the antibody-drug conjugate trastuzumab deruxtecan in 2020. This has rekindled the interest in developing treatments targeting human epidermal growth factor receptor 2 in gastric cancer.

Biomarker-oriented chemo-immunotherapy for advanced gastric cancer

The biomarker-oriented chemo-immunotherapy is useful and promising in the development of new anticancer agents, since the responders can be enriched by selecting patients with biomarkers. Compared to colorectal and lung cancers, the development of biomarker-driven molecular-targeted therapeutics for gastric cancers has been straggled. However, several new biomarkers in gastric cancers have been discovered and clinical trials in enrichment design with certain biomarkers have been conducted. Therefore, there are currently several treatment options to treat gastric cancer patients based on individual biomarker-oriented strategies. In the present review, we describe the useful biomarkers in gastric cancer, with focusing on HER2, PD-L1, and Claudin18.2, in relation to their clinical significance and associated targeted agents.

Chinese Medicine Prolongs Overall Survival of Chinese Patients with Advanced Gastric Cancer: Treatment Pattern and Survival Analysis of a 20-Year Real-World Study

OBJECTIVE

To describe the treatment patterns and survival status of advanced gastric cancer (AGC) in China in the past two decades, and objectively evaluate the impact of standardized Chinese medicine (CM) treatment on the survival of AGC patients.

METHODS

This multicenter registry designed and propensity score analysis study described the diagnosis characteristics, treatment-pattern development and survival status of AGC from 10 hospitals in China between January 1, 2000 and July 31, 2021. Overall survival (OS) was evaluated between non-CM cohort (standard medical treatment) and CM cohort (integrated standard CM treatment ≥3 months). Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were performed to adjust any difference in average outcomes for bias.

RESULTS

A total of 2,001 patients histologically confirmed locally advanced and/or metastasis stomach and gastroesophageal junction adenocarcinoma were enrolled. Among them, 1,607 received systemic chemotherapy, 215 (10.74%) accepted molecular targeted therapy, 44 (2.2%) received checkpoint inhibitor therapy, and 769 (38.43%) received CM. Two-drug regimen was the main choice for first-line treatment, with fluoropyrimidine plus platinum as the most common regimen (530 cases, 60.09%). While 45.71% (16 cases) of patients with HER2 amplification received trastuzumab in first-line. The application of apatinib increased (33.33%) in third-line. The application of checkpoint inhibitors has increased since 2020. COX analysis showed that Lauren mixed type (P=0.017), cycles of first-line treatment >6 (P=0.000), CM (P=0.000), palliative gastrectomy (P=0.000), trastuzumab (P=0.011), and apatinib (P=0.008) were independent prognostic factors for the OS of AGC. After PSM and IPTW, the median OS of CM cohort and non-CM cohort was 18.17 and 12.45 months, respectively (P<0.001).

CONCLUSIONS

In real-world practice for AGC in China, therapy choices consisted with guidelines. Two-drug regimen was the main first-line choice. Standardized CM treatment was an independent prognostic factor and could prolong the OS of Chinese patients with AGC. (Registration No. NCT02781285).

German, Austrian, and Swiss guidelines for systemic treatment of gastric cancer

The updated edition of the German, Austrian and Swiss Guidelines for Systemic Treatment of Gastric Cancer was completed in August 2023, incorporating new evidence that emerged after publication of the previous edition. It consists of a text-based "Diagnosis" part and a "Therapy" part including recommendations and treatment algorithms. The treatment part includes a comprehensive description regarding perioperative and palliative systemic therapy for gastric cancer and summarizes recommended standard of care for surgery and endoscopic resection. The guidelines are based on a literature search and evaluation by a multidisciplinary panel of experts nominated by the hematology and oncology scientific societies of the three involved countries.

Preventive effect of dexamethasone premedication on the development of infusion-related reaction in breast cancer patients receiving trastuzumab

AIM

To clarify the incidence and risk factors of infusion-related reactions (IRRs) caused by trastuzumab in breast cancer patients and verify the preventive effects of dexamethasone.

METHODS

All breast cancer patients newly treated with trastuzumab at the Osaka Medical and Pharmaceutical University Hospital from 1 January 2017 to 31 December 2020 were included. The electronic medical records were retrospectively reviewed. The outcome measure was the occurrence of IRRs of grade 1 or higher during trastuzumab infusion. Only dexamethasone and anticancer drugs administered concomitantly before trastuzumab were used as explanatory variables.

RESULTS

The 176 patients included in the study received 2320 infusions. Fifty-eight patients (33.0%) experienced IRRs, and IRRs occurred in 80 (3.4%) of the total 2320 infusions. Owing to the hierarchical structure of the data, the independence of the observed values was evaluated using the intraclass correlation coefficient. Multivariate multilevel logistic regression analysis showed that premedication with dexamethasone lowered the risk of trastuzumab-induced IRRs (mg, per 1 unit, odds ratio [OR] = 0.61, 95% confidence interval [95% CI] 0.43-0.85, P = .003). In addition, preoperative status (OR = 38.9, 95% CI 5.4-278.7, P < .001) and high-dose trastuzumab (mg/kg, per 1 unit, OR = 60.6, 95% CI 20.1-182.9, P < .001) were independent risk factors for IRRs.

CONCLUSION

The results of this study suggest that premedication with dexamethasone exhibits preventive effects on trastuzumab-induced IRRs in breast cancer patients. Future studies are needed to determine the optimal dose of dexamethasone to prevent IRRs and the impact of dexamethasone on the efficacy of trastuzumab in breast cancer.

Optimal treatment strategy after first-line induction therapy in advanced HER2-positive oeso-gastric adenocarcinoma-a retrospective, international, multicentric AGEO study

BACKGROUND

The optimal treatment strategy after first-line induction therapy in advanced HER2-positive oeso-gastric adenocarcinoma (OGA) remains challenging.

METHODS

Patients treated with trastuzumab (T) plus platinum salts and fluoropyrimidine (F) as first-line chemotherapy between 2010 and 2020 for HER2-positive advanced OGA at 17 academic care centers in France, Italy, and Austria were included. The primary objective was the comparison of F + T vs T alone as maintenance regimen in terms of progression-free survival (PFS) and overall survival (OS) after a platinum-based chemotherapy induction + T. As secondary objective, PFS and OS between patients treated with reintroduction of initial chemotherapy or standard second-line chemotherapy at progression were assessed.

RESULTS

Among the 157 patients included, 86 (55%) received F + T and 71 (45%) T alone as a maintenance regimen after a median of 4 months of induction chemotherapy. Median PFS from start of maintenance therapy was 5.1 months in both groups (95% CI 4.2-7.7 for F + T and 95% CI 3.7-7.5 for T alone; p = 0.60) and median OS was 15.2 (95% CI 10.9-19.1) and 17.0 months (95% CI 15.5-21.6) for F + T and T alone, respectively (p = 0.40). Of 112/157 patients (71%) receiving systemic therapy after progression under maintenance, 26/112 (23%) were treated with a reintroduction of initial chemotherapy + T and 86/112 (77%) with a standard second-line regimen. Here, median OS was significantly longer with the reintroduction (13.8 (95% CI 12.1-19.9) vs 9.0 months (95% CI 7.1-11.9); p = 0.007) as confirmed by multivariate analysis (HR 0.49; 95% CI 0.28-0.85; p = 0.01).

CONCLUSION

No additional benefit of adding F to T monotherapy as a maintenance treatment could be observed. Reintroduction of initial therapy at first progression may be a feasible approach to preserve later treatment lines.

