Global Ring Study to Investigate the Comparability of Total Assay Performance of Commercial Claudin 18 Antibodies for Evaluation in Gastric Cancer.

Claudin 18.2 (CLDN18.2), the dominant isoform of CLDN18 in gastric tissues, is a highly specific tight junction protein of the gastric mucosa with variably retained expressions in gastric and gastroesophageal junction cancers. Additionally, CLDN18.2-targeted treatment with zolbetuximab, in combination with chemotherapy, has recently been assessed in 2 phase-III studies of patients with HER2-negative, locally advanced, unresectable, or metastatic gastric or gastroesophageal junction adenocarcinoma. These trials used the investigational VENTANA CLDN18 (43-14A) RxDx immunohistochemistry (IHC) assay on the Ventana BenchMark platform to identify patients eligible for CLDN18.2-targeted treatment. We report the findings of a global ring study evaluating the analytical comparability of concordance of the results of 3 CLDN18 antibodies (Ventana, LSBio, and Novus) stained on 3 IHC-staining platforms (Ventana, Dako, and Leica). A tissue microarray (TMA), comprising 15 gastric cancer cases, was stained by 27 laboratories across 11 countries. Each laboratory stained the TMAs using at least 2 of the 3 evaluated CLDN18 antibodies. Stained TMAs were assessed and scored using an agreed IHC-scoring algorithm, and the results were collated for statistical analysis. The data confirmed a high level of concordance for the VENTANA CLDN18 (43-14A; Ventana platform only) and LSBio antibodies on both the Dako and Leica platforms, with accuracy, precision, sensitivity, and specificity rates all reaching a minimum acceptable ≥85% threshold and good-to-excellent levels of concordance as measured by Cohen's kappa coefficient. The Novus antibody showed the highest level of variability against the reference central laboratory results for the same antibody/platform combinations. It also failed to meet the threshold for accuracy and sensitivity when used on either the Dako or Leica platform. These results demonstrated the reliability of IHC testing for CLDN18 expression in gastric tumor samples when using commercially available platforms with an appropriate methodology and primary antibody selection.

Population Based Time Trends in the Epidemiology and Mortality of Gastroesophageal Junction and Esophageal Adenocarcinoma.

BACKGROUND: Limited data are available on the epidemiology of gastroesophageal junction adenocarcinoma (GEJAC), particularly in comparison to esophageal adenocarcinoma (EAC). With the advent of molecular non-endoscopic Barrett's esophagus (BE) detection tests which sample the esophagus and gastroesophageal junction, early detection of EAC and GEJAC has become a possibility and their epidemiology has gained importance. AIMS: We sought to evaluate time trends in the epidemiology and survival of patients with EAC and GEJAC in a population-based cohort. METHODS: EAC and GEJAC patients from 1976 to 2019 were identified using ICD 9 and 10 diagnostic codes from the Rochester Epidemiology Project (REP). Clinical data and survival status were abstracted. Poisson regression was used to calculate incidence rate ratios (IRR). Survival analysis and Cox proportional models were used to assess predictors of survival. RESULTS: We included 443 patients (287 EAC,156 GEJAC). The incidence of EAC and GEJAC during 1976-2019 was 1.40 (CI 1.1-1.74) and 0.83 (CI 0.61-1.11) per 100,000 people, respectively. There was an increase in the incidence of EAC (IRR = 2.45, p = 0.011) and GEJAC (IRR = 3.17, p = 0.08) from 2000 to 2004 compared to 1995-1999, plateauing in later time periods. Most patients had associated BE and presented at advanced stages, leading to high 5-year mortality rates (66% in EAC and 59% in GEJAC). Age and stage at diagnosis were predictors of mortality. CONCLUSION: The rising incidence of EAC/GEJAC appears to have plateaued somewhat in the last decade. However, both cancers present at advanced stages with persistently poor survival, underscoring the need for early detection.

High Interobserver Variability Among Pathologists Using Combined Positive Score to Evaluate PD-L1 Expression in Gastric, Gastroesophageal Junction, and Esophageal Adenocarcinoma.

