Cetuximab plus oxaliplatin/leucovorin/5-fluorouracil in first-line metastatic gastric cancer: a phase II study of the Arbeitsgemeinschaft Internistische Onkologie (AIO)

Effect of cetuximab plus FOLFOX4 regimen on clinical outcomes in advanced gastric carcinoma patients receiving evidence-based care

BACKGROUND

Although chemotherapy is effective for treating advanced gastric carcinoma (aGC), it may lead to an adverse prognosis. Establishing a highly effective and low-toxicity chemotherapy regimen is necessary for improving efficacy and outcomes in aGC patients.

AIM

To determine the efficacy and safety of cetuximab (CET) combined with the FOLFOX4 regimen (infusional fluorouracil, folinic acid, and oxaliplatin) as first-line therapy for patients with aGC, who received evidence-based care (EBC).

METHODS

A total of 117 aGC patients who received EBC from March 2019 to March 2022 were enrolled. Of these, 60 in the research group (RG) received CET + FOLFOX4 as first-line therapy, whereas 57 in the control group (CG) received FOLFOX4. The efficacy [clinical response rate (RR) and disease control rate (DCR)], safety (liver and kidney dysfunction, leukopenia, thrombocytopenia, rash, and diarrhea), serum tumor marker expression [STMs; carbohydrate antigen (CA) 19-9, CA72-4, and carcinoembryonic antigen (CEA)], inflammatory indicators [interleukin (IL)-2 and IL-10], and quality of life (QOL) of the two groups were compared.

RESULTS

A markedly higher RR and DCR were observed in the RG compared with the CG, with an equivalent safety profile between the two groups. RG exhibited notably reduced CA19-9, CA72-4, CEA, and IL-2 levels following treatment, which were lower than the pre-treatment levels and those in the CG. Post-treatment IL-10 was statistically increased in RG, higher than the pre-treatment level and the CG. Moreover, a significantly improved QOL was evident in the RG.

CONCLUSION

The CET + FOLFOX4 regimen is highly effective as first-line treatment for aGC patients receiving EBC. It facilitates the suppression of STMs, ameliorates the serum inflammatory microenvironment, and enhances QOL, without increased adverse drug effects.

Perioperative Cetuximab with Cisplatin and 5-Fluorouracil in Esogastric Adenocarcinoma: A Phase II Study

PURPOSE

While perioperative chemotherapy provides a survival benefit over surgery alone in gastric and gastroesophageal junction (G/GEJ) adenocarcinomas, the results need to be improved. This study aimed to evaluate the efficacy and safety of perioperative cetuximab combined with 5-fluorouracil and cisplatin.

PATIENTS AND METHODS

Patients received six cycles of cetuximab, cisplatin, and simplified LV5FU2 before and after surgery. The primary objective was a combined evaluation of the tumor objective response (TOR), assessed by computed tomography, and the absence of major toxicities resulting in discontinuation of neoadjuvant chemotherapy (NCT) (45% and 90%, respectively).

RESULTS

From 2011 to 2013, 65 patients were enrolled. From 64 patients evaluable for the primary endpoint, 19 (29.7%) had a morphological TOR and 61 (95.3%) did not stop NCT prematurely due to major toxicity. Sixty patients (92.3%) underwent resection. Sixteen patients (/56 available, 28.5%) had histological responses (Mandard tumor regression grade ≤3). After a median follow-up of 44.5 months, median disease-free and overall survival were 24.4 [95% CI: 16.4-39.4] and 40.3 months [95% CI: 27.5-NA], respectively.

CONCLUSION

Adding cetuximab to the NCT regimen in operable G/GEJ adenocarcinomas is safe, but did not show enough efficacy in the present study to meet the primary endpoint (NCT01360086).

KRAS mutation as a predictor of insufficient trastuzumab efficacy and poor prognosis in HER2-positive advanced gastric cancer

PURPOSE

Although RAS and PIK3CA mutations have been associated with resistance to anti-EGFR antibody in colorectal cancer or trastuzumab in breast cancer, their implications for trastuzumab resistance in HER2-positive advanced gastric cancer (AGC) remains unclear. We aimed to assess the relationship between trastuzumab efficacy and mutation status in the HER family signaling pathway.

METHODS

This study retrospectively evaluated patients with HER2-positive AGC who received first-line trastuzumab-containing chemotherapy between March 2011 and November 2015. Multiplex genotyping, including KRAS, NRAS, PIK3CA, and BRAF, was then performed using the Luminex Assay, after which KRAS amplification was measured using quantitative real-time reverse transcription-polymerase chain reaction. Thereafter, the association between genetic alterations and clinical outcomes were evaluated.

RESULTS

KRAS mutation (MT) was detected in 6 of 77 patients (7.8%), whereas KRAS amplification was found in 15 of 67 patients (22%). No mutations in NRAS, PIK3CA, or BRAF were identified. The KRAS MT group showed significantly worse response rates (16.7% vs. 66.2%, P = 0.016), progression-free survival [median, 4.8 vs. 11.6 months; hazard ratio (HR), 3.95; 95% CI, 1.60-9.76; P = 0.0029], and overall survival (11.5 vs. 23.6 months; HR, 3.80; 95% CI, 1.56-9.28; P = 0.033) compared to the KRAS wild-type group. KRAS amplification had no effect on clinical outcomes.

CONCLUSION

KRAS mutation was an independent prognostic factor for poor survival and might predict insufficient trastuzumab efficacy, whereas KRAS amplification showed no prognostic significance during trastuzumab treatment. Further investigations are warranted to confirm the predictive value of KRAS status in HER2-positive AGC.

Pretreatment serum albumin-to-alkaline phosphatase ratio is an independent prognosticator of survival in patients with metastatic gastric cancer

BACKGROUND

Previous studies have suggested that a low albumin-to-alkaline phosphatase ratio (AAPR) is associated with a lower survival rate in patients with various malignancies. However, the relationship between pretreatment AAPR and the prognosis of patients with gastric cancer (GC) remains unclear.

AIM

To investigate the prognostic value of AAPR in distant metastatic GC.

METHODS

A total of 191 patients with distant metastatic cancer from a single institute were enrolled in this study. Pretreatment clinical data, including serum albumin and alkaline phosphatase levels, were collected. A chi-square test or Fisher’s exact test was applied to evaluate the correlations between AAPR and various clinical parameters in GC patients. The Kaplan–Meier method and Cox proportional hazards regression model were used to evaluate the prognostic efficacy of AAPR in metastatic GC patients. A two-sided P value lower than 0.05 was considered statistically significant.

RESULTS

A receiver operating characteristic curve indicated that 0.48 was the optimal threshold value for AAPR. AAPR ≤ 0.48 was significantly associated with bone (P < 0.05) and liver metastasis (P < 0.05). Patients with high levels of AAPR had better survival in terms of overall survival (OS) and progression-free survival (PFS), regardless of the presence of liver/bone metastasis. Pretreatment AAPR was found to be a favorable predictor of OS and PFS based on a multivariate cox regression model. AAPR-M system, constructed based on AAPR and number of metastatic sites, showed superior predictive ability relative to the number of metastatic sites for predicting survival.

CONCLUSION

Pretreatment AAPR may serve as an independent prognostic factor for predicting PFS and OS in patients with metastatic GC. Furthermore, AAPR may assist clinicians with individualizing treatment.

