Trastuzumab Combined With Ramucirumab and Paclitaxel in Patients With Previously Treated Human Epidermal Growth Factor Receptor 2-Positive Advanced Gastric or Gastroesophageal Junction Cancer

PURPOSE

Trastuzumab-containing chemotherapy is the recommended first-line regimen for human epidermal growth factor receptor 2 (HER2)-positive advanced gastric or gastroesophageal junction (G/GEJ) cancer. We evaluated the safety and efficacy of trastuzumab combined with ramucirumab and paclitaxel as second-line treatment for HER2-positive G/GEJ cancer.

PATIENTS AND METHODS

Patients with HER2-positive advanced G/GEJ cancer who progressed after first-line treatment with trastuzumab-containing chemotherapy were enrolled from five centers in the Republic of Korea. Patients were administered a 28-day cycle of trastuzumab (once on days 1, 8, 15, and 22: 2 mg/kg followed by 4 mg/kg loading dose), ramucirumab (once on days 1 and 15: 8 mg/kg), and paclitaxel (once on days 1, 8, and 15: dose level 1, 80 mg/m2; or dose level -1, 70 mg/m2). Phase II was conducted with the recommended phase II dose (RP2D). Primary end points were determination of RP2D during phase Ib and investigator-assessed progression-free survival (PFS) in patients treated with RP2D.

RESULTS

Dose-limiting toxicity at dose level 1 was not documented during phase Ib, and a full dose combination was selected as the RP2D. Among 50 patients with a median follow-up duration of 27.5 months (95% CI, 17.4 to 37.6), median PFS and overall survival were 7.1 months (95% CI, 4.8 to 9.4) and 13.6 months (95% CI, 9.4 to 17.7), respectively. Objective response rate was 54% (27 of 50, including one complete response), and disease control rate was 96% (48 of 50). Loss of HER2 expression was observed in 34.8% (8 of 23) patients after first-line treatment, and no definite association between HER2 expression and the outcome was revealed. Safety profiles were consistent with previous reports.

CONCLUSION

Trastuzumab combined with ramucirumab and paclitaxel showed appreciable efficacy with manageable safety profiles in patients with previously treated HER2-positive G/GEJ cancer.

Evaluation and mechanism of immune enhancement effects of Pleurotus ferulae polysaccharides-gold nanoparticles

We previously demonstrated that Pleurotus ferulae polysaccharide (PFPS) promoted dendritic cell (DC) maturation through the TLR4 signaling pathway. To improve PFPS activity and bioavailability, gold nanoparticles with PFPS (PFPS-Au NPs) were synthesized. Of note, although the polysaccharide content of PFPS-Au NPs was only one tenth of PFPS, PFPS-Au NPs enhanced the immunostimulatory activities of PFPS in the maturation and function of dendritic cells (DCs) by TLR4 and NLRP3 signaling pathways, evidenced by stronger activation of the down-stream MAPK and NF-κB pathways and NLRP3 inflammasome pathway. More importantly, PFPS-Au NPs enhanced DC migration and murine immunity, particularly in type 1 T-helper cell responses. Moreover, the half-life of PFPS-Au NPs (2.217 ± 0.187 h) was longer than that of PFPS (1.39 ± 0.257 h) in the blood and the distribution of PFPS-Au NPs (19.8 %) in the spleen was significantly increased compared with PFPS (13.3 %), indicating the improved bioavailability in vivo. PFPS-Au NPs as an adjuvant promoted antigen-specific cellular immune responses to an HPV DC-based vaccine, which significantly inhibited the growth of TC-1 tumors in mice. All results suggest that the prepared Au NPs could enhance PFPS-immunostimulatory activity, which will pave the way for PFPS-Au NPs to be applied in clinical trials.

Glycosoaminoglycans in cancer therapy

Glycosaminoglycans (GAGs) are an important component of the tumor microenvironment (TME). GAGs can interact with a variety of binding partners and thereby influence cancer progression on multiple levels. GAGs can modulate growth factor and chemokine signaling, invasion and metastasis formation. Moreover, GAGs are able to change the physical property of the extracellular matrix (ECM). Abnormalities in GAG abundance and structure (e.g., sulfation patterns and molecular weight) are found across various cancer types and show biomarker potential. Targeting GAGs, as well as the usage of GAGs and their mimetics, are promising approaches to interfere with cancer progression. In addition, GAGs can be used as drug and cytokine carriers to induce an anti-tumor response. In this review, we summarize the role of GAGs in cancer and the potential use of GAGs and GAG derivatives to target cancer.

Emerging HER2-directed therapeutic agents for gastric cancer in early phase clinical trials

INTRODUCTION

HER2 positive gastric cancer is a distinct subgroup overexpressing the HER2 receptor. For a decade, first-line Trastuzumab was the only licensed HER2-directed therapy for HER2 positive advanced gastric cancer following results from the ToGA trial in 2010 demonstrating a survival benefit when added to chemotherapy. Within the last year, significant advances have taken place in the field of HER2-directed gastric cancer therapy.

AREAS COVERED

This review discusses pivotal clinical trial results and summarises current clinical trials of HER2-directed therapy in gastric cancer. Evidence for HER2-directed antibodies, immunotherapy, immune stimulating antibody conjugates, antibody-drug conjugates (including DESTINY trial results) and tyrosine kinase inhibitors are placed into clinical context. Key challenges including resistance mechanisms and drug toxicities are outlined. Search terms 'HER2' and 'gastric cancer' were entered into ClinicalTrials.gov, Pubmed and Google. Only English-language studies were included.

EXPERT OPINION

Clinical management of HER2 positive gastric cancer patients is likely to change significantly over the next 5 years. Checkpoint inhibition is likely to be used alongside HER2-directed therapy and chemotherapy first-line in advanced disease. Trastuzumab deruxtecan is likely to be offered second-line and beyond. The sheer number of clinical trials of HER2-directed therapy in gastric cancer are testament to progress and potential.

TLRs as a Promise Target Along With Immune Checkpoint Against Gastric Cancer

Gastric cancer (GC) is one of the most common cancers in the world, and the incidence of gastric cancer in Asia appears to increase in recent years. Although there is a lot of improvement in treatment approaches, the prognosis of GC is poor. So it is urgent to search for a novel and more effective treatment to improve the survival rate of patients. Both innate immunity and adaptive immunity are important in cancer. In the innate immune system, pattern recognition receptors (PRRs) activate immune responses by recognizing pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). Toll-like receptors (TLRs) are a class of pattern recognition receptors (PRRs). Many studies have reported that TLRs are involved in the occurrence, development, and treatment of GC. Therefore, TLRs are potential targets for immunotherapy to gastric cancer. However, gastric cancer is a heterogeneous disorder, and TLRs function in GC is complex. TLRs agonists can be potentially used not only as therapeutic agents to treat gastric cancer but also as adjuvants in conjunction with other immunotherapies. They might provide a promising new target for GC treatment. In the review, we sort out the mechanism of TLRs involved in tumor immunity and summarize the current progress in TLRs-based therapeutic approaches and other immunotherapies in the treatment of GC.