Reliable, reproducible methods to interpret programmed death ligand-1 (PD-L1) expression on tumor cells (TC) and immune cells (IC) are needed for pathologists to inform decisions associated with checkpoint inhibitor therapies. Our international study compared interpathologist agreement of PD-L1 expression using the combined positive score (CPS) under standardized conditions on samples from patients with gastric/gastroesophageal junction/esophageal adenocarcinoma. Tissue sections from 100 adenocarcinoma pretreatment biopsies were stained in a single laboratory using the PD-L1 immunohistochemistry 28-8 and 22C3 (Agilent) pharmDx immunohistochemical assays. PD-L1 CPS was evaluated by 12 pathologists on scanned whole slide images of these biopsies before and after a 2-hour CPS training session by Agilent. Additionally, pathologists determined PD-L1-positive TC, IC, and total viable TC on a single tissue fragment from 35 of 100 biopsy samples. Scoring agreement among pathologists was assessed using the intraclass correlation coefficient (ICC). Interobserver variability for CPS for 100 biopsies was high, with only fair agreement among pathologists both pre- (range, 0.45-0.55) and posttraining (range, 0.56-0.57) for both assays. For the 35 single biopsy samples, poor/fair agreement was also observed for the total number of viable TC (ICC, 0.09), number of PD-L1-positive IC (ICC, 0.19), number of PD-L1-positive TC (ICC, 0.54), and calculated CPS (ICC, 0.14), whereas calculated TC score (positive TC/total TC) showed excellent agreement (ICC, 0.82). Retrospective histologic review of samples with the poorest interpathologist agreement revealed the following as possible confounding factors: (1) ambiguous identification of positively staining stromal cells, (2) faint or variable intensity of staining, (3) difficulty in distinguishing membranous from cytoplasmic tumor staining, and (4) cautery and crush artifacts. These results emphasize the need for objective techniques to standardize the interpretation of PD-L1 expression when using the CPS methodology on gastric/gastroesophageal junction cancer biopsies to accurately identify patients most likely to benefit from immune checkpoint inhibitor therapy.

Concordance of microsatellite instability and mismatch repair status in paired biopsies and surgical specimens of resectable gastroesophageal adenocarcinoma: time for a call to action.

BACKGROUND: Reliability of mismatch repair proteins and microsatellite instability assessment is essential in order to define treatment strategy and identify candidates to immune checkpoint inhibitors in locally advanced gastroesophageal carcinoma. We evaluated the concordance of deficient mismatch repair (dMMR) and microsatellite instability-high (MSI-H) status between endoscopic biopsies and surgical specimens. METHODS: Consecutive patients with resectable gastric or gastroesophageal junction adenocarcinoma classified as MSI-H/dMMR by polymerase chain reaction (PCR) or immunohistochemistry (IHC) and operated at three referral Institutions were included. The primary endpoint was the rate of concordance between biopsy and surgical samples. If needed, central revision by IHC/PCR was performed by specialized pathologists from coordinating Institutions. RESULTS: Thirteen (19.7%) out of 66 patients showed discordant MSI-H/dMMR results in the original pathology reports. In most cases (11, 16.7%) this was due to the diagnosis of proficient mismatch repair status on biopsies. Among the ten cases available for central review, four were due to sample issues, four were reclassified as dMMR, one case showed dMMR status but was classified as microsatellite stable by PCR, one was linked to misdiagnosis of endoscopic biopsy by the local pathologist. Heterogeneity of mismatch repair proteins staining was observed in two cases. CONCLUSIONS: Available methods can lead to conflicting results in MSI-H/dMMR evaluation between endoscopic biopsies and surgical samples of gastroesophageal adenocarcinoma. Strategies aiming to improve the reliability of assessment should be primarily focused on the optimization of tissue collection and management during endoscopy and adequate training of dedicated gastrointestinal pathologists within the multidisciplinary team.

Efficacy of PD-1 Inhibitors in First-Line Treatment for Advanced Gastroesophageal Junction and Gastric Cancer by Subgroups: A Systematic Review and Meta-Analysis.

