Randomized trial on adjuvant treatment with FOLFIRI followed by docetaxel and cisplatin versus 5-fluorouracil and folinic acid for radically resected gastric cancer

Management of Microsatellite Instability High (MSI-H) Gastroesophageal Adenocarcinoma

BACKGROUND

Gastroesophageal cancer is a major cause of cancer-related mortality worldwide. Treatment of both early stage and advanced disease remains highly reliant on cytotoxic chemotherapy. About 4-24% of gastroesophageal cancers are microsatellite instability high (MSI-H). The MSI-H subtype is associated with favorable prognosis, resistance to cytotoxic chemotherapy, and sensitivity to immune checkpoint inhibitors (ICI). Recent studies have demonstrated promising activity of ICIs in the MSI-H subtype, resulting in fundamental changes in the management of MSI-H gastroesophageal adenocarcinoma.

PURPOSE

In this review, we discuss the prevalence, characteristics, prognosis, and management of MSI-H gastroesophageal adenocarcinoma, with a focus on recent and ongoing studies that have changed the landscape of treatment for the MSI-H subtype. We also discuss current challenges in the management of resectable and advanced MSI-H gastroesophageal cancer, including the need for more accurate biomarkers of response to ICI therapy.

Locally Advanced Gastric Cancer Management: A Cost-Effectiveness Analysis

Across the nation, patients with locally advanced gastric cancer (LAGC) are managed with modalities including upfront surgery (US) and perioperative chemotherapy (PCT). Preoperative therapies have demonstrated survival benefits over US and thus long-term outcomes are expected to vary between the options. However, as these 2 modalities continue to be regularly employed, we sought to perform a decision analysis comparing the costs and quality-of-life associated with the treatment of patients with LAGC to identify the most cost-effective option. We designed a decision tree model to investigate the survival and costs associated with the most commonly utilized management modalities for LAGC in the United States: US and PCT. The tree described costs and treatment strategies over a 6-month time horizon. Costs were derived from 2022 Medicare reimbursement rates using the third-party payer perspective for physicians and hospitals. Effectiveness was represented using quality-adjusted life-years (QALYs). One-way, two-way, and probabilistic sensitivity analyses were utilized to test the robustness of our findings. PCT was the most cost-effective treatment modality for patients with LAGC over US with a cost of $40,792.16 yielding 3.11 QALYs. US has a cost of $55,575.57 while yielding 3.15 QALYs; the incremental cost-effectiveness ratio (ICER) was $369,585.25. One-way and two-way sensitivity analyses favored PCT in all variations of variables across their standard deviations. Across 100,000 Monte Carlo simulations, 100% of trials favored PCT. In our model simulating patients with LAGC, the most cost-effective treatment strategy was PCT. While US demonstrated improved QALYs over PCT, the associated cost was too great to justify its use.

Adjuvant treatment for locally advanced gastric cancer: an Asian perspective

Standard adjuvant treatment for locally advanced gastric cancer (LAGC) is regionally different. Whereas perioperative chemotherapy is the standard in Western populations, D2 gastrectomy followed by adjuvant chemotherapy has been the standard in East Asia. Recently, the pivotal phase 3 PRODIGY and RESOLVE studies have demonstrated survival benefits of adding neoadjuvant chemotherapy to surgery followed by adjuvant chemotherapy over up-front surgery followed by adjuvant chemotherapy in Asian patients. Based on these results, neoadjuvant chemotherapy is considered one of the viable options for patients with LAGC. In this review, various aspects of neoadjuvant chemotherapy will be discussed for its optimal application in Asia. Candidates for neoadjuvant chemotherapy should be carefully chosen in consideration of the inaccurate aspects of radiological clinical staging and its potential benefit over up-front surgery followed by a decision on adjuvant chemotherapy according to the pathological stage. Efforts should continuously be made to optimally apply neoadjuvant chemotherapy to patients with LAGC, considering various factors, including a more accurate radiological assessment of the tumor burden and the optimization of post-operative chemotherapy. Future neoadjuvant trials involving novel agents for Asian patients should be designed based on proven Asian regimens rather than adopting Western regimens.

Prognostic and predictive impact of sex in locally advanced microsatellite instability high gastric or gastroesophageal junction cancer: An individual patient data pooled analysis of randomized clinical trials

BACKGROUND

Surgery plus peri-operative/adjuvant chemotherapy is the standard of care for locally advanced GC/GEJC, though with unsatisfactory results. dMMR/MSI-high tumors have better prognosis and scant benefit from chemotherapy as compared to pMMR/MSS ones. The differential outcome of therapies in terms of safety and efficacy according to sex is still debated in GC/GEJC patients.

METHODS

We previously performed an individual patient data pooled analysis of MAGIC, CLASSIC, ITACA-S, and ARTIST trials including GC/GEJC patients treated with surgery alone or surgery plus peri-operative/adjuvant chemotherapy to assess the value of MSI status. We performed a secondary analysis investigating the prognostic and predictive role of sex (female versus male) in the pooled analysis dataset in the overall population and patients stratified for MSI status (MSI-high versus MSS/MSI-low). Disease-free (DFS) and overall survival (OS) were calculated.

RESULTS

Patients with MSI-high tumors had improved survival as compared to MSS/MSI-low ones irrespective of sex, whereas in those with MSS/MSI-low tumors, females had numerically longer OS and DFS (5-year OS was 63.2% versus 57.6%, HR 0.842; p = 0.058, and 5-year DFS was 55.8% versus 50.8%, HR 0.850; p = 0.0504 in female versus male patients). The numerical difference for the detrimental effect of chemotherapy in MSI-high GC was higher in females than males, while the significant benefit of chemotherapy over surgery alone was confirmed in MSS/MSI-low GC irrespective of sex.

CONCLUSIONS

This pooled analysis including four randomized trials highlights a relevant impact of sex in the prognosis and treatment efficacy of MSI-high and MSS/MSI-low non-metastatic GC/GEJC.

Adjuvant Concurrent Chemoradiotherapy (CRT) plus Docetaxel-Cisplatin-Fluorouracil (DCF) versus CRT plus Fluorouracil-Folinic Acid (FUFA) in Stage III Gastric Cancer

INTRODUCTION

Adjuvant chemoradiotherapy (CRT) is the optimal management strategy in resectable gastric cancer. There is a debate about the efficacy of more aggressive CRT plus chemotherapy regimens in adjuvant setting. This study aimed to compare the efficacy of adjuvant CRT plus docetaxel-cisplatin-fluorouracil (DCF) versus CRT plus fluorouracil-folinic acid (FUFA) in stage III gastric cancer.

METHODS

Patients with a diagnosis of stage III gastric cancer treated with adjuvant therapy after curative resection were analyzed. Patients' disease characteristics and impacts of the regimens on median disease-free survival (DFS) and median overall survival (OS) were analyzed retrospectively.

RESULTS

One hundred sixty-one patients (102 in FUFA arm and 59 in DCF arm) with a median age of 56.0 (29-79) were evaluated. In the DCF arm, there were more renal toxicities (31.6% vs 6.4% P < 0.001), emergency department admissions (64.9% vs 23.7%, P < 0.001), and dose reductions/treatment modifications in the DCF arm (51.6% vs 37.2, P < 0.001). The median follow-up was 23 months (1-124) in the FUFA arm and 26.0 months (1-77) in the DCF arm. The median DFS was 25.0 months (%95 CI, 12.7-37.2) in the DCF arm and 17.0 months (%95 CI, 2.6-31.3) in the FUFA arm, P = 0.66. The median OS was 28.0 months (%95 CI, 17.0-38.9) in the DCF arm and 25.0 months (%95 CI, 11.9-36.0) in the FUFA arm, P = 0.70.

CONCLUSION

In conclusion, when compared with FUFA regimen, more aggressive therapy with DCF was more toxic and did not improve OS in adjuvant setting of stage III gastric cancer.

The Chinese Society of Clinical Oncology (CSCO): Clinical guidelines for the diagnosis and treatment of gastric cancer, 2023

The 2023 update of the Chinese Society of Clinical Oncology (CSCO) Clinical Guidelines for Gastric Cancer focuses on standardizing cancer diagnosis and treatment in China, reflecting the latest advancements in evidence-based medicine, healthcare resource availability, and precision medicine. These updates address the differences in epidemiological characteristics, clinicopathological features, tumor biology, treatment patterns, and drug selections between Eastern and Western gastric cancer patients. Key revisions include a structured template for imaging diagnosis reports, updated standards for molecular marker testing in pathological diagnosis, and an elevated recommendation for neoadjuvant chemotherapy in stage III gastric cancer. For advanced metastatic gastric cancer, the guidelines introduce new recommendations for immunotherapy, anti-angiogenic therapy and targeted drugs, along with updated management strategies for human epidermal growth factor receptor 2 (HER2)-positive and deficient DNA mismatch repair (dMMR)/microsatellite instability-high (MSI-H) patients. Additionally, the guidelines offer detailed screening recommendations for hereditary gastric cancer and an appendix listing drug treatment regimens for various stages of gastric cancer. The 2023 CSCO Clinical Guidelines for Gastric Cancer updates are based on both Chinese and international clinical research and expert consensus to enhance their applicability and relevance in clinical practice, particularly in the heterogeneous healthcare landscape of China, while maintaining a commitment to scientific rigor, impartiality, and timely revisions.