Response prediction in patients with gastric and esophagogastric adenocarcinoma under neoadjuvant chemotherapy using targeted gene expression analysis and next-generation sequencing in pre-therapeutic biopsies

OBJECTIVES

Perioperative chemo-(radio-) therapy is the accepted standard in European patients with locally advanced adenocarcinoma of the esophagogastric junction or stomach (AEG/AS). However, 30-85% of patients do not respond to this treatment. The aim of our study was the identification of predictive biomarkers in pre-therapeutic endoscopic tumor biopsies from patients with histopathologic response (Becker-1) versus non-response (Becker-2/3) to preoperative chemotherapy.

METHODS

Formalin-fixed paraffin-embedded biopsies from 36 Caucasian patients (Becker-1 n = 11, Becker-2 n = 7, Becker-3 n = 18) with AEG/AS, taken prior to neoadjuvant chemotherapy were selected. For RNA expression analysis, we employed the NanoString nCounter System. To identify genomic alterations like single nucleotide variants (SNV), copy number variation (CNV) and fusion events, we used Illumina TST170 gene panel. For HER2 and FGFR2 protein expression, immunostaining was performed. Furthermore, we analyzed the microsatellite instability (MSI) and Epstein-Barr virus (EBV) infection status by EBER in situ hybridization.

RESULTS

Heat map and principal component analyses showed no clustering by means of gene expression according to regression grade. Concerning two recently proposed predictive markers, our data showed equal distribution for MSI (Becker-1: 2; Becker-2: 1; Becker-3: 3; out of 29 tested) and EBV infection was rare (1/32). We could not reveal discriminating target genes concerning SNV, but found a higher mutational burden in non-responders versus responders and fusion (in 6/14) and CNV events (in 5/14) exclusively in Becker-3.

CONCLUSIONS

Although we could not identify discriminating target genes, our data suggest that molecular alterations are in general more prevalent in patients with AEG/AS belonging to the non-responding Becker group 3.

Breakthroughs in the Systemic Treatment of HER2-Positive Advanced/Metastatic Gastric Cancer: From Singlet Chemotherapy to Triple Combination

Gastric cancer is heterogeneous in morphology, biology, genomics, and treatment response. Alterations in human epidermal growth factor receptor 2 (HER2) overexpression, microsatellite instability (MSI) status, programmed death-ligand 1 (PD-L1) levels, and fibroblast growth factor receptor 2 (FGFR2) can be used as biomarkers. Since the combination of fluoropyrimidine/platinum plus trastuzumab that was investigated in the ToGA trial was approved as a standard of care in HER2-positive patients in 2010, no other agents showed efficacy in the first- (HELOISE, LOGiC, JACOB trials) and second- (TyTAN, GATSBY, T-ACT trials) line treatments. Despite the success in treating breast cancer, various anti-HER2 agents, including a monoclonal antibody (pertuzumab), an antibody-drug conjugate (ADC; trastuzumab emtansine [T-DM1]), and a small molecule (lapatinib) failed to translate into clinical benefits until the KEYNOTE-811 (first-line) and DESTINY-Gastri01 (≥second-line) trials were conducted. The incorporation of HER2-directed treatment with immune checkpoint inhibitors in the form of a monoclonal antibody or ADC is now approved as a standard treatment. Despite the promising results of new agents (engineered monoclonal antibodies, bi-specific antibodies, fusion proteins, and small molecules) in the early phase of development, the management of HER2-positive gastric cancer requires further optimization to achieve precision medicine with a chemotherapeutic backbone. Treatment resistance is a complex process that can be overcome using a combination of chemotherapy, targeted agents, and immune checkpoint inhibitors, including novel agents. HER2 status must be reassessed in patients undergoing anti-HER2 treatment with disease progression after the first-line treatment. As a general guideline, patients who need systemic treatment should receive chemotherapy plus targeted agents, anti-angiogenic agents, immune checkpoint inhibitors, or their combinations.

Japanese Gastric Cancer Association. Japanese Gastric Cancer Treatment Guidelines 2021 (6th edition)

The sixth edition of the Japanese Gastric Cancer Treatment Guidelines was completed in July 2021, incorporating new evidence that emerged after publication of the previous edition. It consists of a text-based "Treatments" part and a "Clinical Questions" part including recommendations and explanations for clinical questions. The treatments parts include a comprehensive description regarding surgery, endoscopic resection and chemotherapy for gastric cancer. The clinical question part is based on the literature search and evaluation by an independent systematic review team. Consequently, not only evidence for each therapeutic recommendation was clearly shown, but it also identified the research fields that require further evaluation to provide appropriate recommendations.

Recent Trends and Advancements in the Diagnosis and Management of Gastric Cancer

Gastric cancer is an enigmatic malignancy that has recently been shown to be increasing in incidence globally. There has been recent progress in emerging technologies for the diagnosis and treatment of the disease. Improvements in non-invasive diagnostic techniques with serological tests and biomarkers have led to decreased use of invasive procedures such as endoscopy. A multidisciplinary approach is used to treat gastric cancer, with recent significant advancements in systemic therapies used in combination with cytotoxic chemotherapies. New therapeutic targets have been identified and clinical trials are taking place to assess their efficacy and safety. In this review, we provide an overview of the current and emerging treatment strategies and diagnostic techniques for gastric cancer.

Targeting HER2 in metastatic gastroesophageal adenocarcinomas: What is new?

Gastric and esophageal adenocarcinomas represent a biologically heterogeneous disease. The identification, in early eighties, of human epidermal growth factor receptor 2 (HER2) overexpression, being present in 12 to 20% of the cases, marked a major milestone in the efforts of unraveling the molecular complexity of this disease. This led to the development of anti-HER2-therapies, trastuzumab being the first to demonstrate, in combination with cisplatin and 5FU/capecitabine chemotherapy, an improvement in response rate and survival in the first-line setting of patients with metastatic, HER2-positive gastroesophageal adenocarcinomas. Afterwards, during a decade, several studies have tried new strategies either to block HER2 pathway differently or to combine different anti-HER2, without efficacy. Everything changed with studies demonstrating additive effect between anti-HER2 and immune checkpoint inhibitors and leading to phase III clinical trials combining anti-HER2 and anti-PD-L1/PD1 therapies. Pembrolizumab, a PD-1 inhibitor, was recently granted by FDA an accelerated approval, in patients with HER2-positive gastro-oesophageal adenocarcinomas, in combination with trastuzumab and platinum-based chemotherapy following meaningful improvement in overall response rate over standard treatment. Progression-free and overall-survival results are still awaited to change our first-line standard treatment. Furthermore, new HER2 inhibitors have been developed, blocking HER2-mediated pathway signaling via different mechanisms from pan-HER inhibition to anti-HER2 antibody drug conjugates with promising results in pretreated patients. Trastuzumab-deruxtecan has in particular showed interesting results in pretreated patients. We present here a review of the recent data and perspectives in HER2-positive metastatic gastroesophageal adenocarcinomas.

Proteomic characterization of gastric cancer response to chemotherapy and targeted therapy reveals new therapeutic strategies

Chemotherapy and targeted therapy are the major treatments for gastric cancer (GC), but drug resistance limits its effectiveness. Here, we profile the proteome of 206 tumor tissues from patients with GC undergoing either chemotherapy or anti-HER2-based therapy. Proteome-based classification reveals four subtypes (G-I-G-IV) related to different clinical and molecular features. MSI-sig high GC patients benefit from docetaxel combination treatment, accompanied by anticancer immune response. Further study reveals patients with high T cell receptor signaling respond to anti-HER2-based therapy; while activation of extracellular matrix/PI3K-AKT pathway impair anti-tumor effect of trastuzumab. We observe CTSE functions as a cell intrinsic enhancer of chemosensitivity of docetaxel, whereas TKTL1 functions as an attenuator. Finally, we develop prognostic models with high accuracy to predict therapeutic response, further validated in an independent validation cohort. This study provides a rich resource for investigating the mechanisms and indicators of chemotherapy and targeted therapy in GC.