BACKGROUND: PD-1 inhibitors have been approved for the first-line treatment of patients with advanced gastric cancer, gastroesophageal junction cancer, or esophageal adenocarcinoma. However, the results of several clinical trials are not entirely consistent, and the dominant population of first-line immunotherapy for advanced gastric/gastroesophageal junction cancer still needs to be precisely determined. OBJECTIVE: This objective of this study is to evaluate the efficacy of anti-PD-1/PD-L1 therapy in advanced gastric/gastroesophageal junction adenocarcinoma patients through a systematic review and meta-analysis of relevant clinical trials. METHOD: The PubMed, Embase, and Cochrane Library electronic databases were searched up to August 1, 2022, for clinical trials of anti-PD-1/PD-L1 immunotherapy for the first-line treatment of advanced gastroesophageal cancer. Hazard ratios and 95% confidence intervals for overall survival, progression-free survival, and objective response rates were extracted and pooled for meta-analysis. Prespecified subgroups included the following: agent type, PD-L1 expression, and high microsatellite instability. RESULTS: This study analyzed 5 RCTs involving 3,355 patients. Compared with the chemotherapy group, the combined immunotherapy group had a significantly higher objective response rate (OR = 0.63, 95% CI: 0.55-0.72, p < 0.00001) and prolonged overall survival (HR = 0.82, 95% CI: 0.76-0.88, p < 0.00001) and progression-free survival (HR = 0.75, 95% CI: 0.69-0.82, p < 0.00001). The combination of immunotherapy and chemotherapy prolonged OS in both MSI-H (HR = 0.38, p = 0.002) and MSS (HR = 0.78, p < 0.00001) populations, but there was a significant difference between groups (p = 0.02). However, in improving ORR, the benefit of ICI combined with chemotherapy in the MSS group and MSI-H group was not significantly different between groups (p = 0.52). Combination therapy with ICIs was more effective than chemotherapy alone in prolonging OS in the subgroup with a high CPS, regardless of the CPS cutoff for PD-L1. However, when the cutoff of CPS was 1, the difference between subgroups did not reach statistical significance (p = 0.12), while the benefit ratio of the MSI-H group was higher when the cutoff was 10 (p = 0.004) than when the cutoff value was 5 (p = 0.002). CONCLUSIONS: For first-line treatment of advanced gastroesophageal cancer, an ICI combination strategy is more effective than chemotherapy. The subgroup of patients with a CPS ≥10 has a more significant benefit, and CPS ≥10 has the potential to be used as an accurate marker of the dominant population of immuno-combined therapy.

A study protocol of a randomized phase II trial of perioperative chemoimmunotherapy verses perioperative chemoimmunotherapy plus preoperative chemoradiation for locally advanced gastric (G) or gastroesophageal junction (GEJ) adenocarcinoma: the NeoRacing study.

BACKGROUND: Perioperative chemotherapy (ChT) and preoperative chemoradiation (CRT) are both the standard treatments for locally advanced gastric cancer (LAGC). CRT can achieve a higher pathological complete regression (pCR) rate, but whether this higher pCR rate can be transformed into a long-term survival benefit remains inconclusive. Therefore, relevant studies are in progress. On the other hand, immunotherapy has been established for the first-line treatment of advanced gastric cancer (AGC) and has been widely explored in the perioperative setting. The combination of chemotherapy/radiotherapy and immunotherapy may have a synergistic effect, which will lead to a better antitumor effect. The preliminary reports of ongoing studies show promising results, including a further improved pCR rate. However, the preferred treatment combination for LAGC is still not established. To solve this problem, we are carrying out this randomized phase II trial, which aims to evaluate the efficacy and safety of perioperative chemotherapy plus the use of PD-1 antibody with or without preoperative chemoradiation for LAGC. METHODS: Eligible patients with LAGC or gastroesophageal junction (GEJ) adenocarcinoma were randomized to receive perioperative ChT, PD-1 antibody, surgery with (Arm A) or without preoperative CRT (Arm B), and PD-1 antibody maintenance until one year after surgery. The primary endpoint of this study is that the pCR rate of Arm A will be significantly higher than that of Arm B. The secondary endpoints include the pathological partial regression (pPR) rate, R0 resection rate, objective response rate (ORR), event-free survival (EFS), overall survival (OS), safety and surgical complications. Moreover, several explorative endpoints will be evaluated to find and validate the predictive biomarkers of immunotherapy. DISCUSSION: The results of the NeoRacing study will provide important information concerning the application of PD-1 antibody in LAGC patients during the perioperative setting. Meanwhile, the two treatment protocols will be compared in terms of efficacy and safety. TRIAL REGISTRATION: ClinicalTrials.gov , NCT05161572 . Registered 17 December 2021 - Retrospectively registered.

Nodal downstaging to ypN0 after neoadjuvant chemotherapy positively impacts on survival of cT4N+ GC/GEJ patients.