Neoadjuvant chemotherapy for locally advanced gastric cancer in Japan: Consensus meeting at the 77th general meeting of the Japanese Society of Gastroenterological Surgery

Treatment strategy for locally advanced gastric cancer differs worldwide. Neoadjuvant chemotherapy (NAC) is considered one of the promising treatment options for locally advanced gastric cancer, even in Japan, and clinical trials have been conducted or are ongoing. A consensus meeting was organized at the 77th general meeting of the Japanese Society of Gastroenterological Surgery in 2022, in which the current status and future prospects of NAC for locally advanced gastric cancer were discussed. Participants at the meeting looked forward to the results of the JCOG1509 trial, providing solid evidence regarding NAC. The optimal indications and regimens for NAC were also debated. Patients with cStage III gastric cancer are the main targets of NAC in Japan, and a doublet regimen of S-1 and oxaliplatin was preferred by the participants. However, the feasibility of a triplet regimen with S-1, oxaliplatin, and docetaxel, and that with 5-FU, leucovorin, oxaliplatin, and docetaxel has been demonstrated, and these could become treatment options in Japan. Other points of discussion include perioperative chemotherapy to avoid peritoneal recurrence and for patients with dMMR/MSI-high tumors. The panel regarded NAC as a promising treatment option, and NAC will become the standard treatment for cStage III gastric cancer in Japan if an ongoing clinical trial successfully demonstrates its efficacy.

Impact of mismatch repair deficiency on tumour regression grade after neoadjuvant chemotherapy in localized gastroesophageal adenocarcinoma

BACKGROUND

The use of neoadjuvant chemotherapy (NAC) in patients with mismatch repair (MMR) deficient (dMMR) localized gastric and oeso-gastric junction (OGJ) adenocarcinoma is subject of debate. Histological response assessment might help to better evaluate the impact of dMMR on response to NAC.

METHODS

Patients with localized gastric/OGJ adenocarcinoma resected after NAC were retrospectively identified. MMR protein expression status was assessed by immunohistochemistry. The primary objective was the frequency of histological responders to NAC defined by tumour regression grade (TRG) using Mandard's (TRG1-2) and Becker's (TRG1) classifications, according to the MMR status.

RESULTS

In total, 247 patients with 43 dMMR and 204 pMMR gastric/OGJ adenocarcinoma were identified. Among dMMR tumours, 18 (42%) arose from the OGJ. Histological response (Becker TRG1-2) was observed for 28% and 35% of dMMR and pMMR tumours, respectively (p = 0.35). Similar results were observed with Mandard classification. With a median follow-up of 37.5 months, median disease-free and overall survival were not reached for the dMMR group.

CONCLUSION

Histological response after NAC in patients with localized dMMR gastric/OGJ adenocarcinoma is not statistically different to those with pMMR tumours. This study provides additional data for the discussion about avoiding NAC in patients with dMMR gastric/OGJ adenocarcinomas.

Controversies and management of deficient mismatch repair gastrointestinal cancers in the neoadjuvant setting

High microsatellite instability (MSI-H)/deficient mismatch repair (dMMR) phenotype is a distinct molecular signature across gastrointestinal cancers characterized by high tumor mutational burden and high neoantigen load. Tumors harboring dMMR are highly immunogenic and heavily infiltrated by immune cells; consequently, they are uniquely vulnerable to therapeutic strategies enhancing immune antitumor response such as checkpoint inhibitors. The MSI-H/dMMR phenotype arose as a powerful predictor of response to immune checkpoint inhibitors with evidence supporting significantly improved outcomes in the metastatic setting. On the other hand, the genomic instability characteristic of MSI-H/dMMR tumors appears to be associated with decreased sensitivity to chemotherapy, and the benefits of standard adjuvant or neoadjuvant chemotherapy approaches in this subtype are being increasingly questioned. Here, we review the prognostic and predictive impact of MMR status in localized gastric and colorectal cancers, and highlight the emerging clinical data incorporating checkpoint inhibitors in the neoadjuvant setting.

EBV and MSI Status in Gastric Cancer: Does It Matter?

We investigated the impactof microsatellite instability (MSI) and Epstein-Barr virus (EBV) status in gastric cancer (GC), regarding response to perioperative chemotherapy (POPChT), overall survival (OS), and progression-free survival (PFS). We included 137 cases of operated GC, 51 of which were submitted to POPChT. MSI status was determined by multiplex PCR and EBV status by EBV-encoded RNA in situ hybridization. Thirty-seven (27%) cases presented as MSI-high, and seven (5.1%) were EBV+. Concerning tumor regression after POPChT, no differences were observed between the molecular subtypes, but females were more likely to respond (p = 0.062). No significant differences were found in OS or PFS between different subtypes. In multivariate analysis, age (HR 1.02, IC 95% 1.002-1.056, p = 0.033) and positive lymph nodes (HR 1.82, IC 95% 1.034-3.211, p = 0.038) were the only prognostic factors for OS. However, females with MSI-high tumors treated with POPChT demonstrated a significantly increased OS compared to females with MSS tumors (p = 0.031). In conclusion, we found a high proportion of MSI-high cases. MSI and EBV status did not influence OS or PFS either in patients submitted to POPChT or surgery alone. However, superior survival of females with MSI-high tumors suggests that sex disparities and molecular classification may influence treatment options in GC.

American Radium Society (ARS) Appropriate Use Criteria (AUC) for Locoregional Gastric Adenocarcinoma: Systematic Review and Guidelines

OBJECTIVE

The objective of this study was to systematically evaluate the data regarding the use of neoadjuvant, perioperative, surgical, and adjuvant treatment options in localized gastric cancer patients and to develop Appropriate Use Criteria recommended by a panel of experts convened by the American Radium Society.

METHODS

Preferred reporting items for systematic reviews and meta-analyses methodology was used to develop an extensive analysis of peer-reviewed phase 2/2R/3 trials, as well as meta-analyses found within the Ovid Medline database between 2010 and 2020. The expert panel then rated the appropriateness of various treatments in 5 representative clinical scenarios through a well-established consensus methodology (modified Delphi).

RESULTS

For patients with medically operable locally advanced gastric cancer, the strongest recommendation was for perioperative chemotherapy based on high-quality data. Acceptable alternatives included surgery followed by either chemotherapy or concurrent chemoradiotherapy (CRT). For patients with upfront resection of stages I to III gastric cancer (no neoadjuvant therapy), the group strongly recommended adjuvant therapy with either chemotherapy alone or CRT, based on high-quality data. For patients with locally advanced disease who received preoperative chemotherapy without tumor regression, the group strongly recommended postoperative chemotherapy or postoperative CRT. Finally, for medically inoperable gastric cancer patients, there was moderate consensus recommending definitive concurrent CRT.

CONCLUSIONS

The addition of chemotherapy and/or radiation, either in the neoadjuvant, adjuvant, or perioperative setting, results in improved survival rates for patients compared with surgery alone. For inoperable patients, definitive CRT is a reasonable treatment option, though largely palliative.

Neoadjuvant and Adjuvant Therapy Approaches to Gastric Cancer

OPINION STATEMENT

Gastric cancer is an aggressive malignancy, requiring a multimodality approach to achieve optimal curative rates even when the disease is amenable to surgical resection. Neoadjuvant and adjuvant approaches differ across the globe-a preference for peri-operative chemotherapy exists in Europe, in contrast to the adoption of adjuvant chemotherapy in Asia and adjuvant chemoradiotherapy in North America. There are nuances and limitations associated with each therapeutic strategy and an understanding of these distinct approaches is integral to judicious clinical application of the available data. Although a multimodal approach provides a clear survival benefit above a surgical-only approach, data report low completion rates of adjuvant therapy components and strongly suggest a need to refine patient selection particularly for ongoing treatment in the post-operative period. This may be achieved using a risk-stratified strategy. Hence, there is a need to transition from a generalised approach to a multimodality treatment towards one guided by individual patient clinical features and biomarker profiles in order to improve tolerability and patient outcomes irrespective of geographical variation in clinical practice. While the evidences supporting molecular features such as microsatellite instability and predictive gene signatures are provocative, prospective validation is required before these can be confidently used to direct clinical decision-making.

Immunotherapy-Based Neoadjuvant Treatment of Advanced Microsatellite Instability-High Gastric Cancer: A Case Series

Despite the use of first-line therapies like fluoropyrimidine and platinum-based cytotoxic chemotherapy, gastric cancer (GC) continues to carry a poor prognosis. Recent subgroup analyses of first-line phase III trials have demonstrated that patients with microsatellite instability-high (MSI-H) metastatic GC derive significant improvement in survival rates when immune checkpoint inhibitors (ICIs) are combined with chemotherapy compared with chemotherapy alone. However, it remains to be seen whether the success of ICIs in the metastatic setting can be translated into earlier stages of GC with resectable disease. We report 6 cases of locally advanced, nonmetastatic MSI-H GC that all demonstrated favorable response following treatment with pembrolizumab in addition to neoadjuvant chemotherapy. With the exception of immune-related colitis in one patient, pembrolizumab was well-tolerated. To our knowledge, this is the first reported US case series of patients treated with an ICI in combination with neoadjuvant chemotherapy for advanced, nonmetastatic, resectable or unresectable MSI-H GC.