From Anti-HER-2 to Anti-HER-2-CAR-T Cells: An Evolutionary Immunotherapy Approach for Gastric Cancer

Current Therapeutic modalities provide no survival advantage to gastric cancer (GC) patients. Targeting the human epidermal growth factor receptor-2 (HER-2) is a viable therapeutic strategy against advanced HER-2 positive GC. Antibody-drug conjugates, small-molecule tyrosine kinase inhibitors (TKIs), and bispecific antibodies are emerging as novel drug forms that may abrogate the resistance to HER-2-specific drugs and monoclonal antibodies. Chimeric antigen receptor-modified T cells (CAR-T) targeting HER-2 have shown considerable therapeutic potential in GC and other solid tumors. However, due to the high heterogeneity along with the complex tumor microenvironment (TME) of GC that often leads to immune escape, the immunological treatment of GC still faces many challenges. Here, we reviewed and discussed the current progress in the research of anti-HER-2-CAR-T cell immunotherapy against GC.

Trastuzumab ± Capecitabine Maintenance After the First-Line Treatment of HER2-Positive Advanced Gastric Cancer: Retrospective Observational Real-Life Data of Turkish Oncology Group

PURPOSE

In the ToGA trial for HER2-positive advanced gastric cancer, cisplatin plus fluoropyrimidine was given for 6 cycles; trastuzumab was given until disease progression. However, there is a lack of real-life data about trastuzumab maintenance after 6 cycle chemotherapy. This study aims to present real-life data of trastuzumab ± capecitabine maintenance after 6 cycles of platinum, fluoropyrimidine, and trastuzumab in non-progressive patients.

METHODS

This is a retrospective multicenter study of the Turkish Oncology Group. A total of 35 HER2-positive, inoperable locally advanced, recurrent, or metastatic gastric adenocarcinoma patients being non-progressive at the end of 6 cycle chemotherapy and being given trastuzumab ± capecitabine as maintenance treatment were included from sixteen oncology centers. Baseline characteristics, objective tumor responses, progression free and overall survival data, and toxicities were determined.

RESULTS

About 68% of the patients were given CF, and 32% were given FOLFOX with trastuzumab as the first-line treatment. The best response in 6 cycle chemotherapy was complete 8 (22%), partial 24 (68%), and stable disease 3 (8%). All patients had trastuzumab maintenance (median cycle 13; range 7-51), and 49% of the patients had capecitabine with trastuzumab (median capecitabine cycle 6; range 2-30). The median PFS of the patients was 12.0 months (95% CI 10.3-13.7), and median OS was 17.4 months (95% CI 15.2-19.5). There were 2 patients with grade 1 cardiotoxicity.

CONCLUSION

Trastuzumab maintenance ± capecitabine after 6 cycles of trastuzumab plus combined chemotherapy treatment revealed efficacy and safety in non-progressive HER2-positive advanced gastric cancer.

Current status and future perspectives in HER2 positive advanced gastric cancer

Gastric cancer is one of the most common malignancy worldwide with a prognosis less than 1 year in unresectable or metastatic disease. HER2 expression is the main biomarker to lead the addition of trastuzumab to first line systemic chemotherapy improving the overall survival in advanced HER2-positivegastric adenocarcinoma. The inevitable development of resistance to trastuzumab remains a great problem inasmuch several treatment strategies that have proven effective in breast cancer failed to show clinical benefit in advanced gastric cancer. In this review, we summarize the available data on the mechanisms underlying primary and secondary resistance toHER2-targeted therapy and current challenges in the treatment of HER2-positive advanced gastric cancer refractory to trastuzumab. Further, we describe the prognostic value of new non-invasive screening techniques, the current development of novel agents such us HER2 antibody-drug conjugates and bispecific antibodies, and the strategies with antitumor activity on going.

Safety and efficacy of HER2 blockade by trastuzumab-based chemotherapy-containing combination strategies in HER2+ gastroesophageal adenocarcinoma

Since completion of the Trastuzumab for Gastric Cancer study, trastuzumab with doublet chemotherapy (a fluoropyrimidine and a platinum) has been the gold-standard first-line therapy for patients with locally advanced unresectable or metastatic human epidermal growth factor receptor 2-positive (HER2+) gastroesophageal adenocarcinoma (GEA). The safety and efficacy of 23 studies of first-line trastuzumab plus doublet chemotherapy, without checkpoint inhibitors (n = 19) or with checkpoint inhibitors (n = 4), conducted in patients with locally advanced unresectable or metastatic HER2+ GEA, including phase II/III, prospective, and retrospective observational studies, were summarized. In studies without checkpoint inhibitors, the median duration of trastuzumab treatment ranged from 19.5 to 39.0 weeks and from 15.3 to 30.0 weeks for chemotherapy. In studies with checkpoint inhibitors, the median duration of pembrolizumab/trastuzumab/chemotherapy was 30 weeks, and 18 weeks for chemotherapy. In studies without checkpoint inhibitors, treatment-emergent adverse events (TEAEs) of grade ≥3 ranged from 32% to 84%. Serious adverse events (SAEs) ranged from 15% to 39%. Adverse events resulting in discontinuation ranged from 0% to 30%. Treatment-related deaths occurred in 0%-9% of patients. In studies with checkpoint inhibitors, TEAEs of grade ≥3 were 57%. SAEs ranged from 31% to 38%. Adverse events resulting in discontinuation ranged from 5% to 24%. Treatment-related deaths occurred in 0%-3% of patients. In studies without checkpoint inhibitors, objective response rate (ORR) ranged from 39% to 82%, median progression-free survival (PFS) from 5.7 to 11.6 months, and median overall survival (OS) from 11.2 to 27.6 months. In studies with checkpoint inhibitors, ORR ranged from 39% to 86%, median PFS from 8.0 to 13.0 months, and median OS from 19.3 to 27.3 months. This review provides a historical benchmark on safety and efficacy of available first-line chemotherapy-based standard of care for patients with locally advanced unresectable or metastatic HER2+ GEA.

Prospective Multicenter Interventional Study of Surgical Resection for Liver Metastasis from Gastric Cancer: R0 Resection Rate, and Operative Morbidity and Mortality

BACKGROUND

The optimal treatment for liver metastasis from gastric cancer (LMGC) remains uncertain. The relevance of surgical resection is controversial. We conducted a prospective multicenter interventional study of surgical resection for LMGC.

PATIENTS AND METHODS

Patients with synchronous or metachronous LMGC who were surgically fit were registered. The primary endpoint was 3-year overall survival (OS) of patients who underwent R0 resection. Secondary endpoints were R0 resection rate, operative morbidity and mortality, 3-year recurrence-free survival (RFS) of R0 patients, and OS in all registered patients.

RESULTS

Seventy patients were registered from 24 institutions between December 2011 and November 2019 and received preoperative chemotherapy. Three patients were ineligible, and 19 patients discontinued treatment, with disease progression in 12, adverse events in 4, and consent withdrawal in 3 before surgery. Of the 48 patients eventually undergoing surgery, R0 resection of the primary and/or metastatic GC was accomplished in 43 patients, while 1 patient discontinued treatment for positive peritoneal lavage cytology and 4 patients were considered ineligible based on postoperative pathological findings other than GC. The R0 resection rate of all eligible patients was 68.3% [95% confidence interval (CI) 55.3-79.4%, 43/63 patients], while that of all resected patients was 89.6% (95% CI 77.3-96.5%, 43/48 patients). Postoperative complications were identified in 12 out of 43 patients (27.9%), and Clavien-Dindo grade III or higher complications occurred in seven patients (16.3%). No hospital mortality was observed.

