Objective Resection can potentially cure resectable pancreatic cancer (PaC) and significantly prolong survival in some patients. This large-scale international study aimed to investigate variations in resection for PaC in Europe and USA and determinants for its utilisation. Design Data from six European population-based cancer registries and the US Surveillance, Epidemiology, and End Results Program database during 2003–2016 were analysed. Age-standardised resection rates for overall and stage I–II PaCs were computed. Associations between resection and demographic and clinical parameters were assessed using multivariable logistic regression models. Results A total of 153 698 records were analysed. In population-based registries in 2012–2014, resection rates ranged from 13.2% (Estonia) to 21.2% (Slovenia) overall and from 34.8% (Norway) to 68.7% (Denmark) for stage I–II tumours, with great international variations. During 2003–2014, resection rates only increased in USA, the Netherlands and Denmark. Resection was significantly less frequently performed with more advanced tumour stage (ORs for stage III and IV versus stage I–II tumours: 0.05–0.18 and 0.01–0.06 across countries) and increasing age (ORs for patients 70–79 and ≥80 versus those <60 years: 0.37–0.63 and 0.03–0.16 across countries). Patients with advanced-stage tumours (stage III–IV: 63.8%–81.2%) and at older ages (≥70 years: 52.6%–59.5%) receiving less frequently resection comprised the majority of diagnosed cases. Patient performance status, tumour location and size were also associated with resection application. Conclusion Rates of PaC resection remain low in Europe and USA with great international variations. Further studies are warranted to explore reasons for these variations.

Purpose: Elevated levels of neutrophils have been associated with poor survival in various cancers, but direct evidence supporting a role for neutrophils in the immunopathogenesis of human cancers is lacking. Experimental Design: A total of 573 patients with gastric cancer were enrolled in this study. Immunohistochemistry and real-time PCR were performed to analyze the distribution and clinical relevance of neutrophils in different microanatomic regions. The regulation and function of neutrophils were assessed both in vitro and in vivo. Results: Increased neutrophil counts in the peripheral blood were associated with poor prognosis in gastric cancer patients. In gastric cancer tissues, neutrophils were enriched predominantly in the invasive margin, and neutrophil levels were a powerful predictor of poor survival in patients with gastric cancer. IL17+ neutrophils constitute a large portion of IL17-producing cells in human gastric cancer. Proinflammatory IL17 is a critical mediator of the recruitment of neutrophils into the invasive margin by CXC chemokines. Moreover, neutrophils at the invasive margin were a major source of matrix metalloproteinase-9, a secreted protein that stimulates proangiogenic activity in gastric cancer cells. Accordingly, high levels of infiltrated neutrophils at the invasive margin were positively correlated with angiogenesis progression in patients with gastric cancer. Conclusions: These data provide direct evidence supporting the pivotal role of neutrophils in gastric cancer progression and reveal a novel immune escape mechanism involving fine-tuned collaborative action between cancer cells and immune cells in the distinct tumor microenvironment. Clin Cancer Res; 23(6); 1575–85. ©2016 AACR.

Gastric cancer (GC) is the fourth most common human malignant disease and the second leading cause of cancer-related deaths worldwide.¹ Surgical resection is the primary treatment for resectable GC; however, even after complete resection, a subset of patients will develop local recurrences and metachronous metastases.² For proper postoperative surveillance and treatment, it is necessary to develop prognostic tools to characterize the heterogeneity of GC.

Purpose: Current tumor–node–metastasis (TNM) staging system cannot provide adequate information for prediction of prognosis and chemotherapeutic benefits. We constructed a classifier to predict prognosis and identify a subset of patients who can benefit from adjuvant chemotherapy. Experimental Design: We detected expression of 15 immunohistochemistry (IHC) features in tumors from 251 gastric cancer (GC) patients and evaluated the association of their expression level with overall survival (OS) and disease-free survival (DFS). Then, integrating multiple clinicopathologic features and IHC features, we used support vector machine (SVM)–based methods to develop a prognostic classifier (GC-SVM classifier) with features. Further validation of the GC-SVM classifier was performed in two validation cohorts of 535 patients. Results: The GC-SVM classifier integrated patient sex, carcinoembryonic antigen, lymph node metastasis, and the protein expression level of eight features, including CD3_{invasive margin (IM)}, CD3_{center of tumor (CT)}, CD8_IM, CD45RO_CT, CD57_IM, CD66b_IM, CD68_CT, and CD34. Significant differences were found between the high- and low-GC-SVM patients in 5-year OS and DFS in training and validation cohorts. Multivariate analysis revealed that the GC-SVM classifier was an independent prognostic factor. The classifier had higher predictive accuracy for OS and DFS than TNM stage and can complement the prognostic value of the TNM staging system. Further analysis revealed that stage II and III GC patients with high-GC-SVM were likely to benefit from adjuvant chemotherapy. Conclusions: The newly developed GC-SVM classifier was a powerful predictor of OS and DFS. Moreover, the GC-SVM classifier could predict which patients with stage II and III GC benefit from adjuvant chemotherapy. Clin Cancer Res; 1–11. ©2018 AACR.