BACKGROUND: The prognostic value of histomorphologic regression in primary gastric and gastroesophageal cancers (GC/GEJ) has been previously established, however, the impact of lymph node (LN) regression on survival still remains unclear. METHODS: A prospectively maintained database was reviewed to identify cT4N+ gastric and gastroesophageal cancers (GC/GEJ) after NAC (neoadjuvant chemotherapy). Patients were categorized into two groups based on LN status: cN+/ypN0 (downstaged N0) and cN+/ypN+ (persistent N+), long-term survival were analyzed using Kaplan-Meier survival estimates. RESULTS: In total, 125 patients with cT4N+ GC/GEJ underwent NAC followed by surgery were enrolled. A total of 39 patients (31.2%) had cN+/ypN0 (ypN0) disease, 86 patients (68.8%) had cN+/ypN+ (ypN+) disease. Prognosis in ypN+ patients was significantly worse than those in ypN0 group for 3- and 5-year overall survival (OS) (p < 0.05). The 3-year OS was 83%, 44% in ypN0 and ypN+ group, respectively. The 5-year OS was 75%, 35% in ypN0 and ypN+ group, respectively. Multivariable analysis suggested that multivisceral resection (hazard ratio [HR] = 0.33, 95% confidence interval [CI]: 0.14-0.76, p = 0.009), and ypN+ (HR = 3.42, 95% CI: 1.15-10.13, p =0.027) were independent prognostic factors for OS. CONCLUSION: Nodal downstaging is an important hallmark representing the effectiveness of NAC for GC/GEJ, and it positively impacts on survival of these patients.

Epidemiological Review of Gastroesophageal Junction Adenocarcinoma in Asian Countries.

BACKGROUND: Similar trends in the prevalence of gastroesophageal reflux disease (GERD), obesity, and Helicobacter pylori infection have been observed in Asian and Western countries despite their time differences. However, it is unclear whether the prevalence of gastroesophageal junction adenocarcinomas in Asian countries is increasing. In this review, we discuss the epidemiological trends of gastroesophageal junction adenocarcinoma in Asian countries. SUMMARY: The prevalence of GERD is increasing in Asian countries, but most cases are considered mild. Obesity is a serious problem worldwide, but it is considered less serious in Asia than in Western countries. In Asian countries where gastric cancer is common, both cardiac and noncardiac cancers are associated with high rates of H. pylori infection, which is considered a carcinogenic risk factor for both sites of cancer. The widespread use of H. pylori eradication therapy for chronic gastritis in several Asian countries has not directly led to an increased prevalence of esophageal adenocarcinoma. One of the originating sites of junctional adenocarcinoma in most Asian countries is Barrett's esophagus, with short-segment Barrett's esophagus having much lower carcinogenicity than long-segment Barrett's esophagus. Key Messages: Considering the future trends of several risk factors for gastroesophageal junction adenocarcinoma in Asian countries, it is likely that the incidence of gastroesophageal junction adenocarcinoma will gradually increase, but not at a rate that exceeds that of squamous cell carcinoma, as in Western countries.

Tumor Response and Symptom Palliation from RAINBOW, a Phase III Trial of Ramucirumab Plus Paclitaxel in Previously Treated Advanced Gastric Cancer.

BACKGROUND: In the intent-to-treat (ITT) population of the RAINBOW study, objective response rate (ORR) was 28% and 16% in the ramucirumab and control arms, respectively. To further characterize tumor response, we present details on timing and extent of tumor shrinkage, as well as associations with symptom palliation. MATERIALS AND METHODS: Tumor response was assessed with RECIST v1.1, and quality of life (QoL) was assessed with the European Organization for Research and Treatment of Cancer Quality-of-Life Questionnaire-Core 30 (EORTC QLQ-C30) v3.0. Prespecified and post hoc analyses were conducted in the ITT population, patients with measurable disease, or responders, and included best overall response (BOR), ORR, disease control rate (DCR), duration of response, time to response (TtR), change in tumor size, and associations of QoL with tumor shrinkage and BOR. RESULTS: In both treatment arms, median TtR was 1.5 months. Responses were more durable in the ramucirumab versus control arm (median 4.4 vs. 2.8 months). In patients with measurable disease (78% of ITT), ORR was 36% versus 20%; DCR was 81% versus 61% in the ramucirumab versus control arms. Waterfall plots demonstrated more tumor shrinkage in the ramucirumab versus control arm. Regardless of treatment, tumor response and stable disease were associated with improved or stable QoL, with more tumor shrinkage associated with greater symptom palliation. CONCLUSION: Treatment with ramucirumab plus paclitaxel yielded the highest ORR reported to date for patients with previously treated advanced gastric or gastroesophageal junction adenocarcinoma. Additional details demonstrate robustness of tumor response results. The extent of tumor shrinkage is directly associated with symptom palliation and should be considered when evaluating patient needs and treatment selection. Clinical trial identification number. NCT01170663. IMPLICATIONS FOR PRACTICE: Ramucirumab plus paclitaxel is a recognized standard of care as it improves survival for patients with advanced gastric or gastroesophageal junction adenocarcinoma who have been previously treated with recommended first-line therapy. These additional data on tumor response demonstrate a positive association between tumor shrinkage and symptom palliation in a patient population that is often symptomatic. These observations included patients with nonmeasurable disease, a group of patients often underrepresented in clinical trials. This knowledge can inform treatment decisions, which align individual patient characteristics and needs with demonstrated benefits.