Approach to Resectable Gastric Cancer: Evolving Paradigm of Neoadjuvant and Adjuvant Treatment

OPINION STATEMENT

Recent therapeutic advances have prolonged survival in patients with metastatic gastric cancer, though the prognosis for patients with locally advanced resectable gastric cancer remains poor. Long-term survival after resection of locally advanced gastric adenocarcinoma is dependent on early eradication of micrometastatic disease and optimal surgical resection. Preoperative therapy with a docetaxel-containing three-drug regimen has recently been shown to be superior to an anthracycline-containing three-drug regimen or two-drug therapy with a fluoropyrimidine and platinum. Chemoradiation is not essential and is reserved for patients with suboptimal resection. Emerging research strategies include introduction of pre- and postoperative checkpoint blockade and biomarker-directed therapy.

Risk-adapted modulation through de-intensification of cancer treatments: an ESMO classification

BACKGROUND

The landscape of clinical trials testing risk-adapted modulations of cancer treatments is complex. Multiple trial designs, endpoints, and thresholds for non-inferiority have been used; however, no consensus or convention has ever been agreed to categorise biomarkers useful to inform the treatment intensity modulation of cancer treatments.

METHODS

An expert subgroup under the European Society for Medical Oncology (ESMO) Precision Medicine Working Group shaped an international collaborative project to develop a classification system for biomarkers used in the cancer treatment de-intensification, based on a tiered approach. A group of disease-oriented clinical, translational, methodology and public health experts, and patients' representatives provided an analysis of the status quo, and scanned the horizon of ongoing clinical trials. The classification was developed through multiple rounds of expert revisions and inputs.

RESULTS

The working group agreed on a univocal definition of treatment de-intensification. Evidence of reduction in the dose-density, intensity, or cumulative dose, including intermittent schedules or shorter treatment duration or deletion of segment(s) of the standard regimens, compound(s), or treatment modality must be demonstrated, to define a treatment de-intensification. De-intensified regimens must also portend a positive impact on toxicity, quality of life, health system burden, or financial toxicity. ESMO classification categorises the biomarkers for treatment modulation in three tiers, based on the level of evidence. Tier A includes biomarkers validated in prospective, randomised, non-inferiority clinical trials. The working group agreed that in non-inferiority clinical trials, boundaries are highly dependent upon the disease scenario and endpoint being studied and that the absolute differences in the outcomes are the most relevant measures, rather than relative differences. Biomarkers tested in single-arm studies with a threshold of non-inferiority are classified as Tier B. Tier C is when the validation occurs in prospective-retrospective quality cohort investigations.

CONCLUSIONS

ESMO classification for the risk-guided intensity modulation of cancer treatments provides a set of evidence-based criteria to categorise biomarkers deemed to inform de-intensification of cancer treatments, in risk-defined patients. The classification aims at harmonising definitions on this matter, therefore offering a common language for all the relevant stakeholders, including clinicians, patients, decision-makers, and for clinical trials.

Machine-learning model derived gene signature predictive of paclitaxel survival benefit in gastric cancer: results from the randomised phase III SAMIT trial

OBJECTIVE

To date, there are no predictive biomarkers to guide selection of patients with gastric cancer (GC) who benefit from paclitaxel. Stomach cancer Adjuvant Multi-Institutional group Trial (SAMIT) was a 2×2 factorial randomised phase III study in which patients with GC were randomised to Pac-S-1 (paclitaxel +S-1), Pac-UFT (paclitaxel +UFT), S-1 alone or UFT alone after curative surgery.

DESIGN

The primary objective of this study was to identify a gene signature that predicts survival benefit from paclitaxel chemotherapy in GC patients. SAMIT GC samples were profiled using a customised 476 gene NanoString panel. A random forest machine-learning model was applied on the NanoString profiles to develop a gene signature. An independent cohort of metastatic patients with GC treated with paclitaxel and ramucirumab (Pac-Ram) served as an external validation cohort.

RESULTS

From the SAMIT trial 499 samples were analysed in this study. From the Pac-S-1 training cohort, the random forest model generated a 19-gene signature assigning patients to two groups: Pac-Sensitive and Pac-Resistant. In the Pac-UFT validation cohort, Pac-Sensitive patients exhibited a significant improvement in disease free survival (DFS): 3-year DFS 66% vs 40% (HR 0.44, p=0.0029). There was no survival difference between Pac-Sensitive and Pac-Resistant in the UFT or S-1 alone arms, test of interaction p<0.001. In the external Pac-Ram validation cohort, the signature predicted benefit for Pac-Sensitive (median PFS 147 days vs 112 days, HR 0.48, p=0.022).

CONCLUSION

Using machine-learning techniques on one of the largest GC trials (SAMIT), we identify a gene signature representing the first predictive biomarker for paclitaxel benefit.

TRIAL REGISTRATION NUMBER

UMIN Clinical Trials Registry: C000000082 (SAMIT); ClinicalTrials.gov identifier, 02628951 (South Korean trial).

Localized stomach cancer: Perioperative or postoperative approach? A meta‐analysis of phase III studies

Background and Aim

Despite the development and standardization of surgical techniques in the treatment of localized gastric adenocarcinoma, the loco‐regional and metastatic recurrence rate remains high. A combined radiochemotherapeutic regimen (the MacDonald regimen) as well as perioperative chemotherapy allows a significant improvement in the survival of patients with localized gastric adenocarcinoma with a reduction in the recurrence rate compared to surgery alone. The purpose of this review is to specify the best therapeutic approach in the treatment of localized gastric cancer.

Methods

We performed a systemic search of Medline, Embase, and the Cochrane Central Register of Controlled Trials using PubMed, Google Scholar, and Ovid without language restriction. Hazard ratio (HR) with 95% confidence interval (CI) was reported.

Results

We pooled 727 patients from two phase III randomized controlled trials. There was a benefit of perioperative chemotherapy versus surgery alone on the overall survival (OS) (HR = 0.72, 95% CI: 0.55–0.95) and on disease free survival (DFS) (HR = 0.65, CI: 0.50–0.85). Adjuvant chemotherapy was superior to surgery alone based on OS and disease free survival (CLASSIC study HR = 0.72, CI: 0.52–1 and HR = 0.56, CI: 0.44–0.72, respectively). Adjuvant radiochemotherapy was superior to surgery alone (HR = 1.35, 95% CI: 1.09–1.66; P = 0.005).

Conclusion

A face‐to‐face comparison of perioperative chemotherapy versus adjuvant chemotherapy versus chemoradiotherapy is necessary.

Optimising Multimodality Treatment of Resectable Oesophago-Gastric Adenocarcinoma

Simple Summary

Oesophageal (food pipe) and stomach cancers are amongst the hard-to-treat cancers that result in significant illness and deaths around the globe. Over the last few decades, there has been remarkable progress in the treatment of these cancers as a result of advances in diagnosis, surgical techniques, systemic therapy and radiotherapy. However, even if caught in the early stages, most patients with these cancers will unfortunately have their cancers come back, usually becoming widespread and difficult to treat. Therefore, optimising the early treatment strategy of these cancers is essential to improve the outcome and reduce the risk of recurrence. There are currently various geographically influenced standard of care management practices of early stomach and oesophageal cancers, ranging from using chemotherapy before and after surgery to the use of combined chemoradiotherapy before surgery and more recently the use of immunotherapy after surgery. However, it is not very clear if one strategy is significantly better than the others and there are some ongoing studies aiming to directly compare these treatment options. In addition, our understanding of the molecular and genetic features of these cancers can help improve our clinical practice and inform our choice of the best treatment strategy for the individual patient.

Abstract

Oesophago–gastric adenocarcinoma remains a leading cause of cancer-related morbidity and mortality worldwide. Although there has been an enormous progress in the multimodality management of resectable oesophago–gastric adenocarcinoma, most patients still develop a recurrent disease that eventually becomes resistant to systemic therapy. Currently, there is no global consensus on the optimal multimodality approach and there are variations in accepted standards of care, ranging from preoperative chemoradiation to perioperative chemotherapy and, more recently, adjuvant immune checkpoint inhibitors. Ongoing clinical trials are aimed to directly compare multimodal treatment options as well as the additional benefit of targeted therapies and immunotherapies. Furthermore, our understanding of the molecular and genetic features of oesophago–gastric cancer has improved significantly over the last decade and these data may help inform the best approach for the individual patient, utilising biomarker selection and precision medicine.

Can the tumor-agnostic evaluation of MSI/MMR status be the common denominator for the immunotherapy treatment of patients with several solid tumors?