CONCLUSIONS

R0 resection for LMGC could be performed in approximately two-thirds of all eligible patients, with acceptable surgical morbidity and mortality.

A Comprehensive and Comparative Review of Global Gastric Cancer Treatment Guidelines

Countries differ in their treatment expertise and research results regarding gastric cancer; hence, treatment guidelines are diverse based on evidence and medical situations. A comprehensive and comparative review of each country’s guidelines is imperative to understand the similarities and differences among countries. We reviewed and compared five gastric cancer treatment guidelines in terms of endoscopic, surgical, perioperative, and palliative systemic treatment based on evidence levels and recommendation grades, as well as the postoperative follow-up strategies for each guideline. The Korean, Chinese, and European guidelines provided evidence and grading of the recommendations. The United States guidelines suggested categories for evidence and consensus. The Japanese guidelines suggested evidence and recommendations only for systemic treatment. The Korean and Japanese guidelines described endoscopic treatment, surgery, and lymphadenectomy in detail. The Chinese, United States, and European guidelines more intensively considered perioperative chemotherapy. In particular, the indications for chemotherapy and the regimens recommended by each guideline differed slightly. Considering their medical situations, each guideline had some diversity in terms of adopting evidence, which resulted in heterogeneous recommendations. This review will help medical personnel to comprehensively understand the diversity in gastric cancer treatment guidelines for each country in terms of evidence and recommendations.

Novel Biomarkers of Gastric Adenocarcinoma: Current Research and Future Perspectives

Simple Summary

Gastric cancer is characterized by poor survival rates despite surgery and chemotherapy. Current research focuses on biomarkers to improve diagnosis and prognosis, and to enable targeted treatment strategies. The aim of our review was to give an overview over the wide range of novel biomarkers in gastric cancer. These biomarkers are targets of a specific treatment, such as antibodies against human epidermal growth factor receptor 2. Other promising biomarkers for targeted therapies that have shown relevance in clinical trials are vascular endothelial growth factor, programmed cell death protein 1, and Claudin 18.2. There is a vast number of biomarkers based on DNA, RNA, and protein expression, as well as detection of circulating tumor cells and the immune tumor microenvironment.

Abstract

Overall survival of gastric cancer remains low, as patients are often diagnosed with advanced stage disease. In this review, we give an overview of current research on biomarkers in gastric cancer and their implementation in treatment strategies. The HER2-targeting trastuzumab is the first molecular targeted agent approved for gastric cancer treatment. Other promising biomarkers for targeted therapies that have shown relevance in clinical trials are VEGF and Claudin 18.2. Expression of MET has been shown to be a negative prognostic factor in gastric cancer. Targeting the PD-1/PD-L1 pathway with immune checkpoint inhibitors has proven efficacy in advanced gastric cancer. Recent technology advances allow the detection of circulating tumor cells that may be used as diagnostic and prognostic indicators and for therapy monitoring in gastric cancer patients. Prognostic molecular subtypes of gastric cancer have been identified using genomic data. In addition, transcriptome profiling has allowed a comprehensive characterization of the immune and stromal microenvironment in gastric cancer and development of novel risk scores. These prognostic and predictive markers highlight the rapidly evolving field of research in gastric cancer, promising improved treatment stratification and identification of molecular targets for individualized treatment in gastric cancer.

Efficacy of trastuzumab and potential risk factors on survival in patients with HER2-positive metastatic gastric cancer

Aim: To evaluate the efficacy of trastuzumab and potential risk factors on survival in patients with HER2-positive metastatic gastric cancer. Methods: We retrospectively included 138 patients who were given trastuzumab-based chemotherapy as first-line treatment and analyzed the relationship between clinical response rates and maintenance treatment status and survival outcomes. Results: In the whole group, the median progression-free survival and overall survival were 10.2 and 16 months, respectively. Clinical response was obtained in 79% of patients. The median overall survival was 16.9 months in follow-up group and 19.0 months in the maintenance group in patients with clinical response. Continuation of maintenance trastuzumab created a significant survival advantage (p = 0.021). Eastern Cooperative Oncology Group performance status 2 (hazard ratio [HR]: 2.02), grade 3 (HR: 1.78) and more than four metastatic lesions (HR: 1.67) were determined as risk factors for death. Conclusion: We recommend the continuation of maintenance trastuzumab in patients with clinical response, but those with identified risk factors may not benefit from treatment because life expectancy may be low.

Toward a Treatment Sequencing Strategy: A Systematic Review of Treatment Regimens in Advanced Gastric Cancer/Gastroesophageal Junction Adenocarcinoma

BACKGROUND

Platinum and fluoropyrimidine combinations typically comprise first-line (1L) therapy in advanced gastric cancer or gastroesophageal junction adenocarcinoma (G/GEA), although controversy exists regarding the use of 5doublet versus triplet cytotoxic regimens. Historically, second-line (2L) and third-line or later (3L+) therapy has been fragmented. Recent trials have increased the need for optimal treatment sequencing in advanced G/GEA.

MATERIALS AND METHODS

We conducted a systematic search of peer-reviewed manuscripts of randomized clinical trials examining 1L, 2L, and 3L+ therapy for advanced G/GEA published from 2009 through November 19, 2019. When available, overall survival, progression-free survival, time to progression, overall response rate, and toxicity were extracted from each and compared descriptively.

RESULTS

In 1L therapy, chemotherapy triplets demonstrated variable efficacy improvements with invariable increased toxicity compared with platinum/fluoropyrimidine doublets. Currently, the only published report of positive outcomes using biologics in 1L describes adding trastuzumab in HER2-overexpressing advanced G/GEA. In 2L, doublet chemotherapy regimens are not uniformly more efficacious than single-agent taxanes or irinotecan, and ramucirumab has demonstrated improved outcomes both as monotherapy and in combination.

CONCLUSION

For advanced G/GEA, review of trial results from 2009-2019 support 1L therapy with platinum and fluoropyrimidine and sequencing with taxanes or irinotecan in combination with biologics as effective 2L options. Escalating to a triplet may add some efficacy at the expense of added toxicity.

IMPLICATIONS FOR PRACTICE

The rapidly changing treatment landscape for advanced gastric cancer includes increasing options for refractory disease. With multiple first-line platinum-based regimens, identification of those with the best benefit-to-risk ratio may provide guidance on treatment sequencing strategies. This article presents findings from the published literature of randomized controlled trials that included a first-line platinum/fluoropyrimidine combination and, for second-line trials, patients with platinum/fluoropyrimidine-refractory disease. This guiding summary could be a tool for clinicians to identify the optimal first-line regimen(s) followed by a strategy for subsequent regimens.

Combination of trastuzumab and taxane-containing intensified chemotherapy in first-line treatment of HER2-positive advanced gastric cancer

PURPOSE

Taxane-containing combinations are recommended for the first-line therapy of advanced gastric cancer. It is not known which chemotherapy regimen is the best with trastuzumab for HER2-positive patients. The aim of this study was to compare taxane-containing intensified chemotherapy versus standard chemotherapy in combination with trastuzumab in the first-line treatment of HER2-positive advanced gastric adenocarcinoma.

METHODS

This study is a retrospective multicenter study of the Turkish Oncology Group. A total of 130 HER2-positive patients with inoperable locally advanced, recurrent, or metastatic gastric adenocarcinoma being given chemotherapy plus trastuzumab as the first-line treatment were included from 16 different oncology centers. Trastuzumab combination with intensified chemotherapy including taxane or standard chemotherapy was compared in terms of progression-free survival (PFS), overall survival (OS), and toxicity.