Early Weight Loss as a Prognostic Factor in Patients with Advanced Gastric Cancer: Analyses from REGARD, RAINBOW, and RAINFALL Phase III Studies.

BACKGROUND: Weight loss is common in advanced gastric and gastroesophageal junction adenocarcinoma (G/GEA); however, the prognostic implications of weight loss during the first cycle (C1) of chemotherapy remain poorly characterized. In this study, we investigated the impact of early weight loss during systemic treatment as a potential prognostic factor for overall survival (OS) in patients with advanced G/GEA. MATERIALS AND METHODS: We performed a post hoc analysis of three phase III studies of ramucirumab. Patients were categorized into two groups: weight loss of ≥3% and <3% based on weight change during C1 (3-4 weeks) of treatment. OS by weight groups was assessed for each study and as a pooled meta-analysis. The effect of C1 weight change on patient survival was evaluated using univariate and multivariate Cox models. RESULTS: A total of 1,464 patients with weight data at the end of C1 were analyzed: REGARD (n = 311), RAINBOW (n = 591), and RAINFALL (n = 562). For all three studies, there were fewer patients in the weight loss ≥3% than <3% group. OS was numerically shorter for patients with weight loss of ≥3% than for patients with weight loss of <3% during C1 irrespective of treatment arm. Similar treatment independent effects of early weight loss on OS were observed in the meta-analysis. Overall, early weight loss ≥3% was associated with shorter survival in patients receiving active drug as well as placebo/best supportive care. CONCLUSION: This large post hoc analysis demonstrated that weight loss of ≥3% during C1 was a negative prognostic factor for OS in patients with advanced G/GEA. IMPLICATIONS FOR PRACTICE: This comprehensive analysis examining early weight loss during systemic treatment as a predictor of survival outcomes in patients with advanced gastric and gastroesophageal junction adenocarcinoma (G/GEA) includes a large sample size, reliable on-treatment data reported in well-conducted phase III clinical trials, and global representation of cancer patients with advanced G/GEA. Understanding the impact of on-treatment weight loss is clinically relevant and may represent an opportunity for targeted interventions.

FAST: a randomised phase II study of zolbetuximab (IMAB362) plus EOX versus EOX alone for first-line treatment of advanced CLDN18.2-positive gastric and gastro-oesophageal adenocarcinoma.

BACKGROUND: Claudin 18.2 (CLDN18.2) is contained within normal gastric mucosa epithelial tight junctions; upon malignant transformation, CLDN18.2 epitopes become exposed. Zolbetuximab, a chimeric monoclonal antibody, mediates specific killing of CLDN18.2-positive cells through immune effector mechanisms. PATIENTS AND METHODS: The FAST study enrolled advanced gastric/gastro-oesophageal junction and oesophageal adenocarcinoma patients (aged ≥18 years) with moderate-to-strong CLDN18.2 expression in ≥40% tumour cells. Patients received first-line epirubicin + oxaliplatin + capecitabine (EOX, arm 1, n = 84) every 3 weeks (Q3W), or zolbetuximab + EOX (loading dose, 800 mg/m2 then 600 mg/m2 Q3W) (arm 2, n = 77). Arm 3 (exploratory) was added after enrolment initiation (zolbetuximab + EOX 1000 mg/m2 Q3W, n = 85). The primary endpoint was progression-free survival (PFS) and overall survival (OS) was a secondary endpoint. RESULTS: In the overall population, both PFS [hazard ratio (HR) = 0.44; 95% confidence interval (CI), 0.29-0.67; P < 0.0005] and OS (HR = 0.55; 95% CI, 0.39-0.77; P < 0.0005) were significantly improved with zolbetuximab + EOX (arm 2) compared with EOX alone (arm 1). This significant PFS benefit was retained in patients with moderate-to-strong CLDN18.2 expression in ≥70% of tumour cells (HR = 0.38; 95% CI, 0.23-0.62; P < 0.0005). Significant improvement in PFS was also reported in the overall population of arm 3 versus arm 1 (HR = 0.58; 95% CI, 0.39-0.85; P = 0.0114) but not in high CLDN18.2-expressing patients; no significant improvement in OS was observed in either population. Most adverse events (AEs) related to zolbetuximab + EOX (nausea, vomiting, neutropenia, anaemia) were grade 1-2. Grade ≥3 AEs showed no substantial increases overall (zolbetuximab + EOX versus EOX alone). CONCLUSIONS: In advanced gastric/gastro-oesophageal junction and oesophageal adenocarcinoma patients expressing CLDN18.2, adding zolbetuximab to first-line EOX provided longer PFS and OS versus EOX alone. Zolbetuximab + EOX was generally tolerated and AEs were manageable. Zolbetuximab 800/600 mg/m2 is being evaluated in phase III studies based on clinical benefit observed in the overall population and in patients with moderate-to-strong CLDN18.2 expression in ≥70% of tumour cells.

