International Delphi consensus guidelines for follow-up after prophylactic total gastrectomy: the Life after Prophylactic Total Gastrectomy (LAP-TG) study.

BACKGROUND: Prophylactic total gastrectomy (PTG) remains the only means of preventing gastric cancer for people with genetic mutations predisposing to Hereditary Diffuse Gastric Cancer (HDGC), mainly in the CDH1 gene. The small but growing cohort of people undergoing PTG at a young age are expected to have a life-expectancy close to the general population, however, knowledge of the long-term effects of, and monitoring requirements after, PTG is limited. This study aims to define the standard of care for follow-up after PTG. METHODS: Through a combination of literature review and two-round Delphi consensus of major HDGC/PTG units and physicians, and patient advocates, we produced a set of recommendations for follow-up after PTG. RESULTS: There were 42 first round, and 62 second round, responses from clinicians, allied health professionals and patient advocates. The guidelines include recommendations for timing of assessments and specialties involved in providing follow-up, micronutrient supplementation and monitoring, bone health and the provision of written information. CONCLUSION: While the evidence supporting the guidelines is limited, expert consensus provides a framework to best manage people following PTG, and could support the collection of information on the long-term effects of PTG.

Development of a Reliable Surgical Quality Assurance System for 2-stage Esophagectomy in Randomized Controlled Trials.

OBJECTIVE: The aim was to develop a reliable surgical quality assurance system for 2-stage esophagectomy. This development was conducted during the pilot phase of the multicenter ROMIO trial, collaborating with international experts. SUMMARY OF BACKGROUND DATA: There is evidence that the quality of surgical performance in randomized controlled trials influences clinical outcomes, quality of lymphadenectomy and loco-regional recurrence. METHODS: Standardization of 2-stage esophagectomy was based on structured observations, semi-structured interviews, hierarchical task analysis, and a Delphi consensus process. This standardization provided the structure for the operation manual and video and photographic assessment tools. Reliability was examined using generalizability theory. RESULTS: Hierarchical task analysis for 2-stage esophagectomy comprised fifty-four steps. Consensus (75%) agreement was reached on thirty-nine steps, whereas fifteen steps had a majority decision. An operation manual and record were created. A thirty five-item video assessment tool was developed that assessed the process (safety and efficiency) and quality of the end product (anatomy exposed and lymphadenectomy performed) of the operation. The quality of the end product section was used as a twenty seven-item photographic assessment tool. Thirty-one videos and fifty-three photographic series were submitted from the ROMIO pilot phase for assessment. The overall G-coefficient for the video assessment tool was 0.744, and for the photographic assessment tool was 0.700. CONCLUSIONS: A reliable surgical quality assurance system for 2-stage esophagectomy has been developed for surgical oncology randomized controlled trials. ETHICAL APPROVAL: 11/NW/0895 and confirmed locally as appropriate, 12/SW/0161, 16/SW/0098.Trial registration number: ISRCTN59036820, ISRCTN10386621.

The role of staging laparoscopy in complex bariatric surgery.

Determining which patients will benefit from bariatric surgery is complex; however, in those who have had previous bariatric surgery or extensive abdominal surgery, this can be particularly challenging. Decisions are often made based on assumptions rather than a complete assessment of all the anatomical and physiological factors. Adopting the approach utilised in gastrointestinal surgery with a diagnostic or staging laparoscopy, it may be possible to more accurately stage disease and determine fitness bariatric surgery. Laparoscopy is relatively low risk and contributes critical information with regard to access, post-operative anatomical changes and response to anaesthetic. Additionally, it allows surgeons to accurately determine the feasibility of undertaking a procedure and facilitates a more precise discussion with patients regarding suitability for surgery. Denying patients bariatric procedures based on an incomplete assessment of risk is unfair. Scenarios in which patients have had previous surgery, particularly bariatric surgery are increasingly common with the numbers requiring revisional surgery steadily rising. Although only applicable in highly selected, very complex cases, diagnostic laparoscopy adds critical information in the preoperative assessment of patients, not only improving care but potentially widening the numbers considered eligible for bariatric surgery. Our limited experience with staging laparoscopy in patients with previous complex abdominal surgery requiring revisional surgery illustrates the potential benefit it offers in determining patient suitability for further bariatric procedures. The adoption of an established technique, applied in a novel setting offers surgeons the opportunity to more thoroughly assess potentially high risk patients as well as the ability to offer personalised care.

Acute appendicitis management during the COVID-19 pandemic: A prospective cohort study from a large UK centre.

