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The proposed system for defining and recording perioperative complications associated with esophagectomy provides an infrastructure to standardize international data collection and facilitate future comparative studies and quality improvement projects.

Despite recent efforts to dissect the inter-tumor heterogeneity of pancreatic ductal adenocarcinoma (PDAC) by determining prognosis-predictive gene expression signatures for specific subtypes, their functional differences remain elusive. Here, we established a pancreatic tumor organoid library encompassing 39 patient-derived PDACs and identified 3 functional subtypes based on their stem cell niche factor dependencies on Wnt and R-spondin. A Wnt-non-producing subtype required Wnt from cancer-associated fibroblasts, whereas a Wnt-producing subtype autonomously secreted Wnt ligands and an R-spondin-independent subtype grew in the absence of Wnt and R-spondin. Transcriptome analysis of PDAC organoids revealed gene-expression signatures that associated Wnt niche subtypes with GATA6-dependent gene expression subtypes, which were functionally supported by genetic perturbation of GATA6. Furthermore, CRISPR-Cas9-based genome editing of PDAC driver genes (KRAS, CDKN2A, SMAD4, and TP53) demonstrated non-genetic acquisition of Wnt niche independence during pancreas tumorigenesis. Collectively, our results reveal functional heterogeneity of Wnt niche independency in PDAC that is non-genetically formed through tumor progression.

Mesenchymal stem cell (MSC) transplantation has been explored as a new clinical approach to repair injured tissue. A growing corpus of studies have highlighted two important aspects of MSC therapy: 1) MSCs can modulate T-cell-mediated immunological responses, and (2) systemically administered MSCs home to sites of ischemia or injury. In this review, we describe the known mechanisms of immunomodulation and homing of MSCs. First, we examine the low immunogenicity of MSCs and their antigen presentation capabilities. Next, we discuss the paracrine interactions between MSCs and innate [dendritic cells (DC)] and adaptive immune cells (T lymphocytes) with a focus on prostaglandin E 2 (PGE 2 ), indoleamine 2,3-dioxygenase (IDO), and toll-like receptor (TLR) signaling pathways. We transition to outline the steps of activation, rolling/ adhesion, and transmigration of MSCs into target tissues during inflammatory or ischemic conditions. These aspects of MSC grafts-immunomodulation and homing-are contextualized to understand a reported side effect of MSC therapy, cancer development.

Standardized methods provide contemporary international benchmarks for reporting outcomes after esophagectomy.

BACKGROUNDFirst-line chemotherapy for advanced esophageal squamous-cell carcinoma results in poor outcomes. The monoclonal antibody nivolumab has shown an overall survival benefit over chemotherapy in previously treated patients with advanced esophageal squamous-cell carcinoma. METHODSIn this open-label, phase 3 trial, we randomly assigned adults with previously untreated, unresectable advanced, recurrent, or metastatic esophageal squamouscell carcinoma in a 1:1:1 ratio to receive nivolumab plus chemotherapy, nivolumab plus the monoclonal antibody ipilimumab, or chemotherapy. The primary end points were overall survival and progression-free survival, as determined by blinded independent central review. Hierarchical testing was performed first in patients with tumor-cell programmed death ligand 1 (PD-L1) expression of 1% or greater and then in the overall population (all randomly assigned patients). RESULTSA total of 970 patients underwent randomization. At a 13-month minimum followup, overall survival was significantly longer with nivolumab plus chemotherapy than with chemotherapy alone, both among patients with tumor-cell PD-L1 expression of 1% or greater (median, 15.4 vs. 9.1 months; hazard ratio, 0.54; 99.5% confidence interval [CI], 0.37 to 0.80; P<0.001) and in the overall population (median, 13.2 vs. 10.7 months; hazard ratio, 0.74; 99.1% CI, 0.58 to 0.96; P = 0.002). Overall survival was also significantly longer with nivolumab plus ipilimumab than with chemotherapy among patients with tumor-cell PD-L1 expression of 1% or greater (median, 13.7 vs. 9.1 months; hazard ratio, 0.64; 98.6% CI, 0.46 to 0.90; P = 0.001) and in the overall population (median, 12.7 vs. 10.7 months; hazard ratio, 0.78; 98.2% CI, 0.62 to 0.98; P = 0.01). Among patients with tumor-cell PD-L1 expression of 1% or greater, a significant progression-free survival benefit was also seen with nivolumab plus chemotherapy over chemotherapy alone (hazard ratio for disease progression or death, 0.65; 98.5% CI, 0.46 to 0.92; P = 0.002) but not with nivolumab plus ipilimumab as compared with chemotherapy. The incidence of treatment-related adverse events of grade 3 or 4 was 47% with nivolumab plus chemotherapy, 32% with nivolumab plus ipilimumab, and 36% with chemotherapy alone. CONCLUSIONSBoth first-line treatment with nivolumab plus chemotherapy and first-line treatment with nivolumab plus ipilimumab resulted in significantly longer overall survival than chemotherapy alone in patients with advanced esophageal squamous-cell carcinoma, with no new safety signals identified. (Funded by Bristol Myers Squibb and Ono Pharmaceutical; CheckMate 648 ClinicalTrials.gov number, NCT03143153.