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.

Phase II study of cetuximab plus S-1/cisplatin therapy in Japanese patients with advanced gastric cancer

OBJECTIVE

We evaluated the efficacy and safety of first-line S-1 plus cisplatin in combination with cetuximab for Japanese patients with advanced gastric cancer, including gastroesophageal junction adenocarcinoma.

METHODS

This open-label, single arm, multicenter, phase 2 trial was conducted to assess first-line cetuximab plus S-1 plus cisplatin for advanced gastric cancer. A total of 40 patients from 10 centers were enrolled. Cetuximab was administered weekly, with the initial infusion at 400 mg/m2 and then 250 mg/m2 each subsequent week. S-1 plus cisplatin chemotherapy was concomitantly conducted in a 5-week cycle: S-1 (40-60 mg, adjusted for body surface area) was given twice daily for 3 consecutive weeks, followed by a 2-week rest period, and cisplatin (60 mg/m2) was given on day 8 of each cycle for a maximum of 8 cycles. Treatment continued until the occurrence of radiographically confirmed progressive disease, unacceptable toxicity or withdrawal of consent. The primary endpoint was the best overall response. Secondary endpoints included progression-free survival and safety.

RESULTS

A total of 40 patients were evaluable. One patient (2.5%) had a complete response; 15 patients (37.5%) had a partial response. The observed overall response rate according to the independent review committee was 40.0% (95% confidence interval, 24.9-56.7; P = 0.7043 [one-sided null hypothesis: overall response rate ≤ 43%]); median PFS was 5.6 months (95% confidence intervals, 4.2-8.3). No adverse events leading to death were reported during the study, and no specific safety concerns were observed.

CONCLUSIONS

Overall, the addition of cetuximab to S-1 plus cisplatin was well tolerated in patients with advanced gastric cancer but provided no additional clinical benefit in this study. ClinicalTrials.gov identifier: NCT01388790.

Off-Label Use of Antineoplastic Drugs to Treat Malignancies: Evidence From China Based on a Nationwide Medical Insurance Data Analysis

Purpose: Cancer is a leading cause of morbidity and mortality worldwide. Off-label (OL) use of antineoplastic drugs to treat malignancies is prevalent. In this study, we quantified and characterized OL use of antineoplastic drugs to treat malignancies in China. Methods: This was a retrospective study using nationwide data collected from 2008 to 2010. Use of antineoplastic drugs was considered OL if they were used for indications not reflected in the package insert published by the National Medical Products Administration at the time of prescription. Descriptive analysis and Spearman rank correlation were used to evaluate the frequency and pattern of OL drug use. Results: In total, 51,382 patients with malignancies, 24 categories of antineoplastic drugs, and 77 types of malignancies treated with OL drugs were included in this study. Twenty commonly used antineoplastic drugs (ICD encoded as L01) were used OL in 10-61% of cases, and four commonly used endocrine therapy antineoplastic drugs (ICD encoded as L02) were used OL in 10-19% of cases. There was a significant negative correlation between the disease constituent ratio and the average OL use rate of antineoplastic drugs for various malignancies. In contrast, there was a significant positive correlation between the average OL use rate of antineoplastic drugs and the number of malignancies treated with OL drugs. Conclusion: This study provided information regarding OL use of antineoplastic drugs for treatment of malignancies, and showed that OL use was prevalent. In addition, uncommon malignancies were more likely to be treated with OL antineoplastic drugs. Furthermore, more commonly used antineoplastic drugs were more likely to be used OL.

Treatment Strategies of Gastric Cancer-Molecular Targets for Anti-angiogenic Therapy: a State-of-the-art Review

Purpose

Recent studies have suggested that molecular targets for the anti-angiogenic therapy might constitute a basis for additional therapy in gastric cancer treatment. A vast number of molecules, receptors, pathways, specific interactions, and thus strategies that target gastric cancer angiogenesis specifically have been reported in numerous research articles and clinical trials.

Methods

We conducted a systematic literature review of molecularly targeted treatment strategies in gastric cancer on the following databases—PubMed, Google Scholar, and Scopus—on September 20, 2020. Multiple articles and evaluations were searched for studies reporting newly found and promising molecular anti-angiogenic therapy pathways. Eventually, 39 articles regarding the anti-angiogenic therapy in gastric cancer were included in the final analysis.

Results

As a consequence of the release of the pro-angiogenic molecules from the tumour cells, gastric cancer presents high angiogenic capability. Therefore, potential schemes for future treatment strategies include the decrease of the process ligands as well as the expression of their receptors. Moreover, the increase in the angiogenic inhibitor levels and direct aim for the inner walls of the endothelial cells appear as a promising therapeutic strategy. Beyond that, angiogenesis process inhibition seems to indirectly exaggerate the effects of chemotherapy in the considered patients.

Conclusions

The anti-angiogenic treatment in gastric cancer patients evaluates its significance especially in the early stages of the malignancy. The studies conducted so far show that most of the meaningful angiogenic factors and receptors with the potential molecular pathways should be further evaluated since they could potentially play a substantial role in future therapies.

GUCY2C as a biomarker to target precision therapies for patients with colorectal cancer

Introduction

Colorectal cancer (CRC) is one of the most-deadly malignancies worldwide. Current therapeutic regimens for CRC patients are relatively generic, based primarily on disease type and stage, with little variation. As the field of molecular oncology advances, so too must therapeutic management of CRC. Understanding molecular heterogeneity has led to a new-found promotion for precision therapy in CRC; underlining the diversity of molecularly targeted therapies based on individual tumor characteristics.

Areas covered

We review current approaches for the treatment of CRC and discuss the potential of precision therapy in advanced CRC. We highlight the utility of the intestinal protein guanylyl cyclase C (GUCY2C), as a multi-purpose biomarker and unique therapeutic target in CRC. Here, we summarize current GUCY2C-targeted approaches for treatment of CRC.

Expert opinion

The GUCY2C biomarker has multi-faceted utility in medicine. Developmental investment of GUCY2C as a diagnostic and therapeutic biomarker offers a variety of options taking the molecular characteristics of cancer into account. From GUCY2C-targeted therapies, namely cancer vaccines, CAR-T cells, and monoclonal antibodies, to GUCY2C agonists for chemoprevention in those who are at high risk for developing colorectal cancer, the utility of this protein provides many avenues for exploration with significance in the field of precision medicine.

Objective Quantitation of EGFR Protein Levels using Quantitative Dot Blot Method for the Prognosis of Gastric Cancer Patients

Purpose

An underlying factor for the failure of several clinical trials of anti-epidermal growth factor receptor (EGFR) therapies is the lack of an effective method to identify patients who overexpress EGFR protein. The quantitative dot blot method (QDB) was used to measure EGFR protein levels objectively, absolutely, and quantitatively. Its feasibility was evaluated for the prognosis of overall survival (OS) of patients with gastric cancer.

Materials and Methods

Slices of 2×5 μm from formalin-fixed paraffin-embedded gastric cancer specimens were used to extract total tissue lysates for QDB measurement. Absolutely quantitated EGFR protein levels were used for the Kaplan-Meier OS analysis.