Systemic therapy of advanced hepatocellular carcinoma

For a decade, sorafenib remained the only approved first-line treatment and standard of care for advanced hepatocellular carcinoma. The treatment landscape has been evolving rapidly over the past 2 years with the approval of additional first-and second-line systemic treatments, most of which are targeted therapies. The expected approval of immunotherapies constitutes a paradigm shift: for the first time in years, a checkpoint inhibitor in combination with a VEGF antibody recently outperformed sorafenib with regards to efficacy. The wider availability of systemic therapies increases the chance for longer overall survival but raises new questions concerning the role of local options, treatment choice and sequential treatment. Following an expert discussion at the German Cancer Congress 2020 in Berlin, this article aims to summarize the current evidence on and experience of treatment choice and sequence in first- and second-line therapy.

Salvage systemic therapy for advanced gastric and oesophago-gastric junction adenocarcinoma

BACKGROUND

Salvage systemic therapy has become the new standard of care in patients with advanced gastric and oesophago-gastric junction (OGJ) adenocarcinoma, following disease progression on first-line fluoropyrimidine and platinum-containing chemotherapy. Pharmacological agents proven to be effective in this setting include both chemotherapy and biological therapy, however, the consensus on the best salvage systemic therapy has not been reached.

OBJECTIVES

To assess the effects of systemic chemotherapy and biological therapy, either alone or in combination, on overall survival (OS) and progression-free survival (PFS) in patients with advanced gastric and OGJ adenocarcinoma, whose disease has progressed on, or relapsed after first-line fluoropyrimidine and platinum-containing chemotherapy. Adverse events (AEs), tumour response rate (TRR) and quality of life (QoL) associated with systemic chemotherapy and/or biological therapy were additionally assessed.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, trial registries and proceedings of the major oncology conferences up to October 2020. We additionally handsearched the reference lists of studies. No language restriction was applied.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing salvage systemic therapy (chemotherapy and/or biological therapy) and either another type of salvage systemic therapy, placebo, best supportive care (BSC) or no treatment in patients with gastric and OGJ adenocarcinoma refractory to first-line fluoropyrimidine and platinum-containing chemotherapy.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed selection of eligible studies and the primary author extracted study characteristics and outcome data from included studies. We assessed the quality and risk of bias of eligible studies according to the Cochrane Handbook for Systematic Reviews of Interventions. We expressed pooled estimates of effect using hazard ratio (HR) calculated using an inverse variance random-effects model for time-to-event data, and risk ratio (RR) calculated using Mantel-Haenszel random-effects model for binary data. The certainty of evidence was graded using GRADEpro.

MAIN RESULTS

We identified 17 RCTs with 5110 participants for inclusion in this review. Tweenty-nine studies are ongoing and twenty studies are awaiting classification. No studies examined the following comparisons: chemotherapy combined with biological therapy versus placebo, BSC or no treatment, chemotherapy combined with biological therapy versus biological therapy, biological therapy versus biological therapy and chemotherapy combined with biological therapy versus chemotherapy combined with biological therapy. Chemotherapy versus placebo, best supportive care or no treatment Chemotherapy probably improves OS (HR = 0.66, 95% CI 0.52 to 0.83, moderate-certainty evidence) based on two studies involving 547 participants and improves PFS (HR = 0.57, 95% CI 0.47 to 0.69, high-certainty evidence) based on one study involving 507 participants over placebo and BSC. Chemotherapy probably increases serious AEs (SAEs) (RR = 1.38, 95% CI 1.20 to 1.59, moderate-certainty evidence) based on one study involving 503 participants. Biological therapy versus placebo, best supportive care or no treatment Biological therapy improves OS (HR = 0.55, 95% CI 0.41 to 0.73, high-certainty evidence) and probably improves PFS (HR = 0.33, 95% CI 0.19 to 0.57, moderate-certainty evidence) over placebo based on three studies involving 781 participants. There is currently insufficient evidence for increased SAEs from biological therapy (RR = 1.14, 95% CI 0.95 to 1.37, low-certainty evidence) based on two studies involving 638 participants. Chemotherapy versus biological therapy This comparison only considered immunotherapy. There is probably no evidence of a difference for OS (HR = 0.82, 95% CI 0.66 to 1.02, moderate-certainty evidence) between chemotherapy and immunotherapy, and immunotherapy probably reduces PFS (HR = 1.27, 95% CI 1.03 to 1.57, moderate-certainty evidence) based on one study involving 395 participants. SAEs may be less frequent with immunotherapy compared to chemotherapy (RR = 0.41, 95% CI 0.30 to 0.57, low-certainty evidence). Chemotherapy combined with biological therapy versus chemotherapy Addition of biological therapy to chemotherapy probably does not improve OS (HR = 0.93, 95% CI 0.83 to 1.04, moderate-certainty evidence) and we are uncertain whether it improves PFS (HR = 0.87, 95% CI 0.74 to 1.02, very low-certainty evidence) based on seven studies involving 2743 participants. We are similarly uncertain whether combined chemotherapy and biological therapy increases SAEs (RR = 1.17, 95% CI 0.95 to 1.44, very low-certainty evidence) based on four studies involving 1618 participants. Chemotherapy versus chemotherapy There is no evidence of a difference for OS and PFS between irinotecan and paclitaxel (HR = 1.13, 95% CI 0.86 to 1.48, low-certainty evidence for OS; HR = 1.14, 95% CI 0.88 to 1.48, low-certainty evidence for PFS) based on one study involving 219 participants. Similarly, there is no evidence to indicate improved OS and PFS from addition of another chemotherapy to docetaxel (HR = 1.05, 95% CI 0.72 to 1.54, low-certainty evidence for OS; HR = 0.75, 95% CI 0.52 to 1.09, low-certainty evidence for PFS) based on two studies involving 121 participants. Grade ≥ 3 neutropenia occurred commonly with both mono- and poly-chemotherapy except for docetaxel-S1 and EOX chemotherapy.

AUTHORS' CONCLUSIONS

Survival outcome of patients with advanced gastric and OGJ adenocarcinoma whose disease progressed on first-line fluoropyrimidine and platinum-containing chemotherapy can be improved by chemotherapy and biological therapy. Biological therapy, in particular, achieves this without clear increase in SAEs or QoL impairment. Whether biological therapy is preferred over chemotherapy is still unclear and there is no evidence of a difference for OS outcome, although immunotherapy may be associated with less SAEs. Addition of biological therapy to chemotherapy and poly-chemotherapy are associated with frequent treatment-related toxicity without clear survival benefit.

