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BackgroundAccording to the Lauren classification, gastric adenocarcinomas are divided into diffuse and intestinal types. The causative attribution explaining the dismal prognosis of diffuse-type remains unknown.MethodsWe examined the archive of 1000 patients with gastric adenocarcinomas who received radical gastrectomy in our center and assessed the effect of the Lauren classification on survival in a multivariate approach. Moreover we compared the variation of clinical features between the diffuse-type and intestinal-type and explored the contributing factors for the prognostic difference.ResultsThere were 805 resectable patients for the final analysis. Diffuse-type comprised of 48.7% in the gastric carcinoma in our group and showed poorer prognosis than intestinal-type (P=0.013). Multivariate analysis revealed that independent prognostic factors for gastric carcinoma patients were T stage (P<0.001), N stage (P<0.001) tumor size (P<0.001) and Lauren classification (P=0.003). For the clinical features, diffuse-type was significantly associated with younger age (p<0.001), female preponderance (p <0.001), distal location (P<0.001), advanced pT (p < 0.001), advanced pN (p < 0.001) and advanced TNM stage (p = 0.027).ConclusionsDiffuse type adenocarcinoma carries a worse prognosis that may be partially explained by the tendency of this subtype to present at more advanced T and N stage. However, Lauren classification has prognostic significance that is independent of T and N stage as well as other prognostic variables based on the multivariate cox analysis.

The aim of present study was to examine whether the C-reactive protein (CRP)-based systemic inflammatory response such as the Glasgow Prognostic Score (GPS; a combination of CRP and albumin) offers prognostic value that is superior to the circulating white cellular components as neutrophil/lymphocyte ratio (NLR) or platelet/lymphocyte ratio (PLR) in patients undergoing resection for stage III gastric cancer. The medical records of 324 patients with stage III gastric adenocarcinoma were reviewed. Potential prognosis factors were evaluated with the Kaplan-Meier methodology and multivariable Cox hazards model. An increase of GPS was associated with an increase weight loss, higher NLR, higher PLR, and larger tumor size. On multivariate analysis, only the GPS, tumor-nodes-metastasis staging, and adjuvant chemotherapy were associated independently with disease-free and overall survival. However, the NLR and PLR were not. In subgroup analysis, patients with a GPS of 2 had a significantly poorer median survival (13.70 months) when compared with patients with a GPS of 1 (27.4 months) or 0 (median survival had not been reached) in patients who had received adjuvant chemotherapy. Our study demonstrated that elevated preoperative GPS is superior to circulating white cellular components and was associated with reduced overall and disease-free survival for patients with stage III gastric cancer.

ObjectiveTo monitor trastuzumab resistance and determine the underlying mechanisms for the limited response rate and rapid emergence of resistance of HER2+ metastatic gastric cancer (mGC).DesignTargeted sequencing of 416 clinically relevant genes was performed in 78 paired plasma and tissue biopsy samples to determine plasma-tissue concordance. Then, we performed longitudinal analyses of 97 serial plasma samples collected from 24 patients who were HER2+  to track the resistance during trastuzumab treatment and validated the identified candidate resistance genes.ResultsThe results from targeted sequencing-based detection of somatic copy number alterations (SCNA) of HER2 gene were highly consistent with fluorescence in situ hybridisation data, and the detected HER2 SCNA was better than plasma carcinoembryonic antigen levels at predicting tumour shrinkage and progression. Furthermore, most patients with innate trastuzumab resistance presented high HER2 SCNA during progression compared with baseline, while HER2 SCNA decreased in patients with acquired resistance. PIK3CA mutations were significantly enriched in patients with innate resistance, and ERBB2/4 genes were the most mutated genes, accounting for trastuzumab resistance in six (35.3%) and five (29.4%) patients in baseline and progression plasma, respectively. Patients with PIK3CA/R1/C3 or ERBB2/4 mutations in the baseline plasma had significantly worse progression-free survival. Additionally, mutations in NF1 contributed to trastuzumab resistance, which was further confirmed through in vitro and in vivo studies, while combined HER2 and MEK/ERK blockade overcame trastuzumab resistance.ConclusionLongitudinal circulating tumour DNA sequencing provides novel insights into gene alterations underlying trastuzumab resistance in HER2+mGC.

The hematogenous metastatic pattern of gastric cancer (GC) was not fully explored. Here we analyzed the frequency and clinicopathological features of metastasis to liver, lung, bone, and brain from GC patients. Data queried for this analysis included GC patients from the Surveillance, Epidemiology, and End Results Program database from 2010 to 2014. All of statistical analyses were performed using the Intercooled Stata 13.0 (Stata Corporation, College Station, TX). All statistical tests were two‐sided. Totally, there were 19 022 eligible patients for analysis. At the time of diagnosis, there were 7792 patients at stage IV, including 3218 (41.30%) patients with liver metastasis, 1126 (14.45%) with lung metastasis, 966 (12.40%) with bone metastasis and 151 (1.94%) with brain metastasis. GC patients with lung or liver metastasis have a higher risk of bone and brain metastasis than those without lung nor liver metastasis. Intestinal subtype had significantly higher rate of liver and lung metastasis, while diffuse type was more likely to have bone metastasis. Proximal stomach had significantly higher risk to develop metastasis than distal stomach. African‐Americans had the highest risk of liver metastasis and Caucasian had the highest prone to develop lung and brain metastasis. The median survival for patients with liver, lung, bone, and brain metastasis was 4 months, 3 months, 4 months and 3 months, respectively. It is important to evaluate the status of bone and brain metastasis in GC patients with lung or liver metastasis. Knowledge of metastatic patterns is helpful for clinicians to design personalized pretreatment imaging evaluation for GC patients.