Some pertinent studies have demonstrated that Epstein–Barr virus-associated gastric cancer (EBVaGC) patients showed a favorable clinical outcome to immunotherapy and Epstein–Barr virus (EBV)-positive status might be a potential biomarker for immunotherapy in gastric cancer (GC). However, knowledge of given exposure to EBVaGC to the first-line immunotherapy is largely inadequate. Moreover, whether camrelizumab can be as effective as other PD-1 inhibitors in the treatment of advanced EBVaGC has not been reported. We report a case of advanced EBVaGC patient with a positive expression of PD-L1, enriched PD-L1+CD68+macrophages, and high TMB who had a long-term partial response and manageable toxicity to the combined approach of camrelizumab (a novel PD-1 inhibitor) and oxaliplatin plus oral S-1 (SOX). As the first-line treatment of advanced EBVaGC patients, camrelizumab combined with SOX regimen may provide a novel combined approach with favorable response and manageable safety. Combination of multiple biomarkers could have a higher effective predictive capacity to immunotherapy. Integrated treatment (chemo-immunotherapy and radiotherapy) might be the optimal strategy for patients with oligometastasis. It deserves prospective research to further validate the efficacy.

e16213 Background: Currently nab-paclitaxel/gemcitabine (AG) is the standard first-line treatment for advanced pancreatic ductal adenocarcinoma (aPDAC), which is still needed to improve. The phase Ib/II study aiming to evaluate safety and efficacy of AG plus toripalimab, an anti-PD-1 monoclonal antibody, showed well tolerability and encouraging efficacy in aPDAC patients (preliminary data presented at 2020 ASCO). Here, we updated new results of this study. Methods: This was a single-arm, open-label, phase Ib/II clinical trial of AG with toripalimab as first-line treatment for aPDAC. Patients received toripalimab (240mg, Q3W), combined with AG (nab-paclitaxel 125 mg/m2, d1, d8 plus gemcitabine 1000 mg/m2, d1, d8) until the disease progresses/unacceptable toxicity or receiving toripalimab maintenance treatment. The primary objectives were safety and OS; the secondary objectives were ORR, DCR and PFS. Predictive biomarkers including MMR protein and PD-L1 expression, the tumor mutation burden (TMB) based on next-generation sequencing, genomic alteration signatures and the number of TILs were evaluated. Results: At data cutoff (Feb 3, 2021), 20 chemotherapy naïve aPDAC patients (female: 65.0%, median age: 55.5 years) with ECOG PS ≤ 2 were enrolled. Of the 17 evaluable patients, the ORR was 35.3%, the DCR was 82.4%, including 5 patients with PR and 1 patient with CR, respectively. 12 patients were alive and the study treatments for 9 patients were still ongoing. Median PFS was 5.0 months (95% CI：4.216-5.784), the 6-month PFS rate was 60%; median OS was 14.0 months (95% CI：9.445-18.555), the 1-year OS rate was 80%. 2 cases of pseudoprogression were observed. The most frequent treatment related adverse events were ALT elevation (35.0%), leukocytopenia (30.0%) metabolic disorder (25.0%) and hypothyroidism (25.0%). 4 patients (20.0%) experienced grade 3/4 TRAE (including myocardial enzyme elevation, neutropenia, vomiting and nausea). In the biomarker analysis, all patients were MMR-proficient status; 14 patients were evaluated for PD-L1 expression compared with PD-L1 negative cases (n = 5), PD-L1 positive cases (n = 9) did not show higher RR or longer PFS, responses were observed in both groups. 10 patients were investigated for NGS, 2 patients with TMB > 10 Muts/Mb, the most frequently mutated genes were KRAS (90%), TP53 (90%) and ARID1A (20%). Conclusions: The updated results of this phase Ib/II study provided preliminary evidence that toripalimab in combination with AG has a manageable safety profile consistent with known safety profile for each agent alone and demonstrates signals of clinical activity. The correlation between biomarkers with clinical efficacy are under investigation. The results supported ongoing combined treatment in aPDAC patients. Clinical trial information: ChiCTR2000032293.