Biomarkers for Precision Treatment in Gastric Cancer

BACKGROUND

Gastric cancer (GC) is one of the most lethal cancers worldwide. Although GC was historically considered a single entity within the organ of origin, nowadays it is acknowledged that GC represents a heterogeneous disease. Nevertheless, in this field there is still a lack of biomarkers able to guide the choice of the best treatment options for each patient. This review aims to summarize the prognostic and predictive biomarkers evaluated in GC and their role as a guide for treatment for precision medicine.

SUMMARY

Human epidermal growth factor receptor 2 overexpression represents the only predictive molecular biomarker validated in GC, while its prognostic role is still controversial. Microsatellite instability and Epstein-Barr virus status are promising for prediction of the response to immunotherapy. The role of other biomarkers (ctDNA, programmed death ligand 1 [PD-L1], and TMB), as well as the practical application of molecular classifications, requires further evaluation before use in clinical practice. 18-FDG-PET scan could be useful as a predictive tool in non-metastatic GC patients receiving a perioperative approach. Finally, the tumor microenvironment may have an evolving role in the future.

KEY MESSAGES

GC is a heterogeneous disease and targeted approaches are needed. The finding of prognostic and predictive factors is a hot topic in the field of GC personalized medicine.

PD-L1 and HER2 Expression in Gastroesophageal Cancer: a Matched Case Control Study

Immunotherapy with check-point inhibitors serves as a promising treatment strategy in patients with upper gastrointestinal (GI) tumors. Human epidermal growth factor receptor 2 (HER2) is the only identified therapeutic target in upper GI tumors, whose potential interaction with programmed death-ligand 1 (PD-L1) is unknown. The aim of this study was the investigation of PD-L1 and HER2 in upper GI tumors. We retrospectively identified patients with HER2 positive gastroesophageal cancers and matched them with a HER2 negative group. We investigated the tumor specimens for HER2 status and PD-L1 expression, with the following assessments being performed: i) staining of tumor cells in terms of tumor proportion score (TPS), ii) staining for tumor-associated immune cells (TAIs), iii) interface pattern and iv) combined positive score (CPS). Both HER2 positive and negative group consisted of 59 patients. Expression of PD-L1 in TAIs and interface pattern were associated with a favorable outcome (p = 0.02, HR = 0.8; p = 0.04, HR = 0.39; respectively) in patients with localized disease, whereas TPS was associated with an unfavorable outcome in patients with advanced tumor (p = 0.02, HR = 1.4). These effects were HER2 independent. PD-L1 expression in its different assessment is equally observed in HER2 positive and negative patients. Future studies will show whether dual inhibition of HER2 and PD-L1 improves survival of this selected patient population.

Optimization of perioperative approaches for advanced and late stages of gastric cancer: clinical proposal based on literature evidence, personal experience, and ongoing trials and research

BACKGROUND

The high incidence of gastric cancer (GC) and paradoxical high prevalence of advanced stage GC, amounting to around 2/3 at time of diagnosis, have urged doctors and researchers around the world not only to ameliorate the detection rate of GC at early stages but also to optimize the clinical management of GC at advanced stages.

CONTENT

We hereby recommend a more goal-oriented multimodality approach with objectives to increase survival rate and improve survival status. Based on precision and accurate clinical staging at diagnosis, we suggest that advanced stage GC (AGC) patients should be channeled into different treatment plans according to their disease status where they can be subjected to comprehensive measures involving chemo, radio, immunological, or target therapies depending on the pathophysiological behavior of their tumor. Patients assessed as potentially resectable cT4N + M0 can undergo neoadjuvant chemotherapy with intent of tumor downsizing and downgrading followed by surgery with intraoperative hyperthermic intraperitoneal chemotherapy (HIPEC) to decrease the incidence of peritoneal dissemination due to surgical trauma and adjuvant chemotherapy and radiation in cases of bulky nodal metastasis. In cases with distal metastasis, conversion therapy is recommended with the possibility of surgery of curative intent in case of favorable response. The options of alternate treatment options such as trans-catheter arterial chemoembolization (TACE) for limited liver lesions or neoadjuvant intraperitoneal plus systemic chemotherapy (NIPS) for peritoneal carcinomatosis have to be negotiated. With surgery as the cornerstone for cancer treatment, there is acknowledgment of the significance of perioperative comprehensive approaches but there has not been some consensus guiding clinical application. Henceforth, in this review, based on past literature, current guidelines and ongoing clinical trials, we have shared a proposal of the current treatment modalities in practice for the advanced stages of gastric cancer.

CONCLUSION

Even though surgery is the golden standard of radical cancer treatment, clinical reality shows that without proper perioperative management, patients undergoing radical resections manifest high rates of recurrence and metastasis. Hence, in this review, we have outlined a clinical agenda to optimize the management of advanced stage GC with objective to improve survival outcome and quality of life of patients.

Exploratory subgroup analysis of patients with prior trastuzumab use in the ATTRACTION-2 trial: a randomized phase III clinical trial investigating the efficacy and safety of nivolumab in patients with advanced gastric/gastroesophageal junction cancer

BACKGROUND

Data on immune checkpoint inhibitor efficacy in patients with human epidermal growth factor receptor 2-positive (HER2+) advanced gastric/gastroesophageal junction (G/GEJ) cancer are lacking. Because HER2 status was not captured in the ATTRACTION-2 trial, we used patients with prior trastuzumab use (Tmab+) as surrogate for HER2 expression status to evaluate the efficacy and safety of nivolumab as third- or later-line therapy in these patients.

METHODS

In ATTRACTION-2, a randomized, double-blind, placebo-controlled, phase 3 multicenter trial, patients were randomized (2:1) to receive nivolumab (3 mg/kg) or placebo every 2 weeks until disease progression or toxicity requiring study discontinuation. Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and safety were assessed.

RESULTS

Of 493 enrolled patients, 81 (nivolumab, n = 59; placebo, n = 22) were Tmab+ and 412 (nivolumab, n = 271; placebo, n = 141) were Tmab-. In both groups, patients receiving nivolumab showed a longer median OS vs placebo (Tmab+, 8.3 [95% confidence interval, 5.3-12.9] vs 3.1 [1.9-5.3] months, hazard ratio, 0.38 [0.22-0.66]; P = 0.0006; Tmab-, 4.8 [4.1-6.0] vs 4.2 [3.6-4.9] months, 0.71 [0.57-0.88]; P = 0.0022). PFS was longer in both groups receiving nivolumab vs placebo (Tmab+, 1.6 [1.5-4.0] vs 1.5 [1.3-2.9] months, 0.49 [0.29-0.85]; P = 0.0111; Tmab-, 1.6 [1.5-2.4] vs 1.5 [1.5-1.5] months, 0.64 [0.51-0.80]; P = 0.0001).

CONCLUSIONS

Nivolumab was efficacious and safe as third- or later-line therapy regardless of prior trastuzumab use in patients with advanced G/GEJ cancer.