RESULTS

There were 108 patients in the standard and 22 patients in the intensified chemotherapy group. PFS of the standard and intensified group were 5.6 months (95% confidence interval [CI] 4.8-6.4) and 5.3 months (95% CI 2.6-8), respectively (p = 0.70). OS of the standard and intensified group were 11.1 months (95% CI 8.3-13.9) and 15.2 months (95% CI 12.7-17.7), respectively (p = 0.03). Repeated analysis excluding patients given any previous therapy revealed similar results. The intensified group had more fever and febrile neutropenia.

CONCLUSION

Trastuzumab combination with intensified chemotherapy provides better OS in first-line treatment of HER2-positive advanced gastric cancer. Further large-scale studies should be performed in HER2-positive patients.

Phase II Prospective Study of Trastuzumab in Combination with S-1 and Oxaliplatin (SOX100) Therapy for HER2-Positive Advanced Gastric Cancer

PURPOSE

The standard first-line treatment for human epidermal growth factor receptor type 2 (HER2)-positive advanced gastric cancer (AGC) is trastuzumab in combination with cisplatin and fluoropyrimidines. We evaluated the efficacy and safety of S-1 and oxaliplatin (100 mg/m²) (SOX100) combined with trastuzumab, a monoclonal antibody against HER2 for HER2-positive AGC.

METHODS

In this single-arm, multicenter phase II study, patients with HER2-positive AGC received S-1 (80-120 mg per day) orally on days 1-14, oxaliplatin (100 mg/m²) intravenously on day 1, and trastuzumab (8 mg/kg on day 1 of the first cycle, followed by 6 mg/kg every 3 weeks) intravenously. The primary end point was 1-year survival rate. The secondary end points included overall survival (OS), progression-free survival (PFS), overall response rate (ORR), and safety.

RESULTS

A total of 25 patients from six centers were enrolled from December 2015 to March 2020. In the 25 patients evaluable for analysis, the 1-year survival rate was 70.8% [90% confidence interval (CI) = 55.5-86.1%], whereas the median OS, PFS, and ORR were 17.8 (95% CI 10.5-22.9) months, 7.6 (95% CI 5.0-10.9) months, and 75.0% (95% CI 53.3-90.2), respectively. Major grade 3/4 adverse events included anorexia (20%), anemia (16%), peripheral sensory neuropathy (16%), and diarrhea (15%).

CONCLUSION

SOX100 combined with trastuzumab was effective with a favorable safety profile in patients with HER2-positive AGC.

HER2-Directed Therapy in Advanced Gastric and Gastroesophageal Adenocarcinoma: Triumphs and Troubles

OPINION STATEMENT

Gastric and gastroesophageal junction (GEJ) cancers represent the third leading cause of malignancy-associated death worldwide. Approximately 15-20% of these adenocarcinomas overexpress the human epidermal growth factor receptor 2 (HER2), a pro-proliferative receptor tyrosine kinase that has been therapeutically exploited in other disease contexts. The landmark ToGA trial demonstrated that trastuzumab, an anti-HER2 antibody, could improve overall survival for patients with HER2 overexpressing advanced gastric and GEJ adenocarcinomas. In the ensuing decade, great effort has been made to refine and expand this therapeutic strategy through a variety of avenues including optimization of chemotherapy backbones, identifying potential synergy with immune checkpoint inhibition, deployment of alternative HER2-targeted antibodies, use of small molecule inhibitors, and development of HER2-directed antibody drug conjugates. While the results of these efforts have had variable success, they have led to a greater understanding of the mechanisms of both primary and acquired resistance to HER2-directed therapies, laying the groundwork for future investigations. Recently, KEYNOTE-811 and DESTINY-Gastric01 have led to the FDA approvals of pembrolizumab in combination with trastuzumab and chemotherapy in the 1st-line advanced setting and trastuzumab deruxtecan (fam-trastuzumab deruxtecan-nxki) in the 2nd-line setting, respectively. Herein, we review these significant works as well as discuss the ongoing investigations they have inspired, which aim to find and utilize additional means for targeting HER2 in gastric and GEJ cancers.

Consensus recommendations for the standardized histopathological evaluation and reporting after radical oesophago-gastrectomy (HERO consensus)

BACKGROUND

Variation in the approach, radicality, and quality of gastroesophageal surgery impacts patient outcomes. Pathological outcomes such as lymph node yield are routinely used as surrogate markers of surgical quality, but are subject to significant variations in histopathological evaluation and reporting. A multi-society consensus group was convened to develop evidence-based recommendations for the standardized assessment of gastroesophageal cancer specimens.

METHODS

A consensus group comprised of surgeons, pathologists, and oncologists was convened on behalf of the Association of Upper Gastrointestinal Surgery of Great Britain & Ireland. Literature was reviewed for 17 key questions. Draft recommendations were voted upon via an anonymous Delphi process. Consensus was considered achieved where >70% of participants were in agreement.

RESULTS

Consensus was achieved on 18 statements for all 17 questions. Twelve strong recommendations regarding preparation and assessment of lymph nodes, margins, and reporting methods were made. Importantly, there was 100% agreement that the all specimens should be reported using the Royal College of Pathologists Guidelines as the minimum acceptable dataset. In addition, two weak recommendations regarding method and duration of specimen fixation were made. Four topics lacked sufficient evidence and no recommendation was made.

CONCLUSIONS

These consensus recommendations provide explicit guidance for gastroesophageal cancer specimen preparation and assessment, to provide maximum benefit for patient care and standardize reporting to allow benchmarking and improvement of surgical quality.

Treatment Patterns and Outcomes in Chinese Patients with Gastric Cancer by HER2 Status: A Noninterventional Registry Study (EVIDENCE)

BACKGROUND

Real-world safety and effectiveness data for trastuzumab plus chemotherapy treatment of patients with HER2-positive metastatic gastric cancer (mGC) in China are lacking.

PATIENTS AND METHODS

EVIDENCE was a prospective, multicenter, noninterventional registry study evaluating the safety and effectiveness of trastuzumab in five cohorts of Chinese patients with gastric cancer, stratified by HER2 status and trastuzumab treatment. Effectiveness was analyzed for cohorts I (HER2-positive, trastuzumab treated), II (HER2-positive, trastuzumab untreated), and IV (HER2-negative, trastuzumab untreated); trastuzumab-related adverse events (AEs) were analyzed for cohort I.

RESULTS

Cohorts I, II, and IV included 174, 113, and 422 patients, respectively. Most patients received first-line chemotherapy (87.6%). Median overall survival (OS1) for first-line treatment was 22.3, 17.2, and 17.4 months in cohorts I, II, and IV, respectively. After excluding patients who had surgery, respective median OS1 was 19.9, 15.3, and 12.9 months. Respective first-line progression-free survival (PFS1) was 8.2, 6.9, and 6.2 months; and respective first-line response rates (RR) were 51.7%, 18.4%, and 32.8%. Cohort I was significantly favored over cohort II for propensity score-matched first-line median OS1 (hazard ratio [HR], 0.61), PFS1 (HR, 0.64), and RR (odds ratio, 4.93). Trastuzumab-related AEs, grade 3-5 AEs, serious AEs, and AEs with a fatal outcome occurred in 23.6%, 3.4%, 2.3%, and 0.6% of cohort I patients, respectively.

CONCLUSION

Safety profiles were consistent with those known for trastuzumab and chemotherapy; trastuzumab treatment improved outcomes. Our study provides real-world data supporting first-line trastuzumab plus chemotherapy in Chinese patients with HER2-positive mGC.