Prognostic importance of molecular-like classification in gastroesophageal junction tumors (Izmir Oncology Group [IZOG] study).

A comprehensive molecular classification was published in 2014 within The Cancer Genome Atlas (TCGA) to guide clinical approaches and treatment strategies. This study aimed to investigate the clinicopathological and prognostic importance of the classification using immunohistochemistry (IHC) and chromogenic in situ hybridization (CISH) to identify potential surrogate markers of molecular changes in gastroesophageal junction (GEJ) adenocarcinomas. A total of 52 GEJ adenocarcinomas were divided into five groups using IHC with MLH-1, E-cadherin, p53 and CISH with EBER: 1) microsatellite unstable (MSI: negative with MLH-1), 2) genomically stable tumors (GS: positive with p53), 3) chromosomally unstable tumors (CUN: negative with e-cadherin), 4) EBV+ tumors (EBV+: positive with EBER) and 5) unclassifiable (G-NOS: MLH-1 and e-cadherin positive with p53 and negative with EBER). The largest group consisted of 24 (46.2%) cases of CUN tumors. This group was followed by groups of GS with 14 (26.9%) cases, MSI with 7 (13.5%) cases, and EBV + with 3 (5.8%) cases, respectively. Although this classification was not associated with pathological features, it was found to be closely related to prognosis (p = 0.029). Patients with EBV+ tumors had the longest overall survival, followed by the G-NOS, MSI, CUN, GS groups.

Safety and efficacy of sintilimab combined with oxaliplatin/capecitabine as first-line treatment in patients with locally advanced or metastatic gastric/gastroesophageal junction adenocarcinoma in a phase Ib clinical trial.

BACKGROUND: Sintilimab blocks the interaction between programmed death-1 (PD-1) and its ligands. The safety and efficacy of sintilimab combined with oxaliplatin/capecitabine (CapeOx) as first-line treatment were evaluated in patients with gastric (G)/gastroesophageal junction (GEJ) adenocarcinoma in a phase Ib clinical trial. METHODS: Patients with locally advanced or metastatic G/GEJ adenocarcinoma without previous systemic treatment were enrolled as one cohort of a multi-cohort study. Sintilimab was administered at a dose of 200 mg intravenously (IV) in combination with CapeOx (1000 mg/m2 capecitabine orally, bid, D1-14 and 130 mg/m2 oxaliplatin IV, D1) every 21 days for up to 6 cycles. After combination treatment, patients continued to receive sintilimab (200 mg) at 3 weekly intervals as maintenance therapy until progressive disease (PD), unacceptable toxicity, withdrawal of informed consent, or for up to 24 months. Adverse events (AEs) were monitored to assess safety in terms of their frequency, intensity and causality. The efficacy endpoints included the objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS) and overall survival (OS). Tumor mutation burden (TMB) was evaluated for its association with clinical response. RESULTS: A total of 20 patients were enrolled and received sintilimab plus CapeOx. All patients reported treatment-related AEs (TRAEs). Grade 3-4 TRAEs were found in 11 (55.0%) patients. Seventeen patients obtained partial response and the ORR was 85.0% (95% CI: 62.1-96.8%). Three (15.0%) had stable disease and DCR was 100.0% (95% CI: 83.2-100.0%). As data cutoff of May 1, 2019, the median follow-up was 7.8 months. The median PFS was 7.5 months (95% CI: 6.2-9.4) and median OS had not been reached. The OS rates at 6 months and 12 months were 100.0 and 68.0%. No association was observed between TMB and efficacy. CONCLUSIONS: Sintilimab combined with CapeOx as first-line treatment demonstrated acceptable safety and promising efficacy. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02937116 . Registered 8 October 2016.

Brain metastases in patients with upper gastrointestinal cancer is associated with proximally located adenocarcinoma and lymph node metastases.