Safety and Efficacy of the Addition of Lapatinib to Perioperative Chemotherapy for Resectable HER2-Positive Gastroesophageal Adenocarcinoma: A Randomized Phase 2 Clinical Trial

IMPORTANCE

Perioperative chemotherapy and surgery are a standard of care for operable gastroesophageal adenocarcinoma. Anti-HER2 therapy improves survival in patients with advanced HER2-positive disease. The safety and feasibility of adding lapatinib to perioperative chemotherapy should be assessed.

OBJECTIVES

To assess the safety of adding lapatinib to epirubicin, cisplatin, and capecitabine (ECX) chemotherapy and to establish a recommended dose regimen for a phase 3 trial.

DESIGN, SETTING, AND PARTICIPANTS

Phase 2 randomized, open-label trial comparing standard ECX (sECX: 3 preoperative and 3 postoperative cycles of ECX with modified ECX plus lapatinib (mECX+L). This multicenter national trial was conducted in 29 centers in the United Kingdom in patients with histologically proven, HER2-positive, operable gastroesophageal adenocarcinoma. Registration for ERBB/HER2 testing took place from February 25, 2013, to April 19, 2016, and randomization took place between May 24, 2013, and April 21, 2016. Data were analyzed May 10, 2017, to May 25, 2017.

INTERVENTIONS

Patients were randomized 1:1 open-label to sECX (3 preoperative and 3 postoperative cycles of 50 mg/m2 of intravenous epirubicin on day 1, 60 mg/m2 intravenous cisplatin on day 1, 1250 mg/m2 of oral capecitabine on days 1 through 21) or mECX+L (ECX plus lapatinib days 1 through 21 in each cycle and as 6 maintenance doses). The first 10 patients in the mECX+L arm were treated with 1000 mg/m2 of capecitabine and 1250 mg of lapatinib per day, after which preoperative toxic effects were reviewed according to predefined criteria to determine doses for subsequent patients.

MAIN OUTCOMES AND MEASURES

Proportion of patients experiencing grade 3 or 4 diarrhea with mECX+L. A rate of 20% or less was considered acceptable. No formal comparison between arms was planned.

RESULTS

Between February 2013, and April 2016, 441 patients underwent central HER2 testing and 63 (14%) were classified as HER2 positive. Forty-six patients were randomized; 44 (24 sECX, 20 mECX+L) are included in this analysis. Two of the first 10 patients in the mECX+L arm reported preoperative grade 3 diarrhea; thus, no dose increase was made. The primary endpoint of preoperative grade 3 or 4 diarrhea rates were 0 of 24 in the sECX arm (0%) and 4 of 20 in the mECX+L arm (21%). One of 24 in the sECX arm and 3 of 20 in the mECX+L arm stopped preoperative treatment early, and for 4 of 19 in the mECX+L arm, lapatinib dose was reduced. Postoperative complication rates were similar in each arm.

CONCLUSIONS AND RELEVANCE

Administration of 1250 mg of lapatinib per day in combination with ECX chemotherapy was feasible with some increase in toxic effects, which did not compromise operative management.

TRIAL REGISTRATION

ISRCTN.org identifier: 46020948; clinicaltrialsregister.eu identifier: 2006-000811-12.

Identification of genomic features associated with immunotherapy response in gastrointestinal cancers

Gastrointestinal (GI) cancers prevail and account for an extremely high number of cancer deaths worldwide. The traditional treatment strategies, including surgery, chemotherapy, radiotherapy, and targeted therapy, have a limited therapeutic effect for advanced GI cancers. Recently, immunotherapy has shown promise in treating various refractory malignancies, including the GI cancers with mismatch repair deficiency (dMMR) or microsatellite instability (MSI). Thus, immunotherapy could be a promising treatment approach for GI cancers. Unfortunately, only a small proportion of GI cancer patients currently respond to immunotherapy. Therefore, it is important to discover predictive biomarkers for stratifying GI cancer patients response to immunotherapy. Certain genomic features, such as dMMR/MSI, tumor mutation burden (TMB), and tumor aneuploidy have been associated with tumor immunity and im-munotherapy response and may serve as predictive biomarkers for cancer immunotherapy. In this review, we examined the correlations between tumor immunity and three genomic features: dMMR/MSI, TMB, and tumor aneuploidy. We also explored their correlations using The Cancer Genome Atlas data and confirmed that the dMMR/MSI status, high TMB, and low tumor aneuploidy are associated with elevated tumor immunity in GI cancers. To improve the immunotherapeutic potential in GI cancers, more genetic or genomic features associated with tumor immune response need to be identified. Furthermore, it is worth exploring the combination of different immunotherapeutic methods and the combination of immunotherapy with other therapeutic approaches for cancer therapy.

The landscape of d16HER2 splice variant expression across HER2-positive cancers

The HER2 splice variant characterized by the deletion of exon 16 and denominated as d16HER2, is associated with HER2-positive breast cancer (BC) aggressiveness, stemness, and trastuzumab susceptibility and is considered to be a “flag” of HER2 dependence. However, with the exception of quantitative real-time PCR analysis, easily reproducible assays are still lacking to clinically detect and quantify the d16HER2 expression. Further, no data on d16HER2 expression and its potential role are available in HER2-positive gastrointestinal malignancies. Here, we used a novel RNA in situ hybridization technique (BaseScope) to discriminate d16HER2 variant expression from the wild type isoform (WTHER2) and to assess their levels across different HER2-positive histological samples. Our results demonstrate the existence of outliers, with d16HER2 mRNA high scores restricted to HER2-positive gastric cancer (GC) and colorectal cancer (CRC) coupled with increased d16HER2 expression compared with BC. Consistent with previously reported data on BC, experiments performed in HER2-positive GC patient-derived xenografts suggest that increased d16HER2 expression is associated with a clinical benefit/response to single-agent trastuzumab. Therefore, d16HER2 may be considered as a “flag” of HER2 dependence in GC and can be clinically investigated as a marker of trastuzumab susceptibility in several other HER2-driven cancers, including CRC. As a clinical proof-of-concept, we indicate that high d16HER2 mRNA scores are exclusively found in patients with a long-term benefit from trastuzumab exceeding 12 months (clinical “outliers”), and that d16HER2 expression is also increased in circulating tumor-released exosomes obtained from baseline plasma samples of long-term responders.

Clinical significance of intratumoral HER2 heterogeneity on trastuzumab efficacy using endoscopic biopsy specimens in patients with advanced HER2 positive gastric cancer

BACKGROUND

We recently reported the clinical significance of intratumoral HER2 heterogeneity on trastuzumab efficacy using surgical specimens; patients with homogeneously HER2 positive gastric cancer benefitted more from trastuzumab. However, the majority of patients are diagnosed by endoscopic biopsy, and surgical specimens are not available in these patients. The aim of this study is to verify clinical significance of HER2 heterogeneity on trastuzumab efficacy using biopsy specimens.