Results

EGFR protein levels ranged from 0 to 772.6 pmol/g (n=246) for all gastric cancer patients. A poor correlation was observed between quantitated EGFR levels and immunohistochemistry scores with ρ=0.024 and P=0.717 in Spearman's correlation analysis. EGFR was identified as an independent negative prognostic biomarker for gastric cancer patients only through absolute quantitation, with a hazard ratio of 1.92 (95% confidence interval, 1.05–3.53; P=0.034) in multivariate Cox regression OS analysis. A cutoff of 208 pmol/g was proposed to stratify patients with a 3-year survival probability of 44% for patients with EGFR levels above the cutoff versus 68% for those below the cutoff based on Kaplan-Meier OS analysis (log rank test, P=0.002).

Conclusions

A QDB-based assay was developed for gastric cancer specimens to measure EGFR protein levels absolutely, quantitatively, and objectively. This assay should facilitate clinical trials aimed at evaluation of anti-EGFR therapies retrospectively and prospectively for gastric cancer.

Targeting EGFR in Esophagogastric Cancer

Esophagogastric cancer (EGC) remains a major cause of cancer-related mortality. Overall survival in the metastatic setting remains poor, with few molecular targeted approaches having been successfully incorporated into routine care to-date: only first line anti-HER2 therapy in ERBB2-expressing tumors, second line anti-VEGFR2 therapy with ramucirumab in unselected patients, and pembrolizumab in PD-L1 expressing or MSI-H patients. EGFR inhibitors were extensively studied in EGC, including phase III trials with cetuximab (EXPAND), panitumumab (REAL3), and gefitinib (COG). All three trials were conducted in unselected populations, and therefore, failed to demonstrate clinical benefit. Here, we review previous attempts at targeting EGFR in EGC and potential future biomarkers for targeting this pathway in patients with EGFR-amplified tumors.

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.

Gastric Cancer: Epidemiology, Risk Factors, Classification, Genomic Characteristics and Treatment Strategies

Gastric cancer (GC) is one of the most common malignancies worldwide and it is the fourth leading cause of cancer-related death. GC is a multifactorial disease, where both environmental and genetic factors can have an impact on its occurrence and development. The incidence rate of GC rises progressively with age; the median age at diagnosis is 70 years. However, approximately 10% of gastric carcinomas are detected at the age of 45 or younger. Early-onset gastric cancer is a good model to study genetic alterations related to the carcinogenesis process, as young patients are less exposed to environmental carcinogens. Carcinogenesis is a multistage disease process specified by the progressive development of mutations and epigenetic alterations in the expression of various genes, which are responsible for the occurrence of the disease.

The promising role of monoclonal antibodies for gastric cancer treatment

Gastric cancer (GC) is the second leading cause of cancer-related death world-wide. Despite improvements in prevention, early detection and various therapeutic options, the prognosis is still poor. GC is often diagnosed at an advanced stage with survivals less than 1 year. Chemotherapy as the mainstay of treatment in advanced stage is not of notable advantages, underlining the need for novel more effective therapeutic options. Based on current knowledge of molecular and cellular mechanisms, a number of novel biologic approaches such as monoclonal antibodies have been recently introduced for cancer treatment that mainly affect the immune system or target signaling pathways playing role in cancer and metastasis development. In this review, various monoclonal antibodies for GC therapy were explained.

Epidermal Growth Factor Receptor Family and its Role in Gastric Cancer

Despite the gradual decrease in incidence, gastric cancer is still the third leading cause of cancer death worldwide. Although chemotherapy enhances overall survival and quality of life in advanced disease, the median overall survival is < 12 months. In recent years, the human epidermal growth factor receptor (ErbB) family has been extensively investigated in gastric cancer. The ErbB family is composed of four closely-related members: ErbB-1 (HER1 or epidermal growth factor receptor, EGFR), ErbB-2 (HER2), ErbB-3 (HER3), and ErbB-4 (HER4), all of which play a critical role in regulating cell growth, proliferation and migration of tumors. It is well known that gastric cancer overexpresses HER in a heterogeneous pattern, especially EGFR, and HER2. HER3 is another important member of the ErbB family that preferentially activates the phosphatidylinositol 3-kinase (PI3K) pathway. Furthermore, its heterodimerization with HER2 seems fundamental for steering HER2-overexpressing breast cancer tumor growth. Less is known about the impact of HER4 on gastric cancer. Improved survival from the use of trastuzumab has paved the way for ErbB receptor family-targeted treatments in gastric cancer. However, unlike trastuzumab, ErbB receptor-targeted drugs have not consistently maintained the encouraging results obtained in preclinical and early clinical trials. This may be attributable to the intrinsic heterogeneity of gastric cancer and/or to the lack of standardized test quality for established biomarkers used to evaluate these biological targets. This review presents an overview of the most recent clinical studies on agents targeting the ErbB family in gastric cancer.

Optimal management of gastroesophageal junction cancer

Although recent decades have witnessed incremental improvements in the treatment of gastroesophageal junction (GEJ) carcinoma, outcomes remain modest. For locally advanced esophageal cancer, the addition of chemotherapy and/or radiation to surgery is considered the standard of care. Chemotherapy remains the primary treatment for metastatic disease and improves survival over best supportive care. However, the prognosis for patients with GEJ cancers, which are treated along the same paradigms as esophageal and gastric carcinomas, remain poor because of the emergence of chemoresistance and limited targeted therapeutic approaches, which include agents that target the HER2 and vascular endothelial growth factor pathways. Evaluation of immune checkpoint inhibitors in the chemorefractory setting have confirmed the activity of immunotherapy in esophagogastric cancer. Ongoing immunotherapeutic strategies are being evaluated in both the locally advanced and metastatic settings. This review focuses on the treatment of locally advanced and metastatic GEJ carcinomas, which encompass all tumors that have an epicenter within 5 cm proximal or distal to the anatomical Z-line (Siewert classification). Because the vast majority of GEJ tumors are adenocarcinoma, the management of adenocarcinoma is the focus of this review. Evolving approaches and areas of clinical equipoise are discussed.

Co-operative groups in the development of chemotherapy for gastric cancer

In the multimodality treatment strategy for gastric cancer, chemotherapy has an important role in conferring survival benefit. For the last three decades, great progress has been achieved in adjuvant and palliative chemotherapy. Powerful combination regimens using doublet or triplet cytotoxic agents have been developed and new molecular targeted drugs, including trastuzumab and ramucirumab, have been introduced in clinical practice. These advances have resulted from the accumulation of many clinical trials. A well-designed phase III trial can change standard treatment; however, such a trial is hard to complete due to its huge cost and need to recruit many patients. Some co-operative groups have actively made efforts at fundraising and patient recruitment, which can make implementation of high-quality and large-scale phase III trials possible. This review summarizes the development of chemotherapy for gastric cancer with focus on co-operative groups around the world, considering effective treatment developments in gastric cancer. We studied 11 active co-operative groups, including six in Europe, two in the United States, and three in Japan, that have completed one or more phase III trials cited in the major guidelines. Each co-operative group had its own characteristics and contributed to the establishment of standard treatment in each region. International collaboration in the development of gastric cancer treatment may be difficult due to regional differences in standards of care, particularly for resectable gastric cancer. Whereas, intergroup collaboration within each region is a reasonable method to effectively develop treatments for resectable and advanced gastric cancer.