BACKGROUND: As cancer patients are surviving longer, more patients manifest brain metastases (BRMs). However, the rate of BRMs from upper gastrointestinal cancer is unclear. We therefore evaluated the frequency and prognostic effect of BRMs in this setting. METHODS: We analyzed records of 2348 patients who were treated between January 2002 and December 2016 for upper gastrointestinal cancer, including esophageal and gastroesophageal junction adenocarcinoma (EAC; proximal EAC, Siewert types I and II), esophageal squamous cell carcinoma (ESCC), and gastric adenocarcinoma (GAC; Siewert type III and stomach cancer) in our Gastrointestinal Medical Oncology Database. Frequency, risk factors, and survival after BRMs were evaluated. RESULTS: Of 2348 patients, 68 (2.9%) had BRMs upon follow-up. The BRM rates were as follows: proximal EAC, 4.8%; Siewert type I, 5.9%; Siewert type II, 2.2%; Siewert type III, 0.7%; ESCC: 1.2%; and stomach cancer, 0%. Among EAC patients, Siewert type I and lymph node metastases were independent the risk factors for BRMs in the multivariable analysis. The median overall survival (OS) in the 68 patients with BRMs was only 1.16 years (95% CI 0.78-1.61). However, OS for patients who had a solitary BRM, who had BRM but no other distant metastasis, or who underwent surgery or stereotactic radiosurgery favorable. CONCLUSION: Patients with proximally located adenocarcinoma, or with lymph node metastases are at a higher risk for BRMs and patients fare better after treatment of isolated BRM.

True esophagogastric junction adenocarcinoma: background of its definition and current surgical trends.

The definition of true esophagogastric junction (EGJ) adenocarcinoma and its surgical treatment are debatable. We review the basis for the current definition and the Japanese surgical strategy in managing true EGJ adenocarcinoma. The Siewert classification is a well-known anatomical classification system for EGJ adenocarcinomas: type II tumors in the region 1 cm above and 2 cm below the EGJ are described as "true carcinoma of the cardia". Coincidentally, this range matches gastric cardiac gland distribution. Conversely, Nishi's classification is generally used to describe EGJ carcinomas, defined as tumors with the center located within 2 cm above and 2 cm below the EGJ, regardless of their histological subtype. This range coincides with the extent of the lower esophageal sphincter combined with gastric cardiac gland distribution. The current Japanese surgical strategy focuses on the tumor range from the EGJ to the esophagus and stomach. According to previous studies, the strategy can be roughly classified into three types. The optimal surgical procedure for true EGJ adenocarcinoma is controversial. However, an ongoing Japanese nationwide prospective trial will help confirm the appropriate standard surgery, including the optimal extent of lymph node dissection.

FGFR2-Altered Gastroesophageal Adenocarcinomas Are an Uncommon Clinicopathologic Entity with a Distinct Genomic Landscape.

BACKGROUND: With the exception of trastuzumab, therapies directed at receptor tyrosine kinases (RTKs) in gastroesophageal adenocarcinomas (GEA) have had limited success. Recurrent fibroblast growth factor receptor 2 (FGFR2) alterations exist in GEA; however, little is known about the genomic landscape of FGFR2-altered GEA. We examined FGFR2 alteration frequency and frequency of co-occurring alterations in GEA. SUBJECTS, MATERIALS, AND METHODS: A total of 6,667 tissue specimens from patients with advanced GEA were assayed using hybrid capture-based genomic profiling. Tumor mutational burden (TMB) was determined on up to 1.1 Mb of sequenced DNA, and microsatellite instability was determined on 95 or 114 loci. Descriptive statistics were used to compare subgroups. RESULTS: We identified a total of 269 (4.0%) FGFR2-altered cases consisting of FGFR2-amplified (amp; 193, 72% of FGFR2-altered), FGFR2-mutated (36, 13%), FGFR2-rearranged (re; 23, 8.6%), and cases with multiple FGFR2 alterations (17, 6.3%). Co-occurring alterations in other GEA RTK targets including ERBB2 (10%), EGFR (8%), and MET (3%) were observed across all classes of FGFR2-altered GEA. Co-occurring alterations in MYC (17%), KRAS (10%), and PIK3CA (5.6%) were also observed frequently. Cases with FGFR2amp and FGFR2re were exclusively microsatellite stable. The median TMB for FGFR2-altered GEA was 3.6 mut/mb, not significantly different from a median of 4.3 mut/mb seen in FGFR2 wild-type samples. CONCLUSION: FGFR2-altered GEA is a heterogenous subgroup with approximately 20% of FGFR2-altered samples harboring concurrent RTK alterations. Putative co-occurring modifiers of FGFR2-directed therapy including oncogenic MYC, KRAS, and PIK3CA alterations were also frequent, suggesting that pretreatment molecular analyses may be needed to facilitate rational combination therapies and optimize patient selection for clinical trials. IMPLICATIONS FOR PRACTICE: Actionable receptor tyrosine kinase alterations assayed within a genomic context with therapeutic implications remain limited to HER2 amplification in gastroesophageal adenocarcinomas (GEA). Composite biomarkers and heterogeneity assessment are critical in optimizing patients selected for targeted therapies in GEA. Comprehensive genomic profiling in FGFR2-altered GEA parallels the heterogeneity findings in HER2-amplified GEA and adds support to the utility of genomic profiling in advanced gastroesophageal adenocarcinomas.