METHODS

Eighty-seven patients, who received trastuzumab-based chemotherapy and whose endoscopic biopsy specimens were available for HER2 assessment, were consecutively enrolled. When all tumor cells in all biopsy specimens overexpressed HER2 protein, it was defined as homogeneously HER2 (homo-HER2) positive group, and the others were defined as heterogeneously HER2 (hetero-HER2) positive group. Progression-free survival (PFS), overall survival (OS) and objective response rate (ORR) were evaluated.

RESULTS

Thirty-four patients (39%) were diagnosed as the homo-HER2 group and 53 patients (61%) were the hetero-HER2 group. After the median follow-up period of 17.8 months, the median PFS and OS were 7.6 and 17.8 months, respectively. Significant survival differences were shown between the two groups; the homo-HER2 group showed significantly longer PFS (10.8 vs. 6.1 months, HR 0.469 95% CI 0.29-0.77, p = 0.003) and OS (29.3 vs. 14.4 months, HR 0.352 95% CI 0.20-0.61, p < 0.001). ORR was 68.6% in this cohort. Higher response rate (85.2% vs 58.1%, p = 0.020) and deeper response (- 49.0% vs - 40.0%, p = 0.018) were also found in the homo-HER2 group.

CONCLUSIONS

Similar to surgical specimens, we verified clinical significance of HER2 heterogeneity on trastuzumab efficacy using endoscopic biopsy specimens.

NRF2 through RPS6 Activation Is Related to Anti-HER2 Drug Resistance in HER2-Amplified Gastric Cancer

PURPOSE

Despite the clinical advantage of the combination of trastuzumab and platinum-based chemotherapy in HER2-amplified tumors, resistance will eventually develop. The identification of molecular mechanisms related to primary and acquired resistance is needed.

EXPERIMENTAL DESIGN

We generated lapatinib- and trastuzumab-resistant clones deriving from two different HER2-amplified gastric cancer cell lines. Molecular changes such as protein expression and gene-expression profile were evaluated to detect alterations that could be related to resistance. Functional studies in vitro were corroborated in vivo. The translational relevance of our findings was verified in a patient cohort.

RESULTS

We found RPS6 activation and NRF2 to be related to anti-HER2 drug resistance. RPS6 or NRF2 inhibition with siRNA reduced viability and resistance to anti-HER2 drugs. In knockdown cells for RPS6, a decrease of NRF2 expression was demonstrated, suggesting a potential link between these two proteins. The use of a PI3K/TORC1/TORC2 inhibitor, tested in vitro and in vivo, inhibited pRPS6 and NRF2 expression and caused cell and tumor growth reduction, in anti-HER2-resistant models. In a cohort of HER2-amplified patients treated with trastuzumab and chemotherapy, a high level of NRF2 at baseline corresponds with worse progression-free survival.

CONCLUSIONS

NRF2 through the PI3K/AKT/mTOR/RPS6 pathway could be a potential effector of resistance to anti-HER2 drugs in our models. RPS6 inhibition decreases NRF2 expression and restores sensitivity in HER2-amplified gastric cancer in vitro and in vivo. High NRF2 expression in gastric cancer patients predicts resistance to treatment. RPS6 and NRF2 inhibition could prevent resistance to anti-HER2 drugs.

Clinical efficacy of intraperitoneal hyperthermic perfusion chemotherapy for patients with gastric cancer peritoneal metastasis: Impact on immune function and prognosis

AIM

To evaluate the clinical efficacy of intraperitoneal hyperthermic perfusion chemotherapy for patients with gastric cancer (GC) peritoneal metastasis and its impact on immune function and prognosis.

METHODS

A retrospective analysis was performed of 113 patients with GC treated at the First Affiliated Hospital of Zhengzhou University between June 2010 and March 2013. The patients were randomly divided into an observation group (54 cases) and a control group (59 cases). Patients in the control group were treated with conventional intravenous chemotherapy, and patients in the observation group were treated with intraperitoneal hyperthermic perfusion chemotherapy. The clinical efficacy, related indicators of recurrence and metastasis, tumor markers, T-lymphocyte subsets, quality of life, and occurrence of adverse reactions after chemotherapy was compared between the two groups of patients.

RESULTS

The total effective rate and disease control rate in the observation group were significantly higher than those in the control group (P < 0.05). The levels of serum carbohydrate antigen 199 (CA199), CA724, and carcinoembryonic antigen (CEA) were significantly lower in the observation group than in the control group (P < 0.05). After treatment, serum vascular endothelial growth factor (VEGF), osteopontin (OPN), soluble apoptotic factor (sFas), and matrix metalloproteinase-9 (MMP-9) levels were significantly lower in the observation group than in the control group (P < 0.05). CD3⁺ T cells, CD4⁺ T cells, CD4⁺/CD8⁺ ratio, and B cells in the peripheral blood were significantly higher in the observation group than in the control group, while CD8⁺ T cells and NK cells were significantly lower than those of the control group (P < 0.05). The improvement of KPS score after treatment, the recurrence rate at 2 years, the 3-year survival rate, and the 5-year survival rate were significantly better in the observation group than in the control group (P < 0.05). The incidence of adverse reactions after chemotherapy was not statistically different between the two groups (P > 0.05).

CONCLUSION

Peritoneal hyperthermic perfusion chemotherapy can improve clinical efficacy, tumor markers and related indicators of recurrence and metastasis, as well as the patient's immune function and quality of life of patients with GC peritoneal metastasis, without increasing the incidence of adverse reactions.

New drug developments in metastatic gastric cancer

Metastatic gastric cancer is associated with a poor prognosis and novel treatment options are desperately needed. The development of targeted therapies heralded a new era for the management of metastatic gastric cancer, however results from clinical trials of numerous targeted agents have been mixed. The advent of immune checkpoint inhibitors has yielded similar promise and results from early trials are encouraging. This review provides an overview of the systemic treatment options evaluated in metastatic gastric cancer, with a focus on recent evidence from clinical trials for targeted therapies and immune checkpoint inhibitors. The failure to identify appropriate predictive biomarkers has hampered the success of many targeted therapies in gastric cancer, and a deeper understanding of specific molecular subtypes and genomic alterations may allow for more precision in the application of novel therapies. Identifying appropriate biomarkers for patient selection is essential for future clinical trials, for the most effective use of novel agents and in combination approaches to account for growing complexity of treatment options.

Clinical impact of intratumoral HER2 heterogeneity on trastuzumab efficacy in patients with HER2-positive gastric cancer

BACKGROUND

There is growing interest in the clinical significance of intratumoral HER2 heterogeneity. Its prognostic and predictive impacts on trastuzumab efficacy were demonstrated in breast cancer. However, its clinical significance in gastric cancer is still unclear.