What's New in Gastric Cancer: The Therapeutic Implications of Molecular Classifications and Future Perspectives

Despite some remarkable innovations and the advent of novel molecular classifications the prognosis of patients with advanced gastric cancer (GC) remains overall poor and current clinical application of new advances is disappointing. During the last years only Trastuzumab and Ramucirumab have been approved and currently used as standard of care targeted therapies, but the systemic management of advanced disease did not radically change in contrast with the high number of molecular drivers identified. The Cancer Genome Atlas (TCGA) and Asian Cancer Research Group (ACRG) classifications paved the way, also for GC, to that more contemporary therapeutic approach called "precision medicine" even if tumor heterogeneity and a complex genetic landscape still represent a strong barrier. The identification of specific cancer subgroups is also making possible a better selection of patients that are most likely to respond to immunotherapy. This review aims to critically overview the available molecular classifications summarizing the main druggable molecular drivers and their possible therapeutic implications also taking advantage of new technologies and acquisitions.

Gastric cancer: Basic aspects

Despite major breakthroughs in the field of personalized medicine, gastric cancer (GC) remains a clinically challenging disease, characterized by scarce effective treatment options and the lack of reliable molecular tools for the prediction of patient outcome and response to therapy. The pronounced molecular heterogeneity that dictates the phenotypical aggressiveness of gastric neoplasms severely limits the antitumor efficacy of targeted agents brought to clinical trials, and constitutes a favorable setting for the emergence of refractory tumors exhibiting multidrug resistance. We will review the most recent advances in our understanding of GC biology, which are underlying the development and clinical testing of novel targeted therapeutic agents. We will also emphasize how their efficacy and acquired resistance relate to the aberrant molecular signatures that drive gastric malignancy.

Genomic markers of resistance to targeted treatments in gastric cancer: potential new treatment strategies

Gastric cancer is a highly heterogeneous disease, displaying a complex genomic landscape and an unfavorable outcome with standard therapies. Based on distinctive genomic alterations, novel targeted agents have been developed with the aim of personalizing treatments and improving patient outcome. However, a subgroup of patients is primarily treatment-resistant, and even in the initially sensitive population, secondary resistance emerges, thus limiting therapeutic benefit. In this review, we summarize the clinical data about standard targeted agents in gastric cancer, specifically anti-HER2 treatments and antivascular therapies. We also illustrate the available evidence regarding molecular mechanisms of resistance to these agents and we discuss potential strategies for new targeted treatments that could overcome such resistance.

Advances in molecular, genetic and immune signatures of gastric cancer: Are we ready to apply them in our patients' decision making?

In the last few years we have witnessed a vast expansion of our knowledge regarding the molecular and genetic profile of gastric cancer. The molecular subtypes described have shed light on the pathogenesis of the disease, thus prompting the development of new therapeutic strategies and favoring a more individualized approach for treatment. Most of the clinical trials for so called targeted therapies could be considered, at best, partially successful. In addition, checkpoint inhibitors have recently been added to our armamentarium in later stages of the disease, and combinations with chemotherapy and targeted agents are currently under development. In view of the rapid advances of molecular oncology, a new challenge for the clinical oncologist arises: The appropriate patient selection for each new therapy, which can be made possible only through the implementation of predictive biomarkers in our therapy decision making.

Targeted Therapies for Targeted Populations: Anti-EGFR Treatment for EGFR-Amplified Gastroesophageal Adenocarcinoma

Previous anti-EGFR trials in unselected patients with gastroesophageal adenocarcinoma (GEA) were resoundingly negative. We identified EGFR amplification in 5% (19/363) of patients at the University of Chicago, including 6% (8/140) who were prospectively screened with intention-to-treat using anti-EGFR therapy. Seven patients received ≥1 dose of treatment: three first-line FOLFOX plus ABT-806, one second-line FOLFIRI plus cetuximab, and three third/fourth-line cetuximab alone. Treatment achieved objective response in 58% (4/7) and disease control in 100% (7/7) with a median progression-free survival of 10 months. Pretreatment and posttreatment tumor next-generation sequencing (NGS), serial plasma circulating tumor DNA (ctDNA) NGS, and tumor IHC/FISH for EGFR revealed preexisting and/or acquired genomic events, including EGFR-negative clones, PTEN deletion, KRAS amplification/mutation, NRAS, MYC, and HER2 amplification, and GNAS mutations serving as mechanisms of resistance. Two evaluable patients demonstrated interval increase of CD3+ infiltrate, including one who demonstrated increased NKp46+, and PD-L1 IHC expression from baseline, suggesting an immune therapeutic mechanism of action. EGFR amplification predicted benefit from anti-EGFR therapy, albeit until various resistance mechanisms emerged.Significance: This paper highlights the role of EGFR inhibitors in EGFR-amplified GEA-despite negative results in prior unselected phase III trials. Using serial ctDNA and tissue NGS, we identified mechanisms of primary and acquired resistance in all patients, as well as potential contribution of antibody-dependent cell-mediated cytotoxicity to their clinical benefit. Cancer Discov; 8(6); 696-713. ©2018 AACR.See related commentary by Strickler, p. 679This article is highlighted in the In This Issue feature, p. 663.

Novel Targeted Therapies for Esophagogastric Cancer

Gastroesophageal cancer (GEC) remains a major cause of cancer-related mortality worldwide. Although the incidence of distal gastric adenocarcinoma (GC) is declining in the United States, proximal esophagogastric junction adenocarcinoma (EGJ) is increasing in incidence. GEC, including GC and EGJ, is treated uniformly in the metastatic setting. Overall survival in the metastatic setting remains poor. Molecular characterization of GEC has identified mutations and copy number variations, along with other oncogenes, biomarkers, and immuno-oncologic checkpoints that may serve as actionable therapeutic targets. This article reviews these key aberrations, their impact on protein expression, therapeutic implications, and clinical directions within each pathway.

Novel Systemic Therapies for Advanced Gastric Cancer

Gastric cancer (GC) is the second leading cause of cancer mortality and the fourth most commonly diagnosed malignant diseases. While continued efforts have been focused on GC treatment, the introduction of trastuzumab marked the beginning of a new era of target-specific treatments. Considering the diversity of mutations in GC, satisfactory results obtained from various target-specific therapies were expected, yet most of them were unsuccessful in controlled clinical trials. There are several possible reasons underlying the failures, including the absence of patient selection depending on validated predictive biomarkers, the inappropriate combination of drugs, and tumor heterogeneity. In contrast to targeted agents, immuno-oncologic agents are designed to regulate and boost immunity, are not target-specific, and may overcome tumor heterogeneity. With the successful establishment of predictive biomarkers, including Epstein-Barr virus pattern, microsatellite instability status, and programmed death-ligand 1 (PD-L1) expression, as well as ideal combination regimens, a new frontier in the immuno-oncology of GC treatment is on the horizon. Since the field of immuno-oncology has witnessed innovative, practice-changing successes in other cancer types, several trials on GC are ongoing. Among immuno-oncologic therapies, immune checkpoint inhibitors are the mainstay of clinical trials performed on GC. In this article, we review target-specific agents currently used in clinics or are undergoing clinical trials, and highlight the future clinical application of immuno-oncologic agents in inoperable GC.