Alterations in short-repetitive DNA sequences, known as microsatellite instability (MSI), can reflect deficiencies in Mismatch Repair (MMR) system which represents a major player in DNA integrity maintenance. The incidence of MSI-H/dMMR has been shown to be variable depending on the tumor type. Several studies confirmed that dMMR/MSI status, although less frequent than PD-L1 expression, may better predict response to immune-checkpoint inhibitors (ICIs) in patients with solid tumors. In October 2016, the FDA granted pembrolizumab as breakthrough therapy for the treatment of non-CRC, MSI-H/dMMR tumors, providing, for the first time, a tumor-agnostic indication. In the next future, the tissue-agnostic evaluation of MSI-H/dMMR could become the common denominator for the immunotherapy treatment of patients with different advanced solid tumors, in order to select patient subgroups which may benefit from this therapy. In this Review we provided an overview of the main clinical studies describing the association between MSI-H/dMMR tumors and immunotherapy response.

Biomarker evaluation in radically resectable locally advanced gastric cancer treated with neoadjuvant chemotherapy: an evidence reappraisal

Neoadjuvant chemotherapy (NAC) significantly improved the prognosis of patients with locally advanced resectable gastric cancer but, despite important progresses, relapse-related death remains a major challenge. Therefore, it appears crucial to understand which patients will benefit from peri-operative treatment. Biomarkers such as human epidermal growth factor receptor-2 (HER2), microsatellite instability (MSI), and Epstein-Barr Virus (EBV) have been widely studied; however, they do not yet guide the choice of perioperative treatment in clinical practice. We performed a narrative review, including 23 studies, addressing the value of tissue- or blood-based biomarkers in the neoadjuvant setting. Ten studies (43.5%) were prospective, and more than half were conducted in East-Asia. Biomarkers were evaluated only post-NAC (on surgical samples or blood) in seven studies (30.4%), only pre-NAC (on endoscopic specimens or blood) in 10 studies (43.5%), and both pre- and post-NAC (26.1%) in six studies. Among the high variety of investigated biomarkers, some of these including MSI-H or enzymatic profile (as TS, UGT1A1, MTHFR, ERCC or XRCC) showed promising results and deserve to be assessed in methodologically sound clinical trials. The identification of molecular biomarkers in patients treated with NAC for locally advanced resectable gastric or EGJ cancer remains crucial.

The Chinese Society of Clinical Oncology (CSCO): Clinical guidelines for the diagnosis and treatment of gastric cancer, 2021

There exist differences in the epidemiological characteristics, clinicopathological features, tumor biological characteristics, treatment patterns, and drug selections between gastric cancer patients from the Eastern and Western countries. The Chinese Society of Clinical Oncology (CSCO) has organized a panel of senior experts specializing in all sub-specialties of gastric cancer to compile a clinical guideline for the diagnosis and treatment of gastric cancer since 2016 and renews it annually. Taking into account regional differences, giving full consideration to the accessibility of diagnosis and treatment resources, these experts have conducted expert consensus judgment on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes in China. The 2021 CSCO Clinical Practice Guidelines for Gastric Cancer covers the diagnosis, treatment, follow-up, and screening of gastric cancer. Based on the 2020 version of the CSCO Chinese Gastric Cancer guidelines, this updated guideline integrates the results of major clinical studies from China and overseas for the past year, focused on the inclusion of research data from the Chinese population for more personalized and clinically relevant recommendations. For the comprehensive treatment of non-metastatic gastric cancer, attentions were paid to neoadjuvant treatment. The value of perioperative chemotherapy is gradually becoming clearer and its recommendation level has been updated. For the comprehensive treatment of metastatic gastric cancer, recommendations for immunotherapy were included, and immune checkpoint inhibitors from third-line to the first-line of treatment for different patient groups with detailed notes are provided.

Multidisciplinary treatment strategy for locally advanced gastric cancer: A systematic review

BACKGROUND

Multidisciplinary management of patients with locally advanced gastric cancer (LAGC) remains unstandardized worldwide. We performed a systemic review to summarize the advancements, regional differences, and current recommended multidisciplinary treatment strategies for LAGC.

METHODS

Eligible studies were identified through a comprehensive search of PubMed, Web of Science, Cochrane Library databases and Embase. Phase 3 randomized controlled trials which investigated survival of patients with LAGC who underwent gastrectomy with pre-/perioperative, postoperative chemotherapy, or chemoradiotherapy were included.

RESULTS

In total, we identified 11 studies of pre-/perioperative chemotherapy, 38 of postoperative chemotherapy, and 14 of chemoradiotherapy. In Europe and the USA, the current standard of care is perioperative chemotherapy for patients with LAGC using the regimen of 5-FU, folinic acid, oxaliplatin and docetaxel (FLOT). In Eastern Asia, upfront gastrectomy and postoperative chemotherapy is commonly used. The S-1 monotherapy or a regimen of capecitabine and oxaliplatin (CapOx) are used for patients with stage II disease, and the CapOx regimen or the S-1 plus docetaxel regimen are recommended for those with stage III Gastric cancer (GC). The addition of postoperative radiotherapy to peri- or postoperative chemotherapy is currently not recommended. Additionally, clinical trials testing targeted therapy and immunotherapy are increasingly performed worldwide.

CONCLUSIONS

Recent clinical trials showed a survival benefit of peri-over postoperative chemotherapy and chemoradiotherapy. As such, this strategy may have a potential as a global standard for patients with LAGC. Outcome of the ongoing clinical trials is expected to establish the global standard of multidisciplinary treatment strategy in patients with LAGC.

Neoadjuvant and adjuvant multimodality therapies in resectable esophagogastric adenocarcinoma

Introduction: Gastric and esophageal adenocarcinoma is a leading cause of cancer-related death globally. Surgery is the cornerstone modality for cure where feasible. Clinical studies over the past two decades have provided evidence for the use of perioperative chemotherapy and chemoradiotherapy to improve patient outcomes. However, there remains no global consensus in the optimal use of these therapies.Areas covered: In this review, the authors summarize the latest evidence for perioperative multimodality therapy in resectable esophagogastric adenocarcinoma including the use of combination chemotherapy and targeted therapy containing regimens. In addition, the authors discuss some of the clinical and molecular biomarkers, such as PET imaging and microsatellite instability which can inform future practice and further clinical investigation.Expert opinion: A multimodal approach has been proven to improve survival outcomes over surgery alone. Whilst there is no global standard of care for multi-modality therapies in resectable OG cancer, clinical trials are refining the use of chemotherapy and radiotherapy in the neoadjuvant and adjuvant settings. Further investigation is on-going to further optimize therapy and the integration of molecular targeted agents.

CMPK1 Regulated by miR-130b Attenuates Response to 5-FU Treatment in Gastric Cancer

Gastric cancer (GC) remains a major world-wide challenge, especially in Asian countries. Chemotherapy with 5-fluorouracil (5-FU) and cisplatin is used as the first-line treatment and development of chemoresistance is a major cause of progression. UMP/CMP kinase is responsible for the phosphorylation of the ribonucleotide metabolite 5-fluoro-5′-monophosphate (FUMP) in 5-FU metabolic process, and recognized as a key step in the conversion of 5-FU to cytotoxic metabolites. Our bioinformatics analysis and molecular experiments demonstrated that high expression of CMPK1 was associated with prolonged survival and response to 5-FU treatment in GC samples. Further analysis demonstrated that miR-130b as a key epigenetic regulator of CMPK1, and miR-130b-mediated attenuation of CMPK1 resulted in resistance of gastric cancer cells to DNA damage and cell death after treatment with 5-FU. Rescue experiments with augmented CMPK1 expression abolished the effect of miR-130b demonstrating the key function of this miRNA in this pathway. Thus, this newly identified miR-130b-CMPK1 axis suggests a potentially new chemotherapeutic strategy for improved response to 5-FU therapy.

Enhancing the chemotherapy effect of Apatinib on gastric cancer by co-treating with salidroside to reprogram the tumor hypoxia micro-environment and induce cell apoptosis

Hypoxic microenvironment commonly occurred in the solid tumors considerably decreases the chemosensitivity of cancer cells. Salidroside (Sal), the main active ingredient of Rhodiola rosea, was shown to be able of regulating the tumor hypoxia micro-environment and enhancing the chemotherapeutic efficacy of drug-resistant cancer. Therefore, in this study, the Sal was co-loaded with Apatinib (Apa) by the PLGA-based nanoparticles (NPs) to improve the chemosensitivity of gastric cancer cells. Additionally, to improve the drug delivery efficacy, the tumor-homing peptide (iVR1 peptides) was further decorated on the surface of NPs. The tumor targeting ability of the peptides-functionalized nanoparticles (iVR1-NPs-Apa/Sal) was evaluated by in vitro and in vivo experiments. As the obtained results revealed that the iVR1-NPs-Apa/Sal displayed excellent tumor affinity than the unmodified ones (NPs-Apa/Sal), which in turn resulted in more efficient of anti-proliferation of gastric cancer cells and anti-tumor effect in vivo. In addition, compared with the cells or tumor-bearing mice only treaded by monotherapy of Apa, the cells or mice received combinational treatment of Apa and Sal showed obvious lower rate of growth, invasion, and migration or tumor growth and progress. Underlying mechanisms were further investigated and it was revealed that the anti-gastric cancer effect of Apa was signally improved by Sal through down-regulation the proliferation factors and increase the pro-apoptotic genes, as well as reprograming the tumor hypoxia micro-environment. In a word, the study showed that the Sal was able of improving the chemosensitivity of gastric cancer to Apa and the iVR1-NPs-Apa/Sal was capable of realizing highly efficient of tumor-targeting drug delivery.