Objective: To study therapeutic effect and safety of high intensity focused ultrasound (HIFU) combined Gemcitabine on unresectable pancreatic carcinoma (PC). Methods: Total 45 PC patients were randomly divided into 2 groups: experimental group (treating with HIFUT and gemcitabine, n=23), control group (treating with gemcitabine only, n=22). The therapeutic effects and clinical benefit rates in two groups were compared by using the Kaplan-Meier and Log-Rank tests, including the median survival time (MST), 6-month and 12-month survival rates. Results: Our results showed that MST and 6-month survival rates of experimental patients were significantly higher than that of control patients (8.91 vs 5.53 mths, 73.9 vs 40.9%, p<0.05). For the 12-month survival rates, no statistically difference was observed between the two groups (13.0 vs 4.5%, p>0.05). The clinical benefit rates in experimental group and control group were 69.6% and 36.3%, respectively (p<0.05). The pain remission rate in experimental group was significantly higher than in control group (65.2 vs. 31.8%, p<0.05). Conclusions: For treating pancreatic carcinoma, HIFUT combined gemcitabine is better than gemcitabine only. The former treatment (HIFUT combined gemcitabine) may become a better effective treatment strategy for treating unresectable pancreatic carcinoma.

Epstein-Barr virus-associated lymphoepithelioma-like intrahepatic cholangiocarcinoma (EBVa LEL-ICC) is a rare tumor, characterized by a rich tumor immune microenvironment (TIME). While this tumor is reportedly sensitive to immunotherapy, its response has been inconsistent. This decreased sensitivity was associated with reduced TIME abundance. We report the case of a 53-year-old woman with EBVa LEL-ICC having reduced TIME abundance. The patient presented with a liver lesion, which was detected using ultrasound. Initially, the tumor was sensitive to immunotherapy and chemotherapy (IC), but resistance developed after a short interval. Subsequently, stereotactic ablative radiotherapy (SABR) was added to the patient’s treatment, which now consisted of ICSABR. Successful tumor shrinkage was achieved with the combination therapy regimen. Thus, surgery and ICSABR are effective adjuncts to the first-line IC therapy in improving the survival rate of patients with EBVa LEL-ICC. The results of this study support multidisciplinary treatment as a viable treatment strategy for EBVa LEL-ICC.

IntroductionThe optimal dose and treatment modality of neoadjuvant radiotherapy applied for treating borderline resectable and locally advanced pancreatic ductal adenocarcinoma (PDAC) have been debated topics in oncology. The objective of the present network meta-analysis (NMA) is to study and compare the efficacy and safety of neoadjuvant radiotherapy comprehensively using different doses in patients with borderline resectable pancreatic cancer (BRPC) and locally advanced pancreatic cancer (LAPC).Methods and analysisFour electronic databases, including PubMed, EMBASE, Cochrane library and Web of science, will be searched thoroughly to identify relevant studies published from 2006 to October 2020. Electronic searching by titles using neoadjuvant treatments for PDAC will be performed in the annual meetings of European Society of Medical Oncology and American Society of Clinical Oncology (2018–2020). ClinicalTrials.gov will also be searched for grey literature. Two reviewers will perform search strategies and extract data independently. R0 resection rate and local control rate are defined as primary outcomes. Secondary outcomes include overall survival, disease-free survival and acute and late grade 3 and grade 4 toxicities. For randomised control trials, the risk of bias will be assessed using the Cochrane Risk of Bias Tool, while the risk of bias for non-randomised, observational studies will be evaluated using the Risk Of Bias In Non-randomised Studies-of Interventions. The quality of evidence will be evaluated using the version of Cochrane tool and Grades of Recommendation, Assessment, Development and Evaluation. Subgroup analysis and sensitivity analysis will be conducted in the present NMA.Ethics and disseminationThis study will synthesise the evidence regarding dose schedule of neoadjuvant radiotherapy in patients with BRPC and LAPC. We hope the findings from this NMA will help clinicians and patients select the optimal modality and dose schedule of neoadjuvant radiotherapy with respect to patient-reported outcomes. As no primary data collection will be undertaken, no ethics approval is required. The results will be disseminated through peer-reviewed journal.PROSPERO registration numberCRD42020222408.