IMPLICATIONS FOR PRACTICE

This prospective, noninterventional registry study aimed to provide safety and effectiveness data for the use of trastuzumab in combination with chemotherapy in Chinese patients with HER2-positive metastatic gastric cancer (mGC) from the real-world clinical setting. Trastuzumab plus first-line chemotherapy was shown to be safe and to improve outcomes when compared with patients treated with chemotherapy alone. Trastuzumab was effective within a range of treatment regimens; subgroup analysis showed that trastuzumab paired most effectively with the XELOX regimen. This study provides real-world clinical safety and effectiveness data supporting the use of trastuzumab in the treatment of Chinese patients with HER2-positive mGC.

Hopes and failures in front-line advanced HER2-positive gastric cancer therapy

Human epidermal growth-factor receptor 2 (HER2) was an important therapeutic target in gastric cancer. Through the last decade, strategy with trastuzumab-based chemotherapy remains the first-line standard of treatment in advanced HER2-positive gastric cancer. Based on the Trastuzumab for Gastric Cancer trial, trastuzumab plus systemic chemotherapy of cisplatin and fluoropyrimidine as the backbone was established as the first-line therapy in advanced HER2-positive gastric cancer. Since then, studies have explored the optimization of the front-line strategy, including the dose of trastuzumab, chemotherapy regimen and maintenance therapy. A large number of clinical trials were conducted to explore the optimal front-line therapy regimens, such as lapatinib and pertuzumab. Safe and effective first-line regimens are still lacking. Recently, two phase II studies of combining immune checkpoint inhibitor in first-line treatment of advanced HER2-positive gastric cancer showed promising results. The progress of immunotherapy has gradually promoted the development of front-line treatment of advanced HER2-positive gastric cancer to potential chemotherapy-free strategies. Therefore, this article reviewed these significant clinical trials and focus on the front-line treatment strategies for HER2-positive gastric cancer.

Human epidermal growth factor receptor 2 (HER2) in advanced gastric cancer: where do we stand?

Gastric cancer is one of the most common malignancy worldwide. In unresectable or metastatic disease, the prognosis is poor and in generally less than a year. HER2 expression remains an important biomarker to lead the addition of trastuzumab to first-line systemic chemotherapy in unresectable or metastatic gastroesophageal adenocarcinoma. To date, a major issue is represented by resistance to trastuzumab developed during treatment, considering the not improved outcomes in this molecular subtype of gastroesophageal adenocarcinoma to other HER2 target strategies. In this review, we summarize the available data on the mechanisms underlying primary and secondary resistance to HER2-targeted therapy and current challenges in the treatment of HER2-positive advanced gastric cancer refractory to trastuzumab. Furthermore, we describe the prognostic value of new non-invasive screening methods, under development novel agents (e.g., HER2 antibody-drug conjugates and bispecific antibodies) and strategies with antitumor activity in early studies.

Sustained Clinical Benefit of Pyrotinib Combined with Capecitabine Rescue Therapy After Trastuzumab Resistance in HER2-Positive Advanced Gastric Cancer: A Case Report

Background

HER2-positive patients with advanced gastric cancer have a poor prognosis, and trastuzumab-resistant patients lack effective treatment.

Case Presentation

We report a 72-year-old male with HER2-positive gastric cancer. The patient had metastatic tumor during adjuvant chemotherapy after surgery, followed by second-line chemotherapy, and achieved a progression-free survival (PFS) of 4.5 months. Subsequent third-line chemotherapy treatment also failed. Fortunately, the patient had a significant tumor response and 8.5 months of PFS on trastuzumab combined with chemotherapy. After trastuzumab resistance, the patient was treated with programmed cell death protein-1 inhibitor combined with apatinib, which selectively inhibited VEGFR2, but the effect was not satisfactory. Finally, the patient was treated with capecitabine combined with pyrotinib, an irreversible TKI, acting on HER2. The tumor shrank significantly after this treatment.

Conclusion

The mechanism and countermeasures of trastuzumab resistance were discussed in this case. For patients with HER2-positive advanced gastric cancer, pyrotinib can achieve good results after trastuzumab resistance.

Predictive Roles of HER2 Gene Amplification and Neutrophil-to-Lymphocyte Ratio on Survival in HER2-Positive Advanced Gastric Cancer Treated With Trastuzumab-Based Chemotherapy

OBJECTIVES

Trastuzumab is used as an agent against human epidermal growth factor receptor 2 (HER2)-positive advanced gastric cancer (AGC). The aim of this study was to determine how HER2 gene amplification and neutrophil-to-lymphocyte ratio (NLR) could predict long-term survival in AGC patients that underwent trastuzumab-based chemotherapy.

METHODS

We retrospectively reviewed medical records of 112 patients between 28 and 91 years old (median of 66 y) with AGC treated with first-line trastuzumab-based chemotherapy. The level of HER2 gene amplification was determined by the HER2/centromere enumerator probe 17 (CEP17) ratio and HER2 gene copy number (GCN). NLR was calculated as the neutrophil count divided by the lymphocyte counts.

RESULTS

Median HER2/CEP17 ratio, HER2 GCN, and NLR values were 2.85, 7.1, and 2.81, respectively. Objective response rate in both high HER2/CEP17 ratio (59.4% vs. 28.1%, P=0.012) and HER2 GCN groups (62.1% vs. 33.3%, P=0.032) was higher than that of each group. High NLR correlated with significantly worse median overall survival (OS) (median OS, 8.2 vs. 18.9 mo, P=0.002) and progression free survival (PFS) (median PFS: 5.1 vs. 8.0 mo, P=0.005). However, median OS and PFS were not significantly different according to HER2/CEP17 ratio or HER2 GCN. In the multivariate analysis, high NLR, Eastern Cooperative Group performance status, and poorly differentiated/signet ring cell type were independent factors for OS.

CONCLUSIONS

NLR was a significant predictor of long-term survival in AGC patients treated with first-line trastuzumab-based chemotherapy. Future validation of prospective trials with larger patient populations will be needed.

External validity of clinical trials with diverse trastuzumab-based chemotherapy regimens in advanced gastroesophageal adenocarcinoma: data from the AGAMENON-SEOM registry

BACKGROUND

Trastuzumab combined with cisplatin and fluoropyrimidines, either capecitabine or 5-fluorouracile (XP/FP), is the standard first-line treatment for advanced, HER2-positive, gastric cancer patients based on the ToGA trial. Despite the lack of phase III trials, many clinicians administer trastuzumab with alternative regimens. One meta-analysis suggests that substituting cisplatin for oxaliplatin might lead to greater efficacy and less toxicity.

METHODS

594 patients with HER2-positive gastroesophageal adenocarcinoma were recruited from the AGAMENON-SEOM registry. The objective was to evaluate the external validity of clinical trials with chemotherapy and trastuzumab.

RESULTS

The regimens used in at least 5% of the patients were XP (27%), oxaliplatin and capecitabine (CAPOX) (26%), oxaliplatin and 5-fluorouracil (FOLFOX) (14%), FP (14%), triplet with anthracycline/docetaxel (7%), and carboplatin-FU (5%). Median exposure to trastuzumab was longer with FOLFOX (11.4 months, 95% CI, 9.1-21.0) versus ToGA regimens (7.5, 6.4-8.5), p < 0.001. Patients with HER2-IHC 3+ cancers had higher response rates than those with IHC 2+/FISH+, odds-ratio 1.97 (95% CI, 1.25-3.09). The results achieved with CAPOX-trastuzumab were comparable to those attained with ToGA regimens. FOLFOX-trastuzumab was superior to ToGA schemes in terms of overall survival (OS), with a greater magnitude of effect in IHC 2+/FISH+ tumors (HR 0.47, 0.24-0.92) compared with IHC 3+ (HR 0.69, 0.49-0.96), and in diffuse (HR 0.37, 0.20-0.69) versus intestinal-type tumors (HR 0.76, 0.54-1.06).