Evaluation of short-term effectiveness of eight targeted agents combined with chemotherapy for treating esophageal-gastric junction adenocarcinoma: A network meta-analysis

This study aimed to evaluate the short-term effectiveness of eight targeted agents (ramucirumab, bevacizumab, rilotumumab, panitumumab, cetuximab, trebananib, trastuzumab, matuzumab) plus chemotherapy in esophageal-gastric junction adenocarcinoma (EGJA) by a network meta-analysis (NMA). PubMed, Embase, and Cochrane Library databases were systematically retrieved for randomized clinical trials (RCTs) concerning targeted agents plus chemotherapy in the treatment of EGJA. This NMA combined both direct and indirect evidence to evaluate odds ratio (OR) and to draw the surface under the cumulative ranking curve (SUCRA). In total 11 RCTs with 3649 EGJA patients (1907 patients treated with targeted agents plus chemotherapy were regarded as the case group, and 1742 patients with placebo plus chemotherapy were assigned into the control group) were enrolled in this study. Targeted agents in terms of stable disease (SD), partial response (PR), disease control rate (DCR), and overall response ratio (ORR) with the SUCRA values of 0.838, 0.807, 0.934, and 0.793, respectively. Cetuximab and trastuzumab, with the SUCRA values of 0.884 and 0.758, came on top as the best outcomes for treating EGJA in terms of progressive disease (PD) and complete response (CR). Cluster analysis results indicated that ramucirumab plus chemotherapy might be the optimal treatment for EGJA. Our findings indicated that ramucirumab plus chemotherapy might be the optimal treatment for EGJA amongst the nine treatment regimens, which provided clinical guidance for clinicians in the treatment of EGJA.

Management of Patients With Adenocarcinoma or Squamous Cancer of the Esophagus

Esophageal cancer is characterized by early and frequent metastasis. Surgery is the primary treatment for early-stage disease, whereas patients with patients with locally advanced disease receive perioperative chemotherapy or chemoradiotherapy. Squamous cancers can be treated with primary chemoradiotherapy without surgery, depending on their response to therapy and patient tolerance for subsequent surgery. Chemotherapy with a fluorinated pyrimidine and a platinum agent, followed by later treatment with taxanes and irinotecan, provides some benefit. Agents that inhibit the erb-b2 receptor tyrosine kinase 2 (ERBB2 or HER2), or vascular endothelial growth factor, including trastuzumab, ramucirumab, and apatinib, increase response and survival times. Esophageal adenocarcinomas have mutations in tumor protein p53 and mutations that activate receptor-associated tyrosine kinase, vascular endothelial growth factor, and cell cycle pathways, whereas esophageal squamous tumors have a distinct set of mutations. Esophageal cancers develop systems to evade anti-tumor immune responses, but studies are needed to determine how immune checkpoint modification contributes to esophageal tumor development.

First-line dose-dense chemotherapy with docetaxel, cisplatin, folinic acid and 5-fluorouracil (DCF) plus panitumumab in patients with locally advanced or metastatic cancer of the stomach or gastroesophageal junction: final results and biomarker analysis from an Italian oncology group for clinical research (GOIRC) phase II study

BACKGROUND

Survival for patients with advanced gastroesophageal cancer (AGC) using standard treatment regimens is poor. EGFR overexpression is common in AGC and associated with poor prognosis. We hypothesized that increasing the dose intensity of chemotherapy and adding panitumumab could improve efficacy.

METHODS

HER2 negative, PS 0-1 patients, received up to 4 cycles of panitumumab 6 mg/kg d 1, docetaxel 60 mg/m2 d 1, cisplatin 50 mg/m2 d 1, l-folinic acid 100 mg/m2 d 1-2, followed by 5-FU 400 mg/m2 bolus d 1-2, and then 600 mg/m2 as a 22 h c.i. on d 1-2, q15 d, plus pegfilgrastim 6 mg on d 3. Patients with disease control after 4 cycles received panitumumab until progression.

RESULTS

From 05/2010 to 01/2014, 52 patients (75% male; median age 64.5 y; metastatic 90%, locally advanced 10%; 96% adenocarcinoma; 25% GEJ) were recruited. Three CR, 29 PR, 10 SD and 8 PD were observed, for an ORR by ITT (primary endpoint) of 62% (95% CI, 48%-75%) and a DCR of 81%. Median TTP was 4.9 months (95% CI, 4.2-7.0) and mOS 10 months (95% CI, 8.2- 13.5). Most frequent G3-4 toxicities: leucopenia (29%), asthenia (27%), skin rash (25%), neutropenia (19%), anorexia (17%), febrile neutropenia (13%), and diarrhea (15%). EGFR expression tested both with dd-PCR and FISH was not associated with any significant clinical benefit from treatment.

CONCLUSIONS

Dose-dense DCF plus panitumumab is an active regimen. However, the toxicity profile of this limits further development. Further research on predictive biomarkers for treatment efficacy in AGC is required.Clinical trial information: 2009-016962-10.

The role of anti-EGFR agents in the first-line treatment of advanced esophago-gastric adenocarcinoma: a meta-analysis

The role of anti-epidermal growth factor receptor (EGFR) therapy is controversial in patients with esophago-gastric adenocarcinoma. We performed this meta-analysis to evaluate whether the addition of an anti-EGFR agent to chemotherapy can produce survival benefits in patients with advanced esophageal adenocarcinoma, gastric adenocarcinoma, or gastroesophageal junction adenocarcinoma. Electronic databases were searched for eligible randomized studies. From six studies, 1,817 patients were included in the meta-analysis of hazard ratios (HRs) for progression-free survival (PFS) and overall survival (OS). Compared with chemotherapy alone, anti-EGFR agents in combination with chemotherapy were significantly associated with shorter PFS (HR = 1.14 [95% confidence interval {CI}, 1.01-1.28], P = 0.03). In terms of OS, the addition of an anti-EGFR agent to chemotherapy showed no advantage (HR = 1.10 [95% CI, 0.98-1.23], P = 0.11). In addition, the combination of an anti-EGFR agent with chemotherapy significantly increased some grade 3/4 toxicities including diarrhea (risk ratio {RR} = 1.42, [95% CI, 1.03-1.94], P = 0.03), mucositis (RR = 3.30 [95% CI, 1.54-7.07], P = 0.002), and skin rash (RR = 6.82 [95% CI, 3.15-14.78], P < 0.00001). In conclusion, this meta-analysis indicates that the addition of an anti-EGFR agent to chemotherapy conveys no additional benefit for patients with advanced esophago-gastric adenocarcinoma. As of now, anti-EGFR agents should not be used in the first-line treatment of adenocarcinoma of the upper gastrointestinal tract.

Progress in the treatment of advanced gastric cancer

Gastric cancer is one of the most common malignant tumors in the digestive system. Surgery is currently considered to be the only radical treatment. As surgical techniques improve and progress is made in traditional radiotherapy, chemotherapy, and the implementation of neoadjuvant therapy, the 5-year survival rate of early gastric cancer can reach >95%. However, the low rate of early diagnosis means that most patients have advanced-stage disease at diagnosis and so the best surgical window is missed. Therefore, the main treatment for advanced gastric cancer is the combination of neoadjuvant chemoradiotherapy, molecular-targeted therapy, and immunotherapy. In this article, we summarize several common methods used to treat advanced gastric cancer and discuss the progress made in the treatment of gastric cancer in detail. Only clinical practice and clinical research will allow us to prolong the survival time of patients and allow the patients to truly benefit by paying attention to the individual patient characteristics, drug choice, and developing a reasonable and comprehensive treatment plan.