METHODS

Twenty-eight HER2-positive gastric cancer patients who had gastrectomy prior to trastuzumab-based chemotherapy were consecutively enrolled. Intratumoral HER heterogeneity was evaluated using whole-tissue sections by immunohistochemistry. When all tumor cells overexpressed HER2 protein, the tumor was defined as homogeneously HER2 (Homo-HER2)-positive group. The others were defined as heterogeneously HER2 (Hetero-HER2)-positive group.

RESULTS

There was no significant difference in clinicopathological features between the two groups. The median progression-free survival (PFS) and overall survival (OS) in the Homo-HER2-positive group were significantly longer than those in the Hetero-HER2-positive group (PFS; 20.0 months [95% CI 17.8-22.2] vs. 6.0 months [95% CI 2.3-9.7]; HR 0.11; 95% CI 0.03-0.41; p < 0.001, OS; not reached vs. 14.0 months [95% CI 11.9-16.1]; HR 0.18; 95% CI 0.06-0.61; p = 0.003). In the multivariate analysis, these associations remained significant both in PFS (HR 0.12; 95% CI 0.03-0.46, p = 0.002) and OS (HR 0.21; 95% CI 0.06-0.72, p = 0.013). With respect to response rate, no statistical difference was found between two groups. However, deeper tumor shrinkage was obtained in the Homo-HER2-positive group compared with the Hetero-HER2-positive group (p = 0.046).

CONCLUSIONS

Intratumoral HER2 heterogeneity may have robust clinical impact on trastuzumab efficacy in patients with HER2-positive gastric cancer. These findings should be validated by larger independent cohorts and further molecular correlative analyses are warranted.

Emerging Therapies in the Management of Advanced-Stage Gastric Cancer

Globally, gastric malignancy contributes to significant cancer-related morbidity and mortality. Despite a recent approval of two targeted agents, trastuzumab and ramucirumab, the treatment options for advanced-stage gastric cancer are limited. Consequently, the overall clinical outcomes for patients with advanced-stage gastric cancer remain poor. Numerous agents that are active against novel targets have been evaluated in the course of randomized trials; however, most have produced disappointing results because of the molecular heterogeneity of gastric cancer. The Cancer Genome Atlas (TCGA) project proposed a new classification system for gastric cancer that includes four different tumor subtypes based on molecular characteristics. This change led to the identification of several distinct and potentially targetable pathways. However, most agents targeting these pathways do not elicit any meaningful clinical benefit when employed for the treatment of advanced-stage gastric cancer. Most advanced-stage gastric cancer trials currently focus on agents that modulate tumor microenvironments and cancer cell stemness. In this review, we summarize data regarding novel compounds that have shown efficacy in early phase studies and show promise as effective therapeutic agents, with special emphasis on those for which phase III trials are either planned or underway.

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.

Recent updates in perioperative chemotherapy and recurrence pattern of gastric cancer

Gastrectomy with D2 lymph node dissection has become the global standard procedure for locally advanced gastric cancer to maximally reduce locoregional recurrence. In East Asia, based on the evidence of the ACTS‐GC and the CLASSIC trials, postadjuvant chemotherapy with S‐1 monotherapy or capecitabine and oxaliplatin after curative D2 gastrectomy is the current standard strategy. However, approximately 20% to 30% of patients still develop distant recurrence even after these postadjuvant chemotherapies, especially in those with pathological stage III disease. This review summarizes recent (2008‐2018) evidence on the benefits of adjuvant therapy for locally advanced gastric cancer. JACRO GC‐07, a Phase III trial, recently showed a superior 3‐year recurrence‐free survival of the S‐1 plus docetaxel regimen in comparison to S‐1 monotherapy for patients with pathological stage III gastric cancer after curative D2 gastrectomy. With regard to recent new evidence on neoadjuvant strategy, JCOG0501, a Phase III trial, did not show any superiority in 3‐year overall survival (OS) of additional neoadjuvant chemotherapy with S‐1/cisplatin over postadjuvant S‐1 monotherapy in scirrhous type gastric cancer. Further clinical trials of neoadjuvant chemotherapy are ongoing to improve the poor prognosis for gastric cancer with extensive lymph node metastases. These trials could lead to new evidence for improved treatment of gastric cancer in the near future.

Current and future therapies for targeting HER2 mutations in gastrointestinal cancer

INTRODUCTION

Gastrointestinal (GI) cancers altogether represent the most common cancer type. HER2 is found to be present in nearly all histologic types of GI cancers in variable degrees of expression. Over the last decade, substantial advances have been made in targeting HER2-positive cancers. Areas covered: The present review summarizes the current progress and future directions for HER2 targeted therapies in GI cancers, including esophagogastric, pancreaticobiliary, and colon cancers. To date trastuzumab is the only anti-HER2 therapy approved for metastatic esophagogastric adenocarcinoma. Efforts are ongoing to expand the therapeutic role of HER2 to other GI cancers and overcome mechanisms of drug resistance. Novel agents and combinations are being tested in most HER2 positive GI cancers including early stage disease. These are of recent interest in colorectal cancer with studies indicating that HER2 overexpression might increase resistance to anti-EGFR therapy and may be potentially targeted. Expert commentary: With the current ability to sequence tumors and detect genetic alterations, emphasis should be put on genomically-selected pan-tumor targeted therapies. HER2 is a perfect example of a promising drug target in GI cancers.

Intra-Arterial TheraSphere Yttrium-90 Glass Microspheres in the Treatment of Patients With Unresectable Hepatocellular Carcinoma: Protocol for the STOP-HCC Phase 3 Randomized Controlled Trial

BACKGROUND

Globally, hepatocellular carcinoma is the second most common cause of cancer deaths. It remains challenging to intensify cancer treatment without impairing liver function.

OBJECTIVE

The objective of the TheraSphere in the Treatment of Patients with Unresectable Hepatocellular Carcinoma (STOP-HCC) study is to examine the hypothesis that transarterial radioembolization (TheraSphere yttrium-90 glass microspheres) combined with standard first-line treatment with sorafenib will improve outcomes over treatment with sorafenib alone in unresectable hepatocellular carcinoma. The STOP-HCC study is the largest international, multicenter, prospective study of intra-arterial treatment in combination with sorafenib in unresectable hepatocellular carcinoma. Here we report the study design.