CONCLUSION

We have updated the external validity of clinical trials with trastuzumab in first-line treatment of gastric cancer. Our data confirm the comparable outcomes of ToGA regimens and CAPOX-trastuzumab in clinical practice and point toward a possible benefit of FOLFOX-trastuzumab, contingent on the subtypes typically less sensitive to trastuzumab, to be confirmed in clinical trials.

FOLFIRINOX for the Treatment of Advanced Gastroesophageal Cancers: A Phase 2 Nonrandomized Clinical Trial

Importance

Standard first-line regimens for patients with metastatic gastroesophageal adenocarcinomas have an approximate 40% objective response rate (ORR). The combination of leucovorin, fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) has been efficacious as first-line therapy for other gastrointestinal cancers, such as pancreatic and colon cancers.

Objective

To evaluate the clinical activity and safety of FOLFIRINOX as first-line treatment for patients with advanced gastroesophageal adenocarcinoma.

Design, Setting, and Participants

This is an open-label, single-arm phase 2 study of first-line FOLFIRINOX in patients with advanced gastroesophageal adenocarcinoma. Estimated sample size included 41 patients with ERBB2-negative disease with 90% power to detect an ORR of 60% or greater with α of .10. No enrollment goal was planned for ERBB2-positive patients, but they were allowed to receive trastuzumab in combination with FOLFIRINOX.

Interventions

Starting doses were fluorouracil, 400 mg/m2 bolus, followed by 2400 mg/m2 over 46 hours; leucovorin, 400 mg/m2; irinotecan, 180 mg/m2; and oxaliplatin, 85 mg/m2. Trastuzumab was administered as a 6 mg/kg loading dose, followed by 4 mg/kg every 14 days in patients with ERBB2-positive disease.

Main Outcomes and Measures

The primary end point was ORR by the Response Evaluation Criteria in Solid Tumors, version 1.1. Secondary end points included safety profile, progression-free survival (PFS), overall survival (OS), and duration of response.

Results

From November 2013 to May 2018, 67 patients were enrolled (median [range] age, 59.0 [34-78] years; including 56 [84%] men), and 26 of 67 (39%) had ERBB2-positive disease. Median follow-up was 17.4 months. The ORR was 61%(95% CI, 44.5%-75.8%) (25 of 41) in the ERBB2-negative group and 85% (95% CI, 65.1%-95.6%) (22 of 26) in the ERBB2-positive group, including 1 patient with complete response. For ERBB2-negative patients, median PFS was 8.4 months and median OS was 15.5 months; for ERBB2-positive patients, median PFS was 13.8 months and median OS was 19.6 months. Fifty-six patients (84%) had dose modifications or treatment delays. The most common toxic effects were neutropenia (91%, n = 61), diarrhea (63%, n = 42), peripheral sensory neuropathy (61%, n = 41), and nausea (48%, n = 32), with no unexpected toxic effects.

Conclusions and Relevance

The FOLFIRINOX regimen with or without trastuzumab was associated with improved ORR and PFS in patients with advanced gastroesophageal adenocarcinoma in the first-line setting. This regimen may be a reasonable therapeutic option for patients with preserved performance status.

Trial Registration

ClinicalTrials.gov Identifier: NCT01928290.

Human Epidermal Growth Factor Receptor 2 (HER2) in Advanced Gastric Cancer: Current Knowledge and Future Perspectives

The discovery of human epidermal growth factor receptor 2 (HER2) overexpression in 15-20% of gastric adenocarcinomas has been a key advance in the global care of this disease. Validated by the ToGA trial in the first-line setting of advanced HER2-positive (+) gastric cancer (GC), trastuzumab, an anti-HER2 monoclonal antibody (mAb), was the first therapeutic agent to significantly improve the prognosis of these patients. Since these results, many attempts have been made to improve the clinical outcomes of patients with HER2+ GC. However, all the other HER2-targeting molecules have failed to show a survival benefit in large phase III studies. The value of continuing trastuzumab after disease progression has been suggested by several retrospective studies. However, recent results of a randomized phase II trial showed no benefit from this strategy. On the other hand, novel therapeutic methods, such as immunotherapy, are emerging as new tools in the strategy of care of advanced GC, even if their benefit in the specific HER2+ population remains undetermined. Furthermore, substantial progress has been made in the understanding of the mechanisms leading to resistance to anti-HER2 therapies, and in the screening methods to detect them, thus opening new perspectives. The aim of this review was firstly to summarize the existing data on the specific strategy of care of HER2+ advanced GC, and secondly, to describe current knowledge regarding the potential mechanisms of resistance to HER2-targeting therapies. Lastly, we report the prospects for overcoming these potential obstacles, from future therapeutic strategies to new detection methods.

Germacrone Regulates HBXIP-Mediated Cell Cycle, Apoptosis and Promotes the Formation of Autophagosomes to Inhibit the Proliferation of Gastric Cancer Cells

Germacrone, a monocyclic sesquiterpene, exerts marked antitumor effects in a variety of cancers, including hepatocellular carcinoma, gastric cancer, and breast cancer. However, the mechanism underlying the effects of germacrone on gastric cancer remains unclear. In this study, we show that germacrone inhibited gastric cancer cell proliferation in a dose-dependent manner, and induced G0/G1-phase cell cycle arrest and apoptosis in these cells. Moreover, germacrone increased the expression of LC3II/LC3I. And LC3II/LC3I was significant increased after germacrone treatment compared with germacrone and bafilomycin A1 (Baf A1) treatment, which suggested germacrone promoted the formation of autophagosomes. Proteomic analysis was then used to identify molecular targets of germacrone in gastric cancer. A total of 596 proteins were screened, and the top hit was identified as late endosomal/lysosomal adaptor and MAPK and MTOR activator 5 (LAMTOR5, also named HBXIP). Overexpression of HBXIP delayed the germacrone-induced cell cycle arrest, induction of apoptosis, and inhibition of autophagy. Combined, our results indicate that germacrone suppresses gastric cancer cell proliferation by inhibiting HBXIP, and this process is related to G0/G1-phase arrest and apoptosis.

Clinical significance of peripheral blood-derived inflammation markers in advanced gastric cancer after radical resection

Background

The prognostic significance of peripheral blood-derived inflammation markers in patients with gastric cancer (GC) has not been elucidated. This study aimed to investigate the relationship between systemic inflammatory markers and GC prognosis.

Methods

A prospective observational cohort study involving 598 patients was conducted to analyze the prognosis of GC based on systemic inflammatory markers. The following peripheral blood-derived inflammation markers were evaluated: the neutrophil-lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), systemic immune-inflammation index (SII), C-reactive protein/albumin (CRP/Alb) ratio, Glasgow Prognostic Score (GPS), modified Glasgow Prognostic Score (mGPS), prognostic nutrition index (PNI), and prognostic index (PI). The receiver operating characteristics (ROC) curve and the Youden index were used to determine the optimal cutoff values. Univariate and multivariate analysis of prognostic factors was conducted accordingly.

Results

The optimal cutoff values of the PNI, fibrinogen, NLR, PLR, SII, and CRP/Alb were 49.5, 397 ng/dl, 2.5, 154, 556, and 0.05, respectively. Multivariate analysis showed that age, PLR, TNM stage, and chemotherapy were the independent prognostic factors for advanced gastric cancer (AGC). Adjuvant chemotherapy improved the long-term prognosis of patients with PLR ≥154, but chemotherapy had no significant effect on the survival of patients with PLR < 154.

Conclusions

Our findings show that higher PLR (≥154) is an independent risk factor for poor prognosis in GC patients. Besides, PLR can predict adjuvant chemotherapy (oxaliplatin/5-fluorouracil combination) response in patients with GC after surgery.