Insights into next developments in advanced gastric cancer

PURPOSE OF REVIEW

The purpose of the review is to delineate novel approaches for biology-based treatment in advanced gastric cancer. We reviewed the latest translational and clinical research articles and congress presentations.

RECENT FINDINGS

A new molecular classification of gastric cancer based on histology, genetic and proteomic alterations has evolved. It provides a roadmap for development of new drugs and combinations and for patient stratification. Anti-HER2 treatment, which is an effective strategy in metastatic gastric cancer, is now also being studied in the perioperative setting. However, resistance mechanisms in advanced disease are poorly understood and optimal patient selection remains challenging. Targeting angiogenesis is an emerging concept in the management of advanced gastric cancer, and ramucirumab has prolonged survival in the second line either as a monotherapy or in combination with paclitaxel. Biomarkers for selecting patients who benefit from ramucirumab are still lacking. Immune checkpoint blockade and inhibition of cancer stemness targets are other emerging directions for the medical treatment of gastric cancer. Large-scale international studies are ongoing.

SUMMARY

Promising biology-based treatment strategies are evolving. But tumor heterogeneity which is an inherent feature of gastric cancer challenges the development of molecularly targeted and personalized treatment strategies.

Suggestion of added value by bevacizumab to chemotherapy in patients with unresectable or recurrent small bowel cancer

PURPOSE

Standard therapy for advanced small bowel adenocarcinoma (SBA) has not yet been established. The present study assessed the efficacy and safety of chemotherapy (CT) in association with molecular targeting approaches for SBA.

METHODS

The histories of 33 advanced SBA patients from six different institutions in Japan, who received CT from 2008 to 2016, were retrospectively examined for background, clinical course and outcome.

RESULTS

Median patient age was 65 years (range 39-83). Primary tumor was located in the duodenum in 21 patients (67%), the ampulla of Vater in three patients (9%), the jejunum in seven patients (21%) and the ileum in one patient (3%). Histologically, well-to-moderately and poorly differentiated adenocarcinoma were identified in 20 (61%) and nine (27%) patients, respectively. Thirteen patients received a single CT regimen, seven patients received two types of CT regimen, and 13 patients received three or more CT regimens. As first-line CT, modified FOLFOX6, capecitabine plus oxaliplatin, and S-1 plus cisplatin were employed in 13, 1, and 4 patients, respectively. The response rate (RR) and median progression-free survival (PFS) were 25% and 6.0 months, respectively. Median overall survival (OS) was 13.0 months. Nine out of the 33 patients received bevacizumab-containing CT and three received cetuximab-containing CT. Median OS of bevacizumab-containing CT patients was 21.9 months. No unexpected serious adverse events were observed.

CONCLUSIONS

The analysis indicates that combination CT for advanced SBA is associated with modest efficacy and safety, and bevacizumab-containing CT may contribute to favorable outcome in these patients.

Update on Gastroesophageal Adenocarcinoma Targeted Therapies

Gastroesophageal cancer (GEC) remains a major cause of cancer-related mortality worldwide. Although the incidence of distal gastric adenocarcinoma (GC) is declining in the United States, proximal esophagogastric junction adenocarcinoma (EGJ) incidence is rising. GC and EGJ, together, are treated uniformly in the metastatic setting as GEC. Overall survival in the metastatic setting remains poor, with few molecular targeted approaches having been successfully incorporated into routine care to date-only first-line anti-HER2 therapy for ERBB2 amplification and second-line anti-VEGFR2 therapy. This article reviews aberrations in epidermal growth factor receptor, MET, and ERBB2, their therapeutic implications, and future directions in targeting these pathways.

Advanced gastric adenocarcinoma: optimizing therapy options

INTRODUCTION

Gastric adenocarcinoma (GAC) is the fifth most common cancer and third leading cause of cancer related mortality worldwide. When localized, cure is achievable with surgery and adjunctive therapies in some patients, however, once advanced, GAC is not a curable condition. Only two targeted agents (trastuzumab and ramucirumab) have been approved and apatinib was approved only in China. Because of the heterogeneous nature of GAC, it is not possible to assess a standard therapeutic approach. Areas covered: In this review, we aimed to describe the optimal systemic therapy regimens for advanced GAC. A literature search was performed to identify all phase II-III studies about advanced GAC from PubMed, clinicaltrials.gov, American Society of Clinical Oncology (ASCO) and European Society for Medical Oncology (ESMO) websites. Expert commentary: A combination of a platinum compound and a fluoropyrimidine is ideal as first line therapy. Trastuzumab should be added if the tumor is HER2 positive. In the second line setting, paclitaxel/ramucirumab is preferred over ramucirumab alone. Recently, two similar molecular classifications for GAC have been proposed. A better understanding of molecular and immune biology of GAC could identify new therapeutic targets.

Targeted therapies for gastric cancer: failures and hopes from clinical trials

Gastric cancer is the third leading cause of cancer mortality worldwide. As surgery is the only curative treatment strategy and conventional chemotherapy has shown limited efficacy -with a median overall survival of 10 months- new treatments are urgently needed. Trastuzumab and Ramucirumab (targeting HER2 and VEGFR2, respectively) are the only targeted therapies approved so far. Indeed, most Phase III clinical trials evaluating molecular drugs in gastric cancer failed. This review will retrace the relevant clinical trials with molecular therapies performed in gastric cancer patients, discussing the possible reasons for their failure and indicating new perspective for a real improvement of the treatment of this disease.

Combination Approach: the Future of the War Against Cancer

Cancer remains one of the major health problems worldwide and is responsible for one in eight deaths. The worldwide research against cancer as well as genome wide association studies was successful in indentifying the loci associated with cancer but still a substantial amount of casualty remains unexplained. The reason being the cancer cell rapidly develops resistance against the chemotherapeutic or chemopreventive agent in use. Over the last decade, the thorough understanding of molecular and biochemical mechanisms of the carcinogenesis process lead to the rationale of combining anti-cancer agents (therapeutic as well as chemopreventive) to target multiple pathways. Scientists, the world over trying various combinations of chemotherapy, radiation therapy, chemopreventive agents, nanoparticles, etc., in order to specifically as well as efficiently target cancer cells. The present review article summarizes the recent advances in the combination approach against cancer in order to enhance efficacy of treatment with minimal side effects.