METHODS

STOP-HCC is a prospective, phase 3, open-label, randomized controlled study conducted across up to 105 sites in North America, Europe, and Asia. Eligible adults have unresectable hepatocellular carcinoma and a life expectancy of at least 12 weeks, 1 or more unidimensional measurable lesions, Child-Pugh score 7 points or less, and Eastern Cooperative Oncology Group Performance Status score 1 or lower, and are candidates for treatment with sorafenib. Presence of branch portal vein tumor thrombosis is permitted. Patients were randomly assigned in a 1:1 ratio to receive either sorafenib alone or transarterial radioembolization followed by sorafenib within 2 to 6 weeks. The primary outcome is overall survival. Secondary outcomes are time to progression, time to untreatable progression, time to symptomatic progression, tumor response, quality of life, and adverse event occurrence. The study is an adaptive trial, comprising a group-sequential design with 2 interim analyses with 520 patients, and an option to increase the sample size to 700 patients at the second interim analysis. The sample size of 520 patients allows for 417 deaths to give 80% power to detect an increase in median overall survival from 10.7 months for the sorafenib group (based on the Sorafenib Hepatocellular Carcinoma Assessment Randomized Protocol [SHARP] trial) to 14.2 months for the transarterial radioembolization+sorafenib group (hazard ratio 0.754) with 2-sided alpha of .05. The increased sample size of 700 patients allows for 564 deaths to give 80% power to detect a smaller difference in median overall survival from 10.7 months for the sorafenib group to 13.7 months for the transarterial radioembolization+sorafenib group (hazard ratio 0.781).

RESULTS

Enrollment for the study completed in September 2017. Results of the first and second interim analyses were reviewed by the Independent Data Monitoring Committee. The recommendation of the committee, at both interim analyses, was to continue the study without any changes.

CONCLUSIONS

The STOP-HCC study will contribute toward the establishment of the role of combination therapy with transarterial radioembolization and sorafenib in the treatment of unresectable hepatocellular carcinoma with and without branch portal vein tumor thrombosis.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01556490; https://clinicaltrials.gov/ct2/show/NCT01556490 (Archived by WebCite at http://www.webcitation.org/7188iygKs).

REGISTERED REPORT IDENTIFIER

RR1-10.2196/11234.

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.

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.

HER2 inhibition in gastro-oesophageal cancer: A review drawing on lessons learned from breast cancer

Human epidermal growth factor receptor 2 (HER2)-inhibition is an important therapeutic strategy in HER2-amplified gastro-oesophageal cancer (GOC). A significant proportion of GOC patients display HER2 amplification, yet HER2 inhibition in these patients has not displayed the success seen in HER2 amplified breast cancer. Much of the current evidence surrounding HER2 has been obtained from studies in breast cancer, and we are only recently beginning to improve our understanding of HER2-amplified GOC. Whilst there are numerous licensed HER2 inhibitors in breast cancer, trastuzumab remains the only licensed HER2 inhibitor for HER2-amplified GOC. Clinical trials investigating lapatinib, trastuzumab emtansine, pertuzumab and MM-111 in GOC have demonstrated disappointing results and have not yet changed the treatment paradigm. Trastuzumab deruxtecan may hold promise and is currently being investigated in phase II trials. HER2 amplified GOC differs from breast cancer due to inherent differences in the HER2 amino-truncation and mutation rate, loss of HER2 expression, alterations in HER2 signalling pathways and differences in insulin-like growth factor-1 receptor and MET expression. Epigenetic alterations involving different microRNA profiles in GOC as compared to breast cancer and intrinsic differences in the immune environment are likely to play a role. The key to effective treatment of HER2 amplified GOC lies in understanding these mechanisms and tailoring HER2 inhibition for GOC patients in order to improve clinical outcomes.

Molecular biomarkers in gastro-esophageal cancer: recent developments, current trends and future directions

Gastro-esophageal adenocarcinomas (GEA) represent a severe global health burden and despite improvements in the multimodality treatment of these malignancies the prognosis of patients remains poor. HER2 overexpression/amplification has been the first predictive biomarker approved in clinical practice to guide patient selection for targeted treatment with trastuzumab in advanced gastric and gastro-esophageal junction cancers. More recently, immunotherapy has been approved for the treatment of GEA and PD-L1 expression is now a biomarker required for the administration of pembrolizumab in these diseases. Significant progress has been made in recent years in dissecting the genomic makeup of GEA in order to identify distinct molecular subtypes linked to distinct patterns of molecular alterations. GEA have been found to be highly heterogeneous malignances, representing a challenge for biomarkers discovery and targeted treatment development. The current review focuses on an overview of established and novel promising biomarkers in GEA, covering recent molecular classifications from TCGA and ACRG. Main elements of molecular heterogeneity are discussed, as well as emerging mechanisms of primary and secondary resistance to HER2 targeted treatment and recent biomarker-driven trials. Future perspectives on the role of epigenetics, miRNA/lncRNA and liquid biopsy, and patient-derived xenograft models as a new platform for molecular-targeted drug discovery in GEA are presented. Our knowledge on the genomic landscape of GEA continues to evolve, uncovering the high heterogeneity and deep complexity of these tumors. The availability of new technologies and the identification of promising novel biomarker will be critical to optimize targeted treatment development in a setting where therapeutic options are currently lacking. Nevertheless, clinical validation of novel biomarkers and treatment strategies still represents an issue.

Survival in Advanced Esophagogastric Adenocarcinoma Improves With Use of Multiple Lines of Therapy: Results From an Analysis of More Than 500 Patients

BACKGROUND

Although progress has been made in the molecular stratification of esophagogastric adenocarcinoma, the outlook for advanced disease remains poor. The present evaluation of over 500 patients treated at a single European high-volume tertiary center during a 6-year period gives important information on current and developing "real-world" treatment patterns and outcomes.

RESULTS

The overall survival for the whole cohort was 11.5 months, with a range of treatments used in first-, second-, and third-line settings. Treatment with sequential lines of therapy was associated with better outcomes, although only 39% and 14% of patients subsequently received treatment in the second- and third-line setting, respectively. Treatment within a therapeutic clinical trial was associated with significantly improved survival.

CONCLUSION

At present, a substantial proportion of patients with advanced esophagogastric adenocarcinoma will not proceed beyond first-line therapy, and for this group refinement of initial systemic therapies are required to improve outcomes. Although a number of established first- and second-line treatment options are now available, the therapeutic landscape of the disease continues to change, most notably in the application of immunotherapy and increasing interest in establishing evidence-based interventions in the third-line setting and beyond. A small but growing proportion of patients will benefit from sequential treatment approaches incorporating multiple lines of therapy, and improved selection of such patients will be a key challenge for clinicians moving forwards. Data such as these provide an overview of current treatment patterns and outcomes which can be used to inform planning of future research effectively within existing treatment frameworks.