BACKGROUND: During the Covid-19 pandemic, non-operative management for acute appendicitis (AA) was implemented in the UK. The aim of this study was to determine the efficacy and outcomes of conservative versus surgical management of AA during the pandemic. MATERIALS & METHODS: We conducted an observational study in a tertiary referral centre. Data was collected from all patients (≥16 years) with a diagnosis of AA between November 1, 2019 to March 10, 2020 (pre-COVID period) and March 10, 2020 to July 5, 2020 (COVID period). RESULTS: A total of 116 patients in the pre-COVID period were included versus 91 in the COVID period. 43.1% (n = 50) of patients pre-COVID were classified as ASA 2 compared to 26.4% (n = 24) during the COVID period (p-value = 0.042). 72.5% (n = 66) of the patients during the COVID period scored as high risk using the Alvarado score compared to 24.1% (n = 28) in the pre-COVID period (p-value<0.001). We observed a significant increase in radiological evaluation, 69.8% versus 87.5% of patients had a CT in the pre-COVID and COVID periods respectively (p-value = 0.008). 94.9% of patients were managed operatively in the pre-COVID period compared to 60.4% in the COVID period (p-value<0.001). We observed more open appendicectomies (37.3% versus 0.9%; p-value<0.001) during the COVID period compared to the pre-COVID period. More abscess formation and free fluid were found intraoperatively in the COVID period (p-value = 0.021 and 0.023 respectively). Re-attendance rate due to appendicitis-related issues was significantly higher in the COVID period (p = 0.027). CONCLUSION: Radiological diagnosis of AA was more frequent during the COVID period. More conservative management for AA was employed during the COVID-19 pandemic, and for those managed operatively an open approach was preferred. Intra-operative findings were suggestive of delayed presentation during the COVID period without this affecting the length of hospital stay.

Preclinical evaluation of the versius surgical system, a new robot-assisted surgical device for use in minimal access general and colorectal procedures.

OBJECTIVE: To evaluate the utility of a new robot-assisted surgical system (the Versius Surgical System, CMR Surgical, Cambridge, UK) for use in minimal access general and colorectal surgery, in a preclinical setting. Robot-assisted laparoscopy has been developed to overcome some of the important limitations of conventional laparoscopy. The new system is designed to assist surgeons in performing minimal access surgery and overcome some of the challenges associated with currently available surgical robots. METHODS: Cadaveric sessions were conducted to evaluate the ability of the system to provide adequate surgical access and reach required to complete a range of general and colorectal procedures. Port and bedside unit positions were recorded, and surgical access and reach were evaluated by the lead surgeon using a visual analogue scale. A live animal (porcine) model was used to assess the surgical device's safety in performing cholecystectomy or small bowel enterotomy. RESULTS: Nine types of procedure were performed in cadavers by nine lead surgeons; 35/38 procedures were completed successfully. The positioning of ports and bedside units reflected the lead surgeons' preferred laparoscopic set-up and enabled good surgical access and reach. Cholecystectomy (n = 6) and small bowel enterotomy (n = 5) procedures performed in pigs were all completed successfully by two surgeons. There were no device-related intra-operative complications. CONCLUSIONS: This preclinical study of a new robot-assisted surgical system for minimal access general and colorectal surgery demonstrated the safety and effectiveness of the system in cadaver and porcine models. Further studies are required to assess its clinical utility.

Hereditary diffuse gastric cancer: updated clinical practice guidelines.

Hereditary diffuse gastric cancer (HDGC) is an autosomal dominant cancer syndrome that is characterised by a high prevalence of diffuse gastric cancer and lobular breast cancer. It is largely caused by inactivating germline mutations in the tumour suppressor gene CDH1, although pathogenic variants in CTNNA1 occur in a minority of families with HDGC. In this Policy Review, we present updated clinical practice guidelines for HDGC from the International Gastric Cancer Linkage Consortium (IGCLC), which recognise the emerging evidence of variability in gastric cancer risk between families with HDGC, the growing capability of endoscopic and histological surveillance in HDGC, and increased experience of managing long-term sequelae of total gastrectomy in young patients. To redress the balance between the accessibility, cost, and acceptance of genetic testing and the increased identification of pathogenic variant carriers, the HDGC genetic testing criteria have been relaxed, mainly through less restrictive age limits. Prophylactic total gastrectomy remains the recommended option for gastric cancer risk management in pathogenic CDH1 variant carriers. However, there is increasing confidence from the IGCLC that endoscopic surveillance in expert centres can be safely offered to patients who wish to postpone surgery, or to those whose risk of developing gastric cancer is not well defined.

Mass spectrometric characterisation of the circulating peptidome following oral glucose ingestion in control and gastrectomised patients.

RATIONALE: Meal ingestion triggers secretion of a variety of gut and endocrine peptides important in diabetes research which are routinely measured by immunoassays. However, similarities between some peptides (glucagon, oxyntomodulin and glicentin) can cause specificity issues with immunoassays. We used a liquid chromatography/tandem mass spectrometry (LC/MS/MS) methodology to unambiguously monitor multiple gut peptides in human plasma. METHODS: A simple acetonitrile-based protein precipitation step, followed by evaporation and solid-phase extraction, removed high-abundance proteins from samples prior to nano-LC/MS/MS analysis on an Orbitrap Q-Exactive Plus mass spectrometer using a data-dependent methodology. Database searching using PEAKS identified multiple gut-derived peptides, including peptides in the mid-pg/mL range. The relative levels of these and previously characterised peptides were assessed in plasma samples from gastrectomised and control subjects during an oral glucose tolerance test. RESULTS: Analysis of plasma extracts revealed significantly elevated levels of a number of peptides following glucose ingestion in subjects who had undergone gastrectomy compared with controls. These included GLP-1(7-36), GLP-1(9-36), glicentin, oxyntomodulin, GIP(1-42), GIP(3-42), PYY(1-36), PYY(3-36), neurotensin, insulin and C-peptide. Motilin levels decreased following glucose ingestion. Results showed good correlation with immunoassay-derived concentrations of some peptides in the same samples. The gastrectomy group also had higher, but non-glucose-dependent, circulating levels of peptides from PIGR and DMBT1. CONCLUSIONS: Overall, the approach showed that a fast, generic and reproducible LC/MS/MS methodology requiring only a small volume of plasma was capable of the multiplexed detection of a variety of diabetes-related peptides.