Although gastrointestinal stromal tumors (GISTs) are a rare type of cancer, they are the commonest sarcoma in the gastrointestinal tract. Molecularly targeted therapy, such as imatinib therapy, has revolutionized the treatment of advanced GIST and facilitates scientific research on GIST. Nevertheless, surgery remains a mainstay of treatment to obtain a permanent cure for GIST even in the era of targeted therapy. Many GIST guidelines have been published to guide the diagnosis and treatment of the disease. We review current versions of GIST guidelines published by the National Comprehensive Cancer Network, by the European Society for Medical Oncology, and in Japan. All clinical practice guidelines for GIST include recommendations based on evidence as well as on expert consensus. Most of the content is very similar, as represented by the following examples: GIST is a heterogeneous disease that may have mutations in KIT, PDGFRA, HRAS, NRAS, BRAF, NF1, or the succinate dehydrogenase complex, and these subsets of tumors have several distinctive features. Although there are some minor differences among the guidelines—for example, in the dose of imatinib recommended for exon 9-mutated GIST or the efficacy of antigen retrieval via immunohistochemistry—their common objectives regarding diagnosis and treatment are not only to improve the diagnosis of GIST and the prognosis of patients but also to control medical costs. This review describes the current standard diagnosis, treatment, and follow-up of GISTs based on the recommendations of several guidelines and expert consensus.

ObjectiveTo document the clinicopathologic characteristics and survival of patients undergoing esophagectomy for squamous carcinoma of the thoracic esophagus, and to examine the factors contributing to improvements in outcome noted in patients with advanced carcinoma. Summary Background DataJapanese and some Western surgeons recently have reported that radical esophagectomy with extensive lymphadenectomy conferred a survival advantage to patients with esophageal carcinoma. The factors contributing to this improvement in results have not been well defined. MethodsFrom 1981 to 1995, 419 patients with carcinoma of the thoracic esophagus underwent esophagectomy at the Keio University Hospital. The clinicopathologic characteristics and survival of patients treated between 1981 and 1987 were compared with those of patients treated between 1988 and 1995. Multivariate analysis using the Cox regression model was carried out to evaluate the impact of 15 variables on survival of patients with p stage IIa to IV disease. Several variables related to prognosis were examined to identify differences between the two time periods. ResultsThe 5-year survival rate for all patients was 40.0%. The 5-year survival rate was 17.7% for p stage IIa to IV patients treated during the earlier period and 37.6% for those treated during the latter period. The Cox regression model revealed seven variables to be important prognostic factors. Of these seven, three (severity of postoperative complications, degree of residual tumor, and number of dissected mediastinal nodes) were found to be significantly different between the earlier and latter periods. ConclusionsThe survival of patients undergoing surgery for advanced carcinoma (p stage IIa to IV) of the thoracic esophagus has improved during the past 15 years. The authors' data suggest that this improvement is due mainly to advances in surgical technique and perioperative management.In Japan, surgeons have the primary responsibility for treating patients with carcinoma of the thoracic esophagus. In the past two decades, advances in esophageal cancer surgery have been remarkable. These advances have included more accurate diagnostic and staging techniques, performance of radical esophagectomy with extensive lymphadenectomy, appropriate use of limited surgery, and improvements in perioperative management and adjuvant therapy. Consequently, a 5-year survival rate of more than 50% 1 has been reported in patients who underwent threefield dissection. The aim of our study was to analyze the management and outcome of patients with carcinoma of the thoracic esophagus who underwent esophagectomy during a recent 15-year period to identify the factors contributing to the improvement in the management of this tumor.