Towards Personalization in the Curative Treatment of Gastric Cancer

Gastric cancer is the fifth most common cancer worldwide and has a high mortality rate. In the last decades, treatment strategy has shifted from an exclusive surgical approach to a multidisciplinary strategy. Treatment options for patients with resectable gastric cancer as recommended by different worldwide guidelines, include perioperative chemotherapy, pre- or postoperative chemoradiotherapy and postoperative chemotherapy. Although gastric cancer is a heterogeneous disease with respect to patient-, tumor-, and molecular characteristics, the current standard of care is still according to a one-size-fits-all approach. In this review, we discuss the background of the different treatment strategies in resectable gastric cancer including the current standard, the specific role of radiotherapy, and describe the current areas of research and potential strategies for personalization of therapy.

Multimodality treatment for localized gastric cancer: state of the art and new insights

PURPOSE OF REVIEW

Surgery represents the only curative approach for resectable gastric cancer. However, rates of recurrence remain high. This review summarizes the state of the art and future perspectives regarding perioperative, neoadjuvant and adjuvant chemotherapy for localized gastric cancer with insights regarding precision medicine.

RECENT FINDINGS

Perioperative chemotherapy with FLOT has significantly improved outcomes for non-Asian patients with resectable gastric cancer, removing the role for anthracyclines. Preliminary results demonstrate that the perioperative approach is an option for Asian patients; however, long-term outcomes are awaited. For adjuvant treatment in Asian gastric cancer patients, S-1 as well as docetaxel may be a new treatment option. In this context, the right selection of patients is crucial. Among several biomarkers, microsatellite instability/mismatch repair deficiency has been linked with a lack of benefit from chemotherapy as well as better prognosis.

SUMMARY

Multimodality treatment represents the standard of care for resectable gastric cancer. Perioperative chemotherapy with FLOT is the standard treatment in western countries; in patients who are not suitable for triplet, a platinum-fluoropyrimidine doublet can be considered. In Asian countries, adjuvant chemotherapy based on fluoropyrimidine monotherapy or in association with oxaliplatin/docetaxel are options. Validation of prognostic and predictive biomarkers is needed in order to improve patient selection.

Association of high TUBB3 with resistance to adjuvant docetaxel-based chemotherapy in gastric cancer: translational study of ITACA-S

BACKGROUND

No predictive markers for chemotherapy activity have been validated in gastric cancer (GC). The potential value of class III β-tubulin (TUBB3) as biomarker for prognosis and resistance to taxane-based therapy was reported.

METHODS

We analyzed GC samples of patients enrolled in the Intergroup Trial of Adjuvant Chemotherapy in Adenocarcinoma of the Stomach (ITACA-S), a randomized adjuvant study comparing 5-fluorouracil/leucovorin (5-FU/LV) and docetaxel-based sequential chemotherapy. TUBB3 was quantitated by selected reaction monitoring mass spectrometry and patients were stratified using a threshold of 750 attomoles per microgram (amol/µg). Cox proportional modeling and Kaplan-Meier survival analysis were used to assess the impact of TUBB3 expression on overall survival (OS) and disease-free survival.

RESULTS

Patients with TUBB3 protein levels >750 and <750 amol/µg were 21.9% and 78.1%, respectively, and were well-balanced between treatment arms. TUBB3 protein levels were not prognostic. Whereas no survival differences according to the 2 arms were observed in the subgroup with low TUBB3 expression (5-year OS 47% vs 40%; p = 0.44), patients with high TUBB3 had a clinically meaningful poorer OS when receiving docetaxel-based versus 5-FU/LV chemotherapy (5-year OS 31% vs 54%; p = 0.09), with a statistically significant interaction between TUBB3 and treatment (p = 0.049).

CONCLUSIONS

The quantification of TUBB3 might be considered as a negative predictive biomarker of benefit from taxane-based therapy in GC. Studies are needed to evaluate its role in the neoadjuvant setting.

Adjuvant Chemotherapy in Microsatellite Instability-High Gastric Cancer

PURPOSE

Microsatellite instability (MSI) status may affect the efficacy of adjuvant chemotherapy in gastric cancer. In this study, the clinical characteristics of MSI-high (MSI-H) gastric cancer and the predictive value of MSI-H for adjuvant chemotherapy in large cohorts of gastric cancer patients were evaluated.

Material and Methods

This study consisted of two cohorts. Cohort 1 included gastric cancer patients who received curative resection with pathologic stage IB-IIIC. Cohort 2 included patients with MSI-H gastric cancer who received curative resection with pathologic stage II/III. MSI was examined using two mononucleotide markers and three dinucleotide markers.

RESULTS

Of 359 patients (cohort 1), 41 patients (11.4%) had MSI-H. MSI-H tumors were more frequently identified in older patients (p < 0.001), other histology than poorly cohesive, signet ring cell type (p=0.005), intestinal type (p=0.028), lower third tumor location (p=0.005), and absent perineural invasion (p=0.027). MSI-H status has a tendency of better disease-free survival (DFS) and overall survival (OS) in multivariable analyses (hazard ratio [HR], 0.4; p=0.059 and HR, 0.4; p=0.063, respectively). In the analysis of 162 MSI-H patients (cohort 2), adjuvant chemotherapy showed a significant benefit with respect to longer DFS and OS (p=0.047 and p=0.043, respectively). In multivariable analysis, adjuvant chemotherapy improved DFS (HR, 0.4; p=0.040).

CONCLUSION

MSI-H gastric cancer had distinct clinicopathologic findings. Even in MSI-H gastric cancer of retrospective cohort, adjuvant chemotherapy could show a survival benefit, which was in contrast to previous prospective studies and should be investigated in a further prospective trial.

Clinical Outcome in Patients with Carcinoma of the Esophagogastric Junction Treated with Neoadjuvant Radiochemotherapy or Perioperative Chemotherapy: A Two-Center Retrospective Analysis

BACKGROUND

Adenocarcinoma of the esophagogastric junction (AEG) is a rare but rising tumor entity in the Western world. Treatment is complex, as multimodality is key to optimal results. However, trials solely including AEG are rare, and the question if neoadjuvant radiochemotherapy (NRCT) or neoadjuvant/perioperative chemotherapy (NACT) is superior remains unanswered.

PATIENTS AND METHODS

Patients with AEG I-III treated between October 2010 and August 2019 at the Ordensklinikum Linz or the Kepler University Hospital were identified either from a monitored tumor registry or by chart review. Time-to-event data were analyzed by Kaplan-Meier product limit estimation. The Kruskal-Wallis test and Fisher's exact test were used for comparing continuous and categorical data, respectively.

RESULTS

A total of 85 patients (median age 63 years; median Charlson Comorbidity Index 3; 98.8% ECOG PS 0-1) were analyzed. Of these, 52 patients received NRCT (81% CROSS protocol) and 33 NACT (65% EOX and 35% FLOT protocol). There was a significantly higher pathological complete response rate in the NRCT group (30 vs. 12%; p = 0.010); distant relapse rates were higher in the NRCT group and local relapse rates were higher in the NACT group (both not significant). These differences, however, did not translate into a different disease-free survival (20 months; 95% CI: 13-34) or overall survival (44 months; 95% CI: 33-NA). Patients >65 years old had the same advantage from treatment as patients <65 years of age.

CONCLUSIONS

Although treatment of AEG is complex, the progress documented over the last centuries can be reproduced in our real-life setting. Data regarding the superiority of either type of neoadjuvant/perioperative treatment are sparse. We assume no difference between EOX-based NACT and NRCT.

Management of early-stage gastro-esophageal cancers: expert perspectives from the Australasian Gastrointestinal Trials Group (AGITG) with invited international faculty

Introduction: A multimodal approach in operable early-stage oesophago-gastric (OG) cancer has evolved in the last decade, leading to improvement in overall outcomes.Areas covered: A review of the published literature and conference abstracts was undertaken on the topic of optimal adjunctive chemotherapy or chemoradiotherapy in early-stage OG cancers. This review article focuses on the current evidence pertaining to neoadjuvant and perioperative strategies in curable OG cancers including the evolving landscape of immunotherapy and targeted drugs in this setting.Expert commentary: Adjunctive therapies in the form of preoperative chemo-radiotherapy (CRT) or chemotherapy and perioperative chemotherapy over surgery alone improve outcomes in patients with operable OG cancer. Although there are variations in practice around the world, a multi-disciplinary approach to patient care is of paramount importance. Immunotherapy and on treatment functional imaging are two examples of emerging strategies to improve the outcome for early-stage patients. A better understanding of the molecular biology of this disease may help overcome the problem of tumor heterogeneity and enable more rationally designed and targeted therapeutic interventions in the future.

Prognostic and Predictive Value of Microsatellite Instability, Inflammatory Reaction and PD-L1 in Gastric Cancer Patients Treated with Either Adjuvant 5-FU/LV or Sequential FOLFIRI Followed by Cisplatin and Docetaxel: A Translational Analysis from the ITACA-S Trial

BACKGROUND

Patients with high microsatellite instability (MSI) gastric cancer (GC) show improved survival and no benefit or harm from adjuvant and/or perioperative chemotherapy. The role of immune microenvironment in GC is largely unknown.

MATERIALS AND METHODS

In the present study, 256 tumor tissue blocks were centrally collected from patients enrolled in ITACA-S, a randomized adjuvant trial of 5-FU/LV versus sequential FOLFIRI and cisplatin-docetaxel. MSI status was assessed by multiplex PCR, inflammatory reaction by H&E morphological assessment, and programmed death-ligand 1 (PD-L1) expression by immunohistochemistry.

RESULTS

Overall, 9% patients had MSI-high tumors, 23% had high inflammatory reaction, 11% had tumor PD-L1 ≥ 1%, and 11% had stromal PD-L1 ≥ 1%. A significant association with disease-free survival (DFS) and overall survival (OS) was found for MSI-high (hazard ratio [HR], 0.43; p = .02; HR, 0.40; p = .02) and high inflammatory reaction (HR, 0.55; p = .010; HR, 0.53; p = .008) but not for PD-L1. At multivariable analysis, only MSI showed an independent association with both DFS (p = .02) and OS (p = .01), whereas inflammatory reaction showed an independent association only with OS (p = .04). Patients with tumor PD-L1 ≥ 1% had a significantly longer DFS in sequential chemotherapy than in than 5-FU/LV arm (interaction p = .04) and a trend for OS (interaction p = .12).

CONCLUSION

Our data suggest that MSI status could be a useful prognostic biomarker in patients with radically resected stage II-III GC and should be used as stratification factor in future trials. Tumor PD-L1 ≥ 1% should be further investigated as a potential predictor of benefit from intensive chemotherapy.

IMPLICATIONS FOR PRACTICE

In this post hoc analysis of patients with radically resected gastric cancer randomized to an intensive sequential chemotherapy regimen versus 5-FU/LV monotherapy as adjuvant treatment in the ITACA-S trial, MSI-high status was independently associated with better disease-free survival and overall survival (OS) and inflammatory reaction was independently associated with better OS. Moreover, tumor PD-L1 expression ≥1% was associated with greater benefit from intensive sequential chemotherapy compared with 5-fluorouracil plus leucovorin (5-FU/LV), whereas PD-L1 expression <1% was not, conditioning a statistically significant interaction between such biomarker and treatment arms. The meta-analysis of individual patients' data from available studies could yield data on the role of MSI status that could inform clinical decisions.

ADJUVANT CHEMORADIOTHERAPY AFTER SUBTOTAL OR TOTAL GASTRECTOMY AND D2 LIMPHADENECTOMY INCREASES SURVIVAL IN ADVANCED GASTRIC CANCER?

BACKGROUND

The treatment of advanced gastric cancer with curative intent is essentially surgical and chemoradiotherapy is indicated as neo or adjuvant to control the disease and prolong survival.

AIM

To assess the survival of patients undergoing subtotal or total gastrectomy with D2 lymphadenectomy followed by adjuvant chemoradiotherapy.

METHODS

Were retrospectively analyzed 87 gastrectomized patients with advanced gastric adenocarcinoma, considered stages IB to IIIC and submitted to adjuvant chemoradiotherapy (protocol INT 0116). Tumors of the esophagogastric junction, with peritoneal implants, distant metastases, and those that had a compromised surgical margin or early death after surgery were excluded. They were separated according to the extention of the gastrectomy and analyzed for tumor site and histopathology, lymph node invasion, staging, morbidity and survival.

RESULTS

The total number of patients who successfully completed the adjuvant treatment was 45 (51.7%). Those who started treatment and discontinued due to toxicity, tumor-related worsening, or loss of follow-up were 10 (11.5%) and reported as incomplete adjuvant. The number of patients who refused or did not start adjuvant treatment was 33 (48.3%). Subtotal gastrectomy was indicated in 60 (68.9%) and total in 27 (31.1%) and this had a shorter survival. The mean resected lymph nodes was 30.8. Staging and number of lymph nodes affected were predictors of worse survival and the more advanced the tumor. Patients undergoing adjuvant therapy with complete chemoradiotherapy showed a longer survival when compared to those who did it incompletely or underwent exclusive surgery. On the other hand, comparing the T4b (IIIB + IIIC) staging patients who had complete adjuvance with those who underwent the exclusive operation or who did not complete the adjuvant, there was a significant difference in survival.

CONCLUSION

Adjuvant chemoradiotherapy presents survival gain for T4b patients undergoing surgical treatment with curative intent.

Gastroesophageal cancer: Navigating the immune and genetic terrain to improve clinical outcomes

Recent advances in our understanding of the molecular biology of gastric and oesophageal cancers have shown that gastroesophageal adenocarcinoma should be considered as one disease spectrum. Clinical management of these cancers is challenging, with poor outcomes in both early and late disease settings. Certain molecular subsets of gastroesophageal adenocarcinoma demonstrate features that suggest immunotherapy could be an effective treatment. Immunogenetic markers, including mismatch repair deficiency, PD-L1 status and tumour infiltrating lymphocytes influence overall prognosis. They may also determine the response to adjuvant and neoadjuvant conventional chemotherapy. Initial results from immunotherapy trials for gastroesophageal cancer have however been mixed, with poor overall responses in the first- and second-line settings. This review aims to discuss how better understanding of these immune and genetic interactions may lead to better selection of patients for conventional and immune based therapies, and therefore improve patient outcomes. We also discuss the challenges in implementing this new understanding in routine practice, and the current limitations of immune based treatments for gastroesophageal cancer.

Individual Patient Data Meta-Analysis of the Value of Microsatellite Instability As a Biomarker in Gastric Cancer

PURPOSE

In the CLASSIC and MAGIC trials, microsatellite instability (MSI)-high status was a favorable prognostic and potential negative predictive factor for neoadjuvant/adjuvant chemotherapy in resectable gastric cancer (GC). Given the low prevalence of MSI-high status in GC and its association with other positive prognostic variables, large data sets are needed to draw robust evidence of its prognostic/predictive value.

PATIENTS AND METHODS

We performed a multinational, individual-patient-data meta-analysis of the prognostic/predictive role of MSI in patients with resectable GC enrolled in the MAGIC, CLASSIC, ARTIST, and ITACA-S trials. Prognostic analyses used multivariable Cox models (MVM). The predictive role of MSI was assessed both in an all-comer population and in MAGIC and CLASSIC trials by MVM testing of the interaction of treatment (chemotherapy plus surgery v surgery) with MSI.

RESULTS

MSI status was available for 1,556 patients: 121 (7.8%) had MSI-high status; 576 were European, and 980 were Asian. In MSI-high versus MSI-low/microsatellite stable (MSS) comparisons, the 5-year disease-free survival (DFS) was 71.8% (95% CI, 63.8% to 80.7%) versus 52.3% (95% CI, 49.7% to 55.1%); the 5-year overall survival (OS) was 77.5% (95% CI, 70.0% to 85.8%) versus 59.3% (95% CI, 56.6% to 62.1%). In MVM, MSI was associated with longer DFS (hazard ratio [HR], 1.88; 95% CI, 1.28 to 2.76; P < .001) and OS (HR, 1.78; 95% CI, 1.17 to 2.73; P = .008), as were pT, pN, ethnicity, and treatment. Patients with MSI-low/MSS GC benefitted from chemotherapy plus surgery: the 5-year DFS compared with surgery only was 57% versus 41% (HR, 0.65; 95% CI, 0.53 to 0.79), and the 5-year OS was 62% versus 53% (HR, 0.75; 95% CI, 0.60 to 0.94). Conversely, those with MSI-high GC did not: the 5-year DFS was 70% versus 77% (HR, 1.27; 95% CI, 0.53 to 3.04), and the 5-year OS was 75% versus 83% (HR, 1.50; 95% CI, 0.55 to 4.12).

CONCLUSION

In patients with resectable primary GC, MSI is a robust prognostic marker that should be adopted as a stratification factor by clinical trials. Chemotherapy omission and/or immune checkpoint blockade should be investigated prospectively in MSI-high GCs according to clinically and pathologically defined risk of relapse.

Gastric cancer: Translating novels concepts into clinical practice

The overall 5-year survival of gastric cancer (GC) has change only little in the last decades and it remains the fifth leading cause of cancer-related death worldwide. However, in the past few years a more effective combination chemotherapy has raised the bar of curability of about 10% in resectable disease. Morever, a deeper knowledge of GC biology have unveiled biomarkers to help personalize adjunctive treatments in patients candidate to surgery. Despite a plateau in efficacy of fist-line treatment, incremental survival advantages have been recorded in unresectable advanced disease. The growing number of effective drugs in second and later lines along with a more judicious delivery of cytotoxics and early supportive interventions have enabled more patients to proceed beyond first-line. The continuum of care has become a reality in a considerable proportion of patients that offer opportunities to improve outcomes. Finally, the advent of the immune checkpoint inhibitors has brought great expectations in molecularly-defined subset of patients. This Review summarizes the state-of-the art in the management of GC together with novel concepts that have entered clinical development with the potential of change practice in the foreseeable future.

COMplot, A Graphical Presentation of Complication Profiles and Adverse Effects for the Curative Treatment of Gastric Cancer: A Systematic Review and Meta-Analysis

Background: For the curative treatment of gastric cancer, several neoadjuvant, and adjuvant treatment-regimens are available which have shown to improve overall survival. No overview is available regarding toxicity and surgery related outcomes. Our aim was to construct a novel graphical method concerning adverse events (AEs) associated with multimodality treatment and perform a meta-analysis to compare different clinically relevant cytotoxic regimens with each other.

Methods: The PubMed, EMBASE, CENTRAL, and ASCO/ESMO databases were searched up to May 2019 for randomized controlled trials investigating curative treatment regimens for gastric cancer. To construct single and bidirectional bar-charts (COMplots), grade 1–2 and grade 3–5 AEs were extracted per cytotoxic regimen. For surgery-related outcomes a pre-specified set of complications was used. Thereafter, treatment-arms comparing the same regimens were combined in a single-arm random-effects meta-analysis and pooled-proportions were calculated with 95% confidence-intervals. Comparative meta-analyses were performed based on clinical relevance and compound similarity.

Results: In total 16 RCTs (n = 4,526 patients) were included investigating pre-operative-therapy and 39 RCTs investigating adjuvant-therapy (n = 13,732 patients). Pre-operative COMplots were created for among others; 5-fluorouracil/leucovorin-oxaliplatin-docetaxel (FLOT), epirubicin-cisplatin-fluoropyrimidine (ECF), cisplatin-fluoropyrimidine (CF), and oxaliplatin-fluoropyrimidine (FOx). Pre-operative FLOT showed a minor increase in grade 1–2 and grade 3–4 AEs compared to pre-operative ECF, CF, and FOx. A pooled analysis of patients who had received pre-operative therapy compared to patients who underwent direct surgery did not reveal any significant difference in surgery related morbidity/mortality. When we compared three commonly used adjuvant regimens; S-1 had the lowest amount of grade 3–4 AEs compared to capecitabine with oxaliplatin (CAPOX) and 5-FU with radiotherapy (5-FU+RT).

Conclusion: COMplot provides a novel tool to visualize and compare treatment related AEs for gastric cancer. Based on our comparisons, pre-operative FLOT had a manageable toxicity profile compared to other pre-operative doublet or triplet regimens. We found no evidence indicating surgical outcomes might be hampered by pre-operative therapy. Adjuvant S-1 had a more favorable toxicity profile compared to CAPOX and 5-FU+RT.

Multimodality management of locally advanced gastric cancer-the timing and extent of surgery

The optimal treatment for patients with locally advanced gastric adenocarcinoma is multimodal. Surgery is the cornerstone of therapeutic strategies with curative intent. The addition of chemotherapy or chemoradiation decreases rate of recurrence and prolongs survival. Guidelines differ between countries and there is no universal standard of care. Modern studies of patients with locally advanced gastric cancer showed that adjuvant chemotherapy improves survival over surgery alone in Asia. These studies could not be replicated in Europe. Peri-operative chemotherapy strategies, conversely, have been effective in Europe for improving overall and disease free survival. Adjuvant chemoradiation has also demonstrated improved survival when compared to surgery alone, but studies comparing chemotherapy with chemoradiation have not shown significant difference. Trials are ongoing to examine the role of chemoradiation in a neoadjuvant fashion. A D2 extent of lymphadenectomy improves cancer related survival for those who do not undergo distal pancreatectomy/splenectomy. Survival is also associated not only with the extent but also the number of lymph nodes examined. There are ongoing trials related to immunotherapy and targeted therapies, which may also impact or change the treatment paradigm for locally advanced gastric cancer.

Impact of perioperative treatment on survival of resectable gastric cancer patients after D2 lymphadenectomy: a single European centre propensity score matching analysis

Background To determine the effects of perioperative treatment of gastric cancer patients, we conducted an analysis with propensity score matched patient groups to determine the role of perioperative chemotherapy in patients after D2 lymphadenectomy. Patients and methods From our database of 1563 patients, 482 patients were selected with propensity score matching and divided into two balanced groups: 241 patients in the surgery only group and 241 patients in the perioperative group. The long-term results of treatment were compared between the two groups. Results Most of the included patients received radio-chemotherapy with capecitabine (n = 111; 46%) and perioperative chemotherapy with epirubicin, oxalliplatin and capecitabine (n = 91; 37.7%). 92.9% of the patients received a D2 lymph node dissection. Perioperative morbidity was similar between surgery only (18.3%) and perioperative treatment groups (20.7%) (p = 0.537). The perioperative mortality was not influenced by perioperative treatment. A pathological response was observed in 12.5% of patients. The overall 5-year and median survivals were significantly higher in the perioperative treatment group (50.5%; 51.7 moths) compared to surgery only group (41.8%; 34.9 months; p = 0.038). The subgroup analysis revealed that only patients with the TNM stages T3 (p = 0.028), N2 (p = 0.009), N3b (p = 0.043), and UICC stages IIIb (p = 0.003) and IIIc (p = 0.03) significantly benefit from perioperative treatment. Conclusions Perioperative treatment in radically resected gastric cancer patients after D2 lymphadenectomy was beneficial in stages IIIb and IIIc. The effects of perioperative treatment in lower stages could be negated by the effects of the radical surgery in lower stages and in higher stages by the biology of the disease.

Prognostic and Predictive Factors for the Curative Treatment of Esophageal and Gastric Cancer in Randomized Controlled Trials: A Systematic Review and Meta-Analysis

BACKGROUND

An overview of promising prognostic variables and predictive subgroups concerning the curative treatment of esophageal and gastric cancer from randomized controlled trials (RCTs) is lacking. Therefore, we conducted a systematic review and meta-analysis.

METHODS

PubMed, EMBASE, CENTRAL, and ASCO/ESMO conferences were searched up to March 2019 for RCTs on the curative treatment of esophageal or gastric cancer with data on prognostic and/or predictive factors for overall survival. Prognostic factors were deemed potentially clinically relevant according to the following criteria; (1) statistically significant (p < 0.05) in a multivariate analysis, (2) reported in at least 250 patients, and (3) p < 0.05, in ≥ 33% of the total number of patients in RCTs reporting this factor. Predictive factors were potentially clinically-relevant if (1) the p-value for interaction between subgroups was <0.20 and (2) the hazard ratio in one of the subgroups was significant (p < 0.05).

RESULTS

For gastric cancer, 39 RCTs were identified (n = 13,530 patients) and, for esophageal cancer, 33 RCTs were identified (n = 8618 patients). In total, we identified 23 potentially clinically relevant prognostic factors for gastric cancer and 16 for esophageal cancer. There were 15 potentially clinically relevant predictive factors for gastric cancer and 10 for esophageal cancer.

CONCLUSION

The identified prognostic and predictive factors can be included and analyzed in future RCTs and be of guidance for nomograms. Further validation should be performed in large patient cohorts.

The Efficacy and Safety of (Neo)Adjuvant Therapy for Gastric Cancer: A Network Meta-analysis

Background: Alternatives in treatment-strategies exist for resectable gastric cancer. Our aims were: (1) to assess the benefit of perioperative, neoadjuvant and adjuvant treatment-strategies and (2) to determine the optimal adjuvant regimen for gastric cancer treated with curative intent. Methods: PubMed, EMBASE, CENTRAL, and ASCO/ESMO conferences were searched up to August 2017 for randomized-controlled-trials on the curative treatment of resectable gastric cancer. We performed two network-meta-analyses (NMA). NMA-1 compared perioperative, neoadjuvant and adjuvant strategies only if there was a direct comparison. NMA-2 compared different adjuvant chemo(radio)therapy regimens, after curative resection. Overall-survival (OS) and disease-free-survival (DFS) were analyzed using random-effects NMA on the hazard ratio (HR)-scale and calculated as combined HRs and 95% credible intervals (95% CrIs). Results: NMA-1 consisted of 9 direct comparisons between strategies for OS (14 studies, n = 4187 patients). NMA-2 consisted of 16 direct comparisons between adjuvant chemotherapy/chemoradiotherapy regimens for OS (37 studies, n = 10,761) and 14 for DFS (30 studies, n = 9714 patients). Compared to taxane-based-perioperative-chemotherapy, surgery-alone (HR = 0.58, 95% CrI = 0.38⁻0.91) and perioperative-chemotherapy regimens without a taxane (HR = 0.79, 95% CrI = 0.58⁻1.15) were inferior in OS. After curative-resection, the doublet oxaliplatin-fluoropyrimidine (for one-year) was the most efficacious adjuvant regimen in OS (HR = 0.47, 95% CrI = 0.28⁻0.80). Conclusions: For resectable gastric cancer, (1) taxane-based perioperative-chemotherapy was the most promising treatment strategy; and (2) adjuvant oxaliplatin-fluoropyrimidine was the most promising regimen after curative resection. More research is warranted to confirm or reproach these findings.

Cutting-edge evidence of adjuvant treatments for gastric cancer

In recent decades, adjuvant therapy has secured a firm position in the treatment of gastric cancer by improving patient prognosis. Currently, standard therapy varies between East Asia, Europe and North America due to heterogeneities of the tumor, race, medical environment and/or surgical procedure. Although adjuvant strategies, proved effective in each region and implemented to clinical practice, certain patient populations with advanced gastric cancer show recurrence and a fatal prognosis. The development of a universal adjuvant therapy with a high efficacy and acceptable adverse events or with less toxicity and non-inferiority seems to have become urgent and imperative. Areas covered: In this review, we aimed to summarize the current knowledge regarding adjuvant therapies for gastric cancer, including chemotherapy, chemoradiotherapy and molecular targeted therapy, based on clinical trials and to introduce the pivotal ongoing phase III trials. Expert commentary: The efficacy of adjuvant therapy to prevent recurrence remains insufficient although several trials have shown a significant benefit in patients with localized advanced gastric cancer. The development of more effective and universal multimodal adjuvant therapy is required.

Recent advances in the management of gastric adenocarcinoma patients

Gastric adenocarcinoma (GAC) is one of the most aggressive malignancies and has a dismal prognosis. Therefore, multimodality therapies to include surgery, chemotherapy, targeted therapy, immunotherapy, and radiation therapy are needed to provide advantage. For locally advanced GAC (>cT1B), the emerging strategies have included preoperative chemotherapy, postoperative adjuvant chemotherapy, and (occasionally) postoperative chemoradiation in various regions. Several novel therapies have been assessed in clinical trials, but only trastuzumab and ramucirumab (alone and in combination with paclitaxel) have shown overall survival advantage. Pembrolizumab has been approved by the US Food and Drug Administration on the basis of response rate only for patients with microsatellite instability (MSI-H) or if PD-L1 expression is positive (≥1% labeling index in tumor/immune cells in the presence of at least 100 tumor cells in the specimen). Nivolumab has been approved in Japan on the basis of a randomized trial showing significant survival advantage for patients who received nivolumab compared with placebo in the third or later lines of therapy. The cure rate of patients with localized GAC in the West is only about 40% and that for metastatic cancer is very poor (only 2-3%). At this stage, much more target discovery is needed through molecular profiling. Personalized therapy of patients with GAC remains a challenge.

Gastric cancer: French intergroup clinical practice guidelines for diagnosis, treatments and follow-up (SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO)

INTRODUCTION

This document is a summary of the French Intergroup guidelines regarding the management of gastric cancer published in October 2016, available on the website of the French Society of Gastroenterology (SNFGE) (www.tncd.org), updated in October 2017.

METHODS

This collaborative work was realized under the auspices of several French medical societies involved in management of gastric cancer. Recommendations are graded in three categories (A-C), according to the amount of evidence found in the literature until July 2017.

RESULTS

There are several known risk factors for gastric cancer, including Helicobacter pylori and genetic predispositions, both requiring a specific screening for patients and their relatives. The diagnosis and staging evaluation are essentially based on gastroscopy plus biopsies and computed tomography scan. The endoscopic ultrasonography can be used for superficial tumors in case of discussion for endoscopic resection (T1N0). For local disease (N+ and/or T > T1), the strategic therapy is based on surgery associated with perioperative chemotherapy. In the absence of preoperative treatment (for any raison), the postoperative chemoradiotherapy (or chemotherapy) should be discussed for patients with stage II or III tumor. For metastatic disease, the treatment is based on "palliative" chemotherapy consisting in a doublet or triplet regimens depending of age, performance status and HER2 tumor status. For patients with limited metastatic disease, surgical resection could be discussed in multidisciplinary meeting in case of stable disease after chemotherapy.

CONCLUSION

These guidelines in gastric cancer are done to help decision for daily clinical practice. These recommendations are permanently being reviewed. Each individual case must be discussed within a multidisciplinary team.

Multimodal treatment in locally advanced gastric cancer

According to the data of the GLOBOCAN-network of the World Health Organization, there were 952,000 (6.8% of the total) new cases of gastric cancer in 2012, making it the fifth most common malignancy in the world. It represents a substantive change since the very first estimates in 1975 when stomach cancer was the most common neoplasm. More than 70% of cases (677,000 cases) occur in developing countries, and half the world total occurs in Eastern Asia, mainly in China. Gastric cancer is the third leading cause of cancer death in both sexes worldwide (Globocan, Estimated cancer incidence, mortality and prevalence worldwide in 2012, http://globocan.iarc.fr , 2012). Annually, worldwide 723,000 patients die of this tumor entity. Interestingly, a strong change in incidence rates in relation to the anatomical-topographic localization of the primary tumors in the stomach and esophagus has been experienced. While the frequency of proximal gastric carcinoma and adenocarcinoma of the cardiac and subcardiac region in Europe and North America has been constantly rising, distal gastric carcinomas have become less common (Torre et al. in JAMA 65:87-108, 2015). Furthermore, the relative incidence of esophageal adenocarcinoma (mostly localized in the distal esophagus) has strongly increased (Jemal et al. in JAMA 58:71-96, 2008; Crew and Neugut 31:450-464, 2004; Pohl and Welch 97:142-146, 2005).

Optimal management of resected gastric cancer

Although advances in medical treatment for gastric cancer (GC) have been made, surgery remains the mainstay of cure for patients with localized disease. Improvement in surgical modalities leads to increased chance of cure for resected patients, but a non-negligible number of patients eventually relapse. On this basis, it has been hypothesized that the addition of complementary systemic or local treatments (such as chemotherapy and radiotherapy) could help in improving patients' survival by reducing the risk of recurrence. Several studies have tried to identify the best approach in localized GC: some of them have assessed the role of perioperative chemotherapy [CT] with different drug combinations, while others have focused on the benefit obtained by addition of radiotherapy, whose role is still under investigation. In particular, the role of chemoradiotherapy, both in adjuvant and neoadjuvant settings, is still uncertain. In the last few years, several clinicopathological and molecular factors have been investigated and identified as potential prognostic markers in GC. Many of these factors could have influenced the outcome of patients receiving combined treatments in the abovementioned studies. Patients have not been generally distinguished by the site of disease (esophageal, gastric and junctional cancers) and surgical approach, making data difficult to be interpreted. The purpose of this review was to shed light on these highly controversial topics.

Locally advanced gastro-oesophageal cancer: Recent therapeutic advances and research directions

Gastric (GC) and gastro-oesophageal (GOJC) adenocarcinomas are often considered as a single entity, even though differences exist in epidemiology, clinical presentation, molecular biology and treatment options. Locally advanced, resectable disease represents a particularly challenging scenario, as many critical issues need to be addressed. In both GC and GOJC among Western countries, systemic chemotherapy demonstrated the greatest benefit when administered before and after surgery and perioperative chemotherapy has been set as a standard in this setting. Nonetheless, multiple chemotherapy regimens have been tested and direct comparisons have been only recently presented. Adjuvant chemoradiotherapy is an option as well, but several trials have questioned its role when more effective combination regimens are used. With regards to GOJC, preoperative chemoradiotherapy is an alternative to perioperative chemotherapy, as it is associated with higher pathologic responses and a different toxicity profile: however, a definitive comparison with chemotherapy is ongoing. Herein, we review the current options for the treatment of resectable GC and GOJC and the main open questions in the management of these patients, trying to depict an update of the available algorithms for everyday practice. Moreover, we summarize the design and preliminary results of the randomized trials in progress that will hopefully give definitive answers to the most debated issues in the field.

Refining the management of resectable esophagogastric cancer: FLOT4, CRITICS, OE05, MAGIC-B and the promise of molecular classification

The multidisciplinary management of locoregional esophagogastric cancers (GCs) has evolved significantly over the past two decades. While perioperative chemotherapy, adjuvant chemotherapy, and postoperative chemotherapy with chemoradiation (CRT) have demonstrated improved survival when compared to surgery alone, there is no universal standard for resectable gastroesophageal cancer. Current global management patterns vary by geographic region, partly related to phase III data originating from each global region. Herein we detail the landmark phase III trials that support the various multimodality treatment paradigms in resectable GC, with particular focus on findings from more recent phase III gastroesophageal cancer trials including FLOT4, MAGIC-B, OE05, and CRITICS. We highlight important ongoing and future approaches including the potential of molecular subtyping, predictive biomarkers, and immunotherapy as avenues to further improve outcomes in resectable gastroesophageal cancer.