Systemic Treatment of Patients With Gastrointestinal Cancers During the COVID-19 Outbreak: COVID-19-adapted Recommendations of the National Cancer Institute of Milan

The current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak poses a major challenge in the treatment decision-making of patients with cancer, who may be at higher risk of developing a severe and deadly SARS-CoV-2 infection compared with the general population. The health care emergency is forcing the reshaping of the daily assessment between risks and benefits expected from the administration of immune-suppressive and potentially toxic treatments. To guide our clinical decisions at the National Cancer Institute of Milan (Lombardy region, the epicenter of the outbreak in Italy), we formulated Coronavirus-adapted institutional recommendations for the systemic treatment of patients with gastrointestinal cancers. Here, we describe how our daily clinical practice has changed due to the pandemic outbreak, with the aim of providing useful suggestions for physicians that are facing the same challenges worldwide.

Targeted therapies for gastroesophageal cancers

Gastroesophageal cancers are some of the most common malignancies worldwide. A significant portion of patients are diagnosed with advanced or metastatic disease given the insidious nature of gastroesophageal cancers. In the instance where surgical resection for cure is no longer an option, the prognosis is poor and generally less than a year. Traditionally, standard front-line chemotherapy included two- to three-drug regimens with modest improvements in overall survival. Over the past two decades, with increased understanding of the biology of cancer, targeted therapies have been developed to stop the actions of molecules that are key in the growth and spread of cancer cells and have been successful in a number of cancers. In gastroesophageal cancer, these gains have been more modest with limited approval-trastuzumab being incorporated into front-line use in HER2-positive disease, and ramucirumab alone or in combination with paclitaxel becoming the preferred second-line regimen in progressive disease. However, with increased understanding of the biology of cancer, new and promising targeted therapies have emerged along with novel strategies in combining targeted therapies with traditional chemotherapy and immunotherapy. In this article, we will review the use of targeted therapies in the treatment of gastroesophageal cancer and touch upon future treatment strategies and therapeutics currently under investigation.

Minimally invasive surgery is feasible after preoperative chemotherapy for stage IV gastric cancer

AIM

To elucidate the safety and feasibility of minimally invasive surgery (MIS) as conversion surgery after chemotherapy for stage IV gastric cancer, we compared the background characteristics and clinical courses of patients who underwent open conversion surgery (open group) versus MIS (MIS group).

METHODS

We included 94 consecutive patients with stage IV gastric cancer who received chemotherapy followed by conversion surgery gastric resection from January 2011 to October 2019 at the Osaka International Cancer Institute in this analysis.

RESULTS

The open group included more patients who had macroscopic peritoneal metastasis and required splenectomy. However, other background characteristics, including preoperative chemotherapy duration, were comparable. The MIS group had significantly longer operative time (266 vs 339 minutes, P = .0039) and less operative blood loss (520 vs 10 mL, P < .0001). The incidence of postoperative complication of Clavien-Dindo grade II or higher was non-significantly lower (24.5% vs 9.8%, P = .058) and length of postoperative hospital stay was significantly shorter in the MIS group (12 vs 8 days, P < .0001). Even though the open group included more patients with more advanced (ypT4a or higher, or N3) disease, the MIS group had better recurrence free survival and overall survival (OS). Multivariate analysis revealed that N status (hazard ratio [HR], 4.39; 95% confidence interval [CI], 2.18-12.26; P < .0001) and T status (2.11; 1.05-4.36; P = .036) were independent prognostic factors for OS. MIS was not a negative prognostic factor for OS (HR, 0.44; 95% CI, 0.15-1.10; P = .081).

CONCLUSION

MIS can be safely performed as conversion surgery following chemotherapy for stage IV gastric cancer.

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.

Emerging Targeted Therapies for HER2 Positive Gastric Cancer That Can Overcome Trastuzumab Resistance

Trastuzumab, a monoclonal antibody to human epidermal growth factor receptor 2 (HER2), has improved survival in patients with HER2-positive advanced gastric or gastroesophageal junction cancer (AGC). The inevitable development of resistance to trastuzumab remains a problem, however, with several treatment strategies that have proven effective in breast cancer having failed to show clinical benefit in AGC. In this review, we summarize the mechanisms underlying resistance to HER2-targeted therapy and outline past and current challenges in the treatment of HER2-positive AGC refractory to trastuzumab. We further describe novel agents such as HER2 antibody-drug conjugates that are under development and have shown promising antitumor activity in early studies.

A case of stage IV gastric cancer with para-aortic lymph node metastasis showing pathological complete response after neoadjuvant chemotherapy

Background

Stage IV advanced gastric cancer with para-aortic lymph node metastasis (PALM) is considered unresectable. Systemic chemotherapy is the treatment of choice for such tumors, while conversion surgery may be a treatment option in the case chemotherapy is effective but R0 resection is possible. We report a case of stage IV gastric cancer with PALM that showed pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) using S-1, oxaliplatin, and trastuzumab (SOX+HER).

Case presentation

A 69-year-old woman who was diagnosed with type 4 stage IV gastric cancer with PALM underwent five courses of NAC with the SOX+HER regimen. The primary tumor and the PALM shrank after treatment, suggesting that the NAC induced a partial response. We performed a total gastrectomy plus distal pancreaticosplenectomy with para-aortic lymph node dissection. Histological analysis revealed no remnant cancer cells in the primary tumor or the lymph nodes, confirming a pCR. The postoperative course was uneventful, and the patient was discharged on day 14 after the operation. S-1 was started as adjuvant chemotherapy, and the patient remains alive without recurrence 2 months after surgery.

Conclusion

This case shows the possibility of conversion surgery after SOX+HER therapy for stage IV advanced gastric cancer with PALM.

A prospective observational study on the optimal maintenance strategy in HER2-positive advanced gastric cancer treated with trastuzumab-based therapy

PURPOSE

Trastuzumab plus chemotherapy is an effective therapy in HER2 positive advanced gastric cancer (AGC). However, the optimal maintenance treatment in patients benefited from the first line therapy remains unclear.

METHODS

In this prospective observational study, patients with HER2 positive AGC who received six cycles of trastuzumab-based first line chemotherapy were divided into two arms according to the maintenance strategy: trastuzumab monotherapy (arm A) and trastuzumab plus mono-chemo-agent derived from the initial chemotherapy (arm B). The primary end point was overall survival (OS), the secondary end points were first line progression free survival (PFS), maintenance PFS, cost-effectiveness ratios (CERs), incremental cost-effectiveness ratios (ICERs) and safety.

RESULTS

30 patients were in arm A received trastuzumab monotherapy and 48 were in arm B. The clinical and pathological characteristics of two arms were well balanced. There was no significant difference of median OS (16.5 vs 20.0 months, HR 0.71 P = 0.169) or PFS (7.9 vs 11.0, HR 1.06, P = 0.892) between two arms, however, adding chemo-agent could lead to a 29% reduction in mortality risk. Adverse effects including cardiac safety were also similar. Subgroup analysis showed chemotherapy additional to trastuzumab benefited on OS in patients who had stable disease (SD) of response (HR: 0.084, P = 0.004), elder than 65 years old (HR: 0.4, P = 0.015), without liver metastasis (HR: 0.271, P = 0.008) or less than two organs of distance metastasis (HR: 0.263, P = 0.005). The average cost per patients in arm A was 153,137 RMB and 165,195 RMB in arm B. While, ICER in arm A was 1.29 times higher than arm B (CERs of two arms were 19,384 vs 15,018 RMB).

CONCLUSION

Mono-chemo-agent combined with trastuzumab showed an advantage of absolute value and hazard ratio on OS, in addition to ICER of PFS for patients who benefit from the initial six cycles of trastuzumab-based first line therapy, especially in patients with certain clinical or treatment-related characterisitics. A large sample randomized trial is warranted.