RANKL/RANK pathway abrogates cetuximab sensitivity in gastric cancer cells via activation of EGFR and c-Src

Overexpression of EGFR is commonly seen in gastric cancer (GC). However, patients with GC show resistance to anti-EGFR treatments. RAS mutations are rare in GC and cannot explain de novo resistance to EGFR treatments. Therefore, it is particularly important to explore the mechanisms of resistance to anti-EGFR treatments. The RANKL activates the EGFR pathway in osteoclasts, and the RANK is expressed in gastric carcinoma. Whether the RANKL/RANK pathway has an effect on the EGFR pathway in GC remains unknown. Expressions of EGFR and RANK in GC tissues were detected using immunohistochemical staining. Nineteen patients (28%) showed high-level RANKL expression, and 33 patients (48%) showed high-level RANK expression. There was a positive correlation between expression of EGFR and RANK (P<0.001). In an in vitro study, RANKL induced activation of the EGFR pathway and further abrogated cetuximab sensitivity in GC cells. Knockdown of RANK or use of the RANKL inhibitor enhanced cetuximab effect by decreasing RANKL-induced EGFR activation. Furthermore, we showed that c-SRC mediated the EGFR activation induced by the RANKL/RANK pathway and that c-SRC inhibitor reversed the suppression of RANKL on the effect of cetuximab. In conclusion, our results suggest that in GC cells, the RANKL/RANK pathway activates the EGFR pathway and thereby causes resistance to anti-EGFR treatments.

Targeted therapies for advanced and metastatic adenocarcinoma of the gastroesophageal junction: is there something new?

Despite improvements in systemic chemotherapy (CT), the prognosis of metastatic adenocarcinoma of the gastroesophageal junction remains poor. Over the years, new targeting agents have become available and were tested, with or without CT, in first or subsequent lines of therapy. The epidermal growth factor receptor family was targeted with monoclonal antibodies (MoAbs) (trastuzumab, cetuximab, panitumumab) and tyrosin kinase inhibitors (TKIs) (lapatinib, erlotinib, gefitinib). Only trastuzumab, in combination with cisplatin and fluoropyrimidines, significantly improved overall survival (OS) in first-line therapy (13.8 vs. 11.1 months). Angiogenesis also was targeted with MoAbs (bevacizumab and ramucirumab); ramucirumab, a vascular endothelial growth factor-receptor 2 antagonist, enhanced OS in two phase III studies in the first (9.6 vs. 7.4 months) and subsequent lines of treatment (5.2 vs. 3.8 months), while the bevacizumab study was negative. TKIs (sunitinib, sorafenib, regorafenib, apatinib) were tested in this setting in phase II studies in the second/third line, only showing modest antitumor activity. The hepatocyte growth factor receptor (MET) was targeted in untreated patients in a phase III trial with MoAb rilotumumab, with or without CT, but the study was stopped because of mortality excess in the rilotumumab arm. Mammalian target of rapamycin (MTOR) pathway inhibition with everolimus was tested in pretreated patients in a placebo-controlled phase III trial who failed to improve OS (5.4 vs. 4.3 months). In conclusion, considering the modest survival gain obtained overall, the high cost of these therapies and the quality of life issue must be primarily considered in treating these patients.

Molecular classification of gastric cancer: Towards a pathway-driven targeted therapy

Gastric cancer (GC) is the third leading cause of cancer mortality worldwide. Although surgical resection is a potentially curative approach for localized cases of GC, most cases of GC are diagnosed in an advanced, non-curable stage and the response to traditional chemotherapy is limited. Fortunately, recent advances in our understanding of the molecular mechanisms that mediate GC hold great promise for the development of more effective treatment strategies. In this review, an overview of the morphological classification, current treatment approaches, and molecular alterations that have been characterized for GC are provided. In particular, the most recent molecular classification of GC and alterations identified in relevant signaling pathways, including ErbB, VEGF, PI3K/AKT/mTOR, and HGF/MET signaling pathways, are described, as well as inhibitors of these pathways. An overview of the completed and active clinical trials related to these signaling pathways are also summarized. Finally, insights regarding emerging stem cell pathways are described, and may provide additional novel markers for the development of therapeutic agents against GC. The development of more effective agents and the identification of biomarkers that can be used for the diagnosis, prognosis, and individualized therapy for GC patients, have the potential to improve the efficacy, safety, and cost-effectiveness for GC treatments.

Clinical and pathological characteristics of colorectal polyps: Analysis of 180 cases

AIM: To investigate the clinical and pathological characteristics of colorectal polyps.

METHODS: From January 2014 to March 2015, 90 patients with colorectal adenomatous polyps treated at the Affiliated Hospital of Youjiang Medical College for Nationalities were included in a study group, and 90 patients with non-adenomatous polyps were included in a control group. The clinical and pathological characteristics were compared between the two groups of patients.

RESULTS: The rate of bloody stool and average age differed significantly between the two groups (P < 0.05), although there was no significant difference in the change in stool character, anal pendant expansion, diarrhea, abdominal pain, body mass index (BMI) or gender (P > 0.05). The rates of high-grade intraepithelial neoplasia, low-grade intraepithelial neoplasia, lobulation, mucosal roughness and erosion, sessile polyps, multiple polyps, and polyps larger than 1 cm in diameter were significantly higher in the study group than in the control group (P < 0.05).

CONCLUSION: Older age and bloody stool are main risk factors for adenomatous polyps. The presence of high-grade intraepithelial neoplasia, low-grade intraepithelial neoplasia, lobulation, mucosal roughness and erosion, sessile polyps, multiple polyps, or polyps larger than 1 cm in diameter suggests the possibility of malignant transformation.

Predictive biomarkers for targeted and cytotoxic agents in gastric cancer for personalized medicine

Gastric cancer (GC) is the fourth most common cancer and the second leading cause of cancer. The treatment of GC remains challenging as the outcomes achieved with surgery alone or adjuvant or neoadjuvant chemotherapy and radiotherapy are relatively poor. New treatment strategies are emerging and are being tested in solid tumors including GC. Over the past few years, the treatment of metastatic colorectal cancer (CRC) has made great advances, but strategies to manage GC have improved little. Multiple drug resistance is common in GC chemotherapy and targeted therapy; some patients appear to receive treatment that is suboptimal or even inefficacious. Unfortunately, there are few validated predictive biomarkers to guide the tailored treatment of GC. ToGA and AVAGAST are two phase III trials that tested the efficacy and safety of targeted agents in advanced gastric cancer (AGC), and results clearly indicated that patients need to be selected and that targeted agents are the best hope for better results. This review aims to provide an overview of potential predictive biomarkers for cytotoxic and targeted agents in GC.

Monoclonal antibodies for treating gastric cancer: promises and pitfalls

INTRODUCTION

Gastric cancer (GC) presents dismal prognosis when diagnosed at advanced stages, standard chemotherapy having shown little efficacy. Introduction of biotherapies interfering with novel targets and signaling pathways is currently an emerging strategy.

AREAS COVERED

Only two monoclonal antibodies (trastuzumab and ramucirumab) have been approved, mostly in association with cytotoxics. Conversely, testing other promising biotherapies (panitumumab, cetuximab, bevacizumab, rilotumumab) have yielded conflicting results, since encouraging early clinical trials have failed to be confirmed in larger phase-III studies. Empirical and underpowered strategies when designing combinational studies, lack of comprehensive knowledge of pharmacokinetics/pharmacodynamics (PK/PD) relationships, and underestimation of the large inter-patient variability in drug exposure levels with monoclonal antibodies, could explain the failures in developing biotherapies in gastric cancer. This review covers the achievements and limits of monoclonal antibodies in gastric cancer and proposes clues to overcome current failures.