Combined taxane-based chemotherapy and intensity-modulated radiotherapy with simultaneous integrated boost for gastroesophageal junction adenocarcinoma.

We describe our experience, gained over the past 3 years, in the treatment of gastroesophageal junction adenocarcinoma, whose incidence has been increasing in recent years. In our series, we present the results to a follow-up of about 2 years for a total of 18 patients, treated with a particularly intensive combination treatment. It consists of neoadjuvant induction chemotherapy with the protocol docetaxel-cisplatin-5-fluorouracil for four cycles, before a concomitant chemoradiotherapy treatment. During combined phase, patients received an intensity-modulated radiotherapy and a weekly cisplatin. We will present the data to a long follow-up time and we will discuss the literature, the integration with thoracoabdominal surgery and other specific issues of this pathology.

Perioperative chemotherapy versus neoadjuvant chemoradiotherapy for esophageal or GEJ adenocarcinoma: A propensity score-matched analysis comparing toxicity, pathologic outcome, and survival.

OBJECTIVES: To evaluate toxicity, pathologic outcome, and survival after perioperative chemotherapy (pCT) compared to neoadjuvant chemoradiotherapy (nCRT) followed by surgery for patients with resectable esophageal or gastroesophageal junction (GEJ) adenocarcinoma. METHODS: Consecutive patients with resectable esophageal or GEJ adenocarcinoma who underwent pCT (epirubicin, cisplatin, and capecitabine) or nCRT (paclitaxel, carboplatin, and 41.4 Gy) followed by surgery in a tertiary referral center in the Netherlands were compared. Propensity score matching was applied to create comparable groups. RESULTS: Of 193 eligible patients, 21 were discarded after propensity score matching; 86 and 86 patients who underwent pCT and nCRT, respectively, remained. Grade ≥3 thromboembolic events occurred only in the pCT group (19% vs. 0%, P < 0.001), whereas grade ≥3 leukopenia occurred more frequently in the nCRT group (14% vs. 4%, P = 0.015). No significant differences regarding postoperative morbidity and mortality were found. Pathologic complete response was more frequently observed with nCRT (18% vs. 11%, P < 0.001), without significantly improving radicality rates (95% vs. 89%, P = 0.149). Both strategies resulted in comparable 3-year progression-free survival (pCT vs. nCRT: 46% vs. 55%, P = 0.344) and overall survival rates (49% vs. 50%, P = 0.934). At 3-year follow-up, fewer locoregional disease progression occurred in the nCRT group (19% vs. 37%, P = 0.024). CONCLUSIONS: Compared to perioperative chemotherapy, neoadjuvant chemoradiotherapy achieves higher pathologic response rates and a lower risk of locoregional disease progression, without improving survival.

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.

Western strategy for EGJ carcinoma.

In this paper, the epidemiological and clinicobiological behavior of esophagogastric junction (EGJ) adenocarcinoma in the West is compared and contrasted to that in the East, and an overview is provided of current therapeutic strategies employed for this type of tumor in Western countries. It is well known that multimodal treatment is the therapeutic standard in locally advanced EGJ adenocarcinoma, but whether neoadjuvant/perioperative chemotherapy (CT) or neoadjuvant chemoradiotherapy (CRT) is the optimal approach is still debated. Neoadjuvant CRT improves local control in locally advanced Siewert type I and II tumors, so it should be considered the treatment of choice. In the subset of these patients with microscopic systemic disease at diagnosis, more intensive exclusive chemotherapy protocols could be of benefit. Therefore, there is an urgent need to identify these patients before planning the treatment. For Siewert type III tumors, perioperative chemotherapy is the standard. While there is general agreement on the optimal surgical approach for Siewert types I and III (a two-field Ivor Lewis operation and a total gastrectomy with distal esophagectomy, respectively), no standard surgical treatment has been defined for Siewert type II tumors. When data from Western series on proximal and circumferential resection margins and on nodal spread in Siewert type II tumors are taken into account, the optimal surgical approach appears to be Ivor Lewis esophagectomy. Whether the extent of esophageal invasion can correctly predict nodal involvement in middle-upper mediastinal stations as a means to restrict indications for transthoracic esophagectomy requires further investigation in the West.