The dynamics of HER2 status in esophageal adenocarcinoma

Trastuzumab, a monoclonal antibody against HER2, has become standard of care for metastatic HER2-overexpressing esophagogastric adenocarcinoma and is currently investigated as (neo)adjuvant treatment option in HER2-positive esophagogastric adenocarcinoma. The HER2 status is commonly determined on archived material of the primary tumor. However, this status may change over the course of treatment or disease progression. The aim of this study was to assess the dynamics of HER2 status in esophageal adenocarcinoma (EAC) in patients with resectable and recurrent disease, and to determine the associations of these changes with clinical outcome. Discordance, defined as any change in HER2 status between matched biopsy and post-neoadjuvant chemoradiation therapy resection specimen (N = 170), or between matched resection specimen and recurrence of patients not eligible for curative treatment (N = 61), was determined using the standardized HER2 status scoring system. Clinically relevant positive discordance was defined as a change to HER2 positive status, as this would imply eligibility for HER2-targeted therapy. A difference in HER2 status between biopsy and resection specimen and resection specimen and metachronous recurrence was observed in 2.1% (n = 3) and 3.3% (n = 2) of the paired cases, respectively. Clinically relevant discordance was detected in 1.4% (n = 2) of the resectable patients and 1.6% (n = 1) of the patients with recurrent disease. Patients with HER2-positive status tumors before start of neoadjuvant treatment showed better overall survival, but not statistically significant. No association between HER2 status discordance and survival was found. Clinically relevant HER2 status discordance was observed and in order to prevent under-treatment of patients, the assessment of HER2 status in the metastatic setting should preferably be performed on the most recently developed lesions if the previous HER2 assessment on archival material of the primary tumor was negative.

Upper gastrointestinal malignancies in 2017: current perspectives and future approaches

The advent of immune checkpoint inhibitors (PD-1, PD-L1 and CTLA-4) has resulted in unprecedented long-term remissions of unresectable cancers. The efficacy of checkpoint inhibitors was recently demonstrated in gastrointestinal malignancies with mismatch repair deficiencies (dMMR). Pembrolizumab became the first tissue-agnostic US FDA-approved drug based on the presence of the predictive biomarker dMMR. In addition, the FDA in 2017 approved pembrolizumab for PD-L1-positive advanced gastric cancer in third-line and second-line hepatocellular therapy. Novel treatment strategies such as using anti-carcinoembryonic antigen (CEA) bispecific T cells have led to remarkable responses in microsatellite instability-low colorectal cancer. Other major breakthroughs in treating upper gastrointestinal malignancies in 2017 are discussed.

Multimodality treatment of operable gastric and oesophageal adenocarcinoma: evaluating neoadjuvant, adjuvant and perioperative approaches

INTRODUCTION

Treatment patterns for locally advanced operable gastric and oesophageal adenocarcinoma vary, with the optimal approach an area of debate within oncology. Strategies for treatment include a variety of neo-adjuvant, adjuvant and peri-operative regimens involving differing chemotherapy and radiotherapy combinations. Areas covered: This review will critically appraise the evidence base underpinning the main treatment approaches in operable oesophagogastric adenocarcinoma, highlighting variations in treatment by factors such as geographical area and primary tumor site. Expert commentary: The expert commentary will focus on the optimal evidence-based approaches for clinicians at the present time and explore how increased understanding of the molecular and genetic determinants of the disease may lead to refinements in treatment through the development of both biomarker-driven approaches and the application of novel targeted and immune-modulating agents to early treatment.

Biomarkers of Primary Resistance to Trastuzumab in HER2-Positive Metastatic Gastric Cancer Patients: the AMNESIA Case-Control Study

Purpose: Refining the selection of HER2-positive metastatic gastric cancer patient candidates for trastuzumab is a challenge of precision oncology. Preclinical studies have suggested several genomic mechanisms of primary resistance, leading to activation of tyrosine kinase receptors other than HER2 or downstream signaling pathways.Experimental Design: We carried out this multicenter, prospective, case-control study to demonstrate the negative predictive impact of a panel of candidate genomic alterations (AMNESIA panel), including EGFR/MET/KRAS/PI3K/PTEN mutations and EGFR/MET/KRAS amplifications. Hypothesizing a prevalence of candidate alterations of 30% and 0% in resistant and sensitive HER2-positive patients, respectively, 20 patients per group were needed.Results: AMNESIA panel alterations were significantly more frequent in resistant (11 of 20, 55%) as compared with sensitive (0% of 17) patients (P < 0.001), and in HER2 IHC 2⁺ (7 of 13, 53.8%) than 3⁺ (4 of 24, 16.7%) tumors (P = 0.028). Patients with tumors bearing no candidate alterations had a significantly longer median progression-free [5.2 vs. 2.6 months; HR, 0.34; 95% confidence interval (CI), 0.07-0.48; P = 0.001] and overall survival (16.1 vs. 7.6 months; HR, 0.38; 95% CI, 0.09-0.75; P = 0.015). The predictive accuracy of the AMNESIA panel and HER2 IHC was 76% and 65%, respectively. The predictive accuracy of the combined evaluation of the AMNESIA panel and HER2 IHC was 84%.Conclusions: Our panel of candidate genomic alterations may be clinically useful to predict primary resistance to trastuzumab in patients with HER2-positive metastatic gastric cancer and should be further validated with the aim of molecularly stratifying HER2-addicted cancers for the development of novel treatment strategies. Clin Cancer Res; 24(5); 1082-9. ©2017 AACR.

Genomic Heterogeneity as a Barrier to Precision Medicine in Gastroesophageal Adenocarcinoma

Gastroesophageal adenocarcinoma (GEA) is a lethal disease where targeted therapies, even when guided by genomic biomarkers, have had limited efficacy. A potential reason for the failure of such therapies is that genomic profiling results could commonly differ between the primary and metastatic tumors. To evaluate genomic heterogeneity, we sequenced paired primary GEA and synchronous metastatic lesions across multiple cohorts, finding extensive differences in genomic alterations, including discrepancies in potentially clinically relevant alterations. Multiregion sequencing showed significant discrepancy within the primary tumor (PT) and between the PT and disseminated disease, with oncogene amplification profiles commonly discordant. In addition, a pilot analysis of cell-free DNA (cfDNA) sequencing demonstrated the feasibility of detecting genomic amplifications not detected in PT sampling. Lastly, we profiled paired primary tumors, metastatic tumors, and cfDNA from patients enrolled in the personalized antibodies for GEA (PANGEA) trial of targeted therapies in GEA and found that genomic biomarkers were recurrently discrepant between the PT and untreated metastases. Divergent primary and metastatic tissue profiling led to treatment reassignment in 32% (9/28) of patients. In discordant primary and metastatic lesions, we found 87.5% concordance for targetable alterations in metastatic tissue and cfDNA, suggesting the potential for cfDNA profiling to enhance selection of therapy.Significance: We demonstrate frequent baseline heterogeneity in targetable genomic alterations in GEA, indicating that current tissue sampling practices for biomarker testing do not effectively guide precision medicine in this disease and that routine profiling of metastatic lesions and/or cfDNA should be systematically evaluated. Cancer Discov; 8(1); 37-48. ©2017 AACR.See related commentary by Sundar and Tan, p. 14See related article by Janjigian et al., p. 49This article is highlighted in the In This Issue feature, p. 1.