Genomic evidence supports a clonal diaspora model for metastases of esophageal adenocarcinoma.

The poor outcomes in esophageal adenocarcinoma (EAC) prompted us to interrogate the pattern and timing of metastatic spread. Whole-genome sequencing and phylogenetic analysis of 388 samples across 18 individuals with EAC showed, in 90% of patients, that multiple subclones from the primary tumor spread very rapidly from the primary site to form multiple metastases, including lymph nodes and distant tissues-a mode of dissemination that we term 'clonal diaspora'. Metastatic subclones at autopsy were present in tissue and blood samples from earlier time points. These findings have implications for our understanding and clinical evaluation of EAC.

Characterisation of proguanylin expressing cells in the intestine - evidence for constitutive luminal secretion.

Guanylin, a peptide implicated in regulation of intestinal fluid secretion, is expressed in the mucosa, but the exact cellular origin remains controversial. In a new transgenic mouse model fluorescent reporter protein expression driven by the proguanylin promoter was observed throughout the small intestine and colon in goblet and Paneth(-like) cells and, except in duodenum, in mature enterocytes. In Ussing chamber experiments employing both human and mouse intestinal tissue, proguanylin was released predominantly in the luminal direction. Measurements of proguanylin expression and secretion in cell lines and organoids indicated that secretion is largely constitutive and requires ER to Golgi transport but was not acutely regulated by salt or other stimuli. Using a newly-developed proguanylin assay, we found plasma levels to be raised in humans after total gastrectomy or intestinal transplantation, but largely unresponsive to nutrient ingestion. By LC-MS/MS we identified processed forms in tissue and luminal extracts, but in plasma we only detected full-length proguanylin. Our transgenic approach provides information about the cellular origins of proguanylin, complementing previous immunohistochemical and in-situ hybridisation results. The identification of processed forms of proguanylin in the intestinal lumen but not in plasma supports the notion that the primary site of action is the gut itself.

Transcriptomic profiling reveals three molecular phenotypes of adenocarcinoma at the gastroesophageal junction.

Cancers occurring at the gastroesophageal junction (GEJ) are classified as predominantly esophageal or gastric, which is often difficult to decipher. We hypothesized that the transcriptomic profile might reveal molecular subgroups which could help to define the tumor origin and behavior beyond anatomical location. The gene expression profiles of 107 treatment-naïve, intestinal type, gastroesophageal adenocarcinomas were assessed by the Illumina-HTv4.0 beadchip. Differential gene expression (limma), unsupervised subgroup assignment (mclust) and pathway analysis (gage) were undertaken in R statistical computing and results were related to demographic and clinical parameters. Unsupervised assignment of the gene expression profiles revealed three distinct molecular subgroups, which were not associated with anatomical location, tumor stage or grade (p > 0.05). Group 1 was enriched for pathways involved in cell turnover, Group 2 was enriched for metabolic processes and Group 3 for immune-response pathways. Patients in group 1 showed the worst overall survival (p = 0.019). Key genes for the three subtypes were confirmed by immunohistochemistry. The newly defined intrinsic subtypes were analyzed in four independent datasets of gastric and esophageal adenocarcinomas with transcriptomic data available (RNAseq data: OCCAMS cohort, n = 158; gene expression arrays: Belfast, n = 63; Singapore, n = 191; Asian Cancer Research Group, n = 300). The subgroups were represented in the independent cohorts and pooled analysis confirmed the prognostic effect of the new subtypes. In conclusion, adenocarcinomas at the GEJ comprise three distinct molecular phenotypes which do not reflect anatomical location but rather inform our understanding of the key pathways expressed.

Important Role of the GLP-1 Axis for Glucose Homeostasis after Bariatric Surgery.

Bariatric surgery is widely used to treat obesity and improves type 2 diabetes beyond expectations from the degree of weight loss. Elevated post-prandial concentrations of glucagon-like peptide 1 (GLP-1), peptide YY (PYY), and insulin are widely reported, but the importance of GLP-1 in post-bariatric physiology remains debated. Here, we show that GLP-1 is a major driver of insulin secretion after bariatric surgery, as demonstrated by blocking GLP-1 receptors (GLP1Rs) post-gastrectomy in lean humans using Exendin-9 or in mice using an anti-GLP1R antibody. Transcriptomics and peptidomics analyses revealed that human and mouse enteroendocrine cells were unaltered post