EXPERT OPINION

Trastuzumab efficacy could be improved thanks to its combination with triplet chemotherapy or with another anti-HER2 agents or in continuation during second-line chemotherapy. Concerning ramucirumab, further studies are necessary to prove its interest in first line treatment of advanced GC, to use the optimal dose in each patient-given the large inter-patients variability, and to find predictive biomarkers of efficacy.

Clinical impact of tumour biology in the management of gastroesophageal cancer

The characterization of oesophageal and gastric cancer into subtypes based on genotype has evolved in the past decade. Insights into the molecular landscapes of gastroesophageal cancer provide a roadmap to assist the development of new drugs and their use in combinations, for patient stratification, and for trials of targeted therapies. Trastuzumab is the only approved treatment for gastroesophageal cancers that overexpress HER2. Acquired resistance usually limits the duration of response to this treatment, although a number of new agents directed against HER2 have the potential to overcome or prolong the time until resistance occurs. Beyond that, anti-VEGFR2 therapy with ramucirumab was the first biological treatment strategy to produce a survival benefit in an unselected population of patients with chemotherapy-refractory gastroesophageal cancer. Large initiatives are starting to address the role of biomarker-driven targeted therapy in the metastatic and in the perioperative setting for patients with this disease. Immunotherapy also holds promise, and our understanding of subsets of gastroesophageal cancer based on patterns of immune response continues to evolve. Efforts are underway to identify more relevant genomic subsets through genomic screening, functional studies, and molecular characterization. Herein, we provide an overview of the key developments in the treatment of gastroesophageal cancer, and discuss potential strategies to further optimize therapy by targeting disease subtypes.

High EGFR and low p-Akt expression is associated with better outcome after nimotuzumab-containing treatment in esophageal cancer patients: preliminary clinical result and testable hypothesis

The epidermal growth factor receptor (EGFR) is widely overexpressed in esophageal squamous cell carcinoma (ESCC) and it results is associated with a poor prognosis. Identifying the subgroup of ESCC patients who are sensitive to EGFR-targeted therapy is a key point to facilitate its medical use.

We retrospectively analyzed 32 ESCC patients treated with the combination of nimotuzumab (h-R3) and radiotherapy (RT) or chemoradiotherapy (CRT). Expression of EGFR and phosphorylated proteins associated with EGFR signaling pathway, i.e. p-Akt and p-Erk, were assessed with immunohistochemistry (IHC) for all patients. Correlations between these proteins' expression levels and overall survival (OS) were assessed.

High expression of EGFR, p-Akt and p-Erk was detected in 53.1% (17/32), 54.8% (17/31) and 59.4% (19/32) of tumors respectively. No significant differences in OS were found between high EGFR, p-Akt and p-Erk expression groups and their respective counterparts. Of note, significantly better overall survival was observed in patients with coexistence of high EGFR expression and low p-Akt expression (p = 0.030).

Our data allowed us to put forward a hypothesis that high EGFR and low p-Akt expression may predict a clinical benefit of EGFR antagonists such as nimotuzumab combined with RT or CRT. This can be discussed in the terms of oncogene addiction and synthetic lethality concepts. This hypothesis can be further tested in larger groups of patients.

Prognostic impact of KRAS mutant type and MET amplification in metastatic and recurrent gastric cancer patients treated with first-line S-1 plus cisplatin chemotherapy

Receptor tyrosine kinase (RTK)-related genes, including HER2, EGFR, MET, FGFR2 and KRAS, are target molecules that are clinically beneficial in gastric cancer (GC). We investigated the correlation between RTK-related genes and the curative effect of first-line S-1 plus cisplatin (SP) combination chemotherapy in metastatic and recurrent GC. We enrolled 150 patients with histopathologically confirmed metastatic and recurrent GC treated with SP. KRAS mutation was detected using direct sequencing. DNA copy number was measured by real-time PCR. Formalin-fixed paraffin-embedded specimens were examined immunohistochemically for HER2, EGFR, FGFR2 and MET. Among 144 patients, KRAS mutation was detected in five (3.5%) at codon 12 and one (0.7%) at codon 13. FGFR2, EGFR, HER2, MET and KRAS gene amplification was suggested in 4.4%, 5.9%, 9%, 3.7% and 10.3% of patients, respectively. KRAS mutation, but not KRAS amplification, was associated with significantly shorter overall and progression-free survival. MET membranous overexpression was associated with a significantly higher tumor response. MET amplification was associated with significantly shorter overall survival. We show for the first time that KRAS mutation and MET amplification are promising predictive markers in metastatic and recurrent GC patients treated with SP. KRAS status may be a useful prognostic marker in patients treated with SP.

Prognostic significance and frequency of EGFR expression and amplification in surgically resected advanced gastric cancer

OBJECTIVE

The aim of this study is to find the frequency and the role of epidermal growth factor receptor expression as a prognostic biomarker in gastric cancer.

METHODS

We evaluated the prognostic value and frequency of epidermal growth factor receptor expression and amplification using immunohistochemistry and silver in situ hybridization in a large cohort of curatively resected gastric cancer.

RESULTS

Of the total of 935 cases, 294 (31.4%), 101 (10.8%) and 36 (3.9%) patients showed epidermal growth factor receptor 1+, 2+ and 3+ expression on immunohistochemistry, respectively. Epidermal growth factor receptor-positive (2+/3+) patients more frequently had intestinal type than epidermal growth factor receptor-negative (0/1+) patients (82.5 vs. 44.1%, P < 0.001). After adjusting for sex, age, stage and adjuvant chemotherapy, epidermal growth factor receptor-positive patients had a favorable overall survival outcome compared with epidermal growth factor receptor-negative patients (hazard ratio, 0.734; 95% confidence interval, 0.541-0.997; P = 0.047), especially in Stage III disease (hazard ratio, 0.676; 95% confidence interval, 0.472-0.968; P = 0.033). Among the 393 cases available for  in situ hybridization, the correlation between immunohistochemistry and in situ hybridization was statistically significant (P = 0.001). Thirteen patients with gene amplification (3.3%) did not show different survival outcome with others (P = 0.359).

CONCLUSION

Epidermal growth factor receptor positivity was an independent favorable prognostic factor for gastric cancer, especially in Stage III disease.

Targeted therapies in gastric cancer treatment: where we are and where we are going

Gastric cancer (GC) is one of the most common malignancies and a major cause of cancer-related deaths worldwide. Its incidence has significantly declined over the last few decades, probably due to the identification of specific etiologic agents such as Helicobacter pylori and other dietary and environmental risk factors. Nevertheless, most of the cases are unfortunately diagnosed at an advanced stage justifying median overall survival rates frequently not exceeding one year. Palliative combination chemotherapy usually represented by a platinum-based doublet is the mainstay of treatment in the metastatic setting. Adding a third drug such as an anthracycline or a taxane has been shown to improve response rate and provide limited survival benefits in fit selected patients. Unlike other tumors, the introduction of molecularly targeted drugs in the medical armamentarium for GC is relatively recent with trastuzumab and ultimately ramucirumab constituting the only agents approved to date. Recent advances in the understanding of GC biology have led to the development of novel targeted therapies holding the promise to further improve treatment outcomes. The aim of this paper is to review the main available data coming from clinical trials of targeted drugs and to describe some of the most interesting molecules in clinical development in GC. These include drugs targeting EGFR, angiogenesis, c-MET, FGFR2, mTOR and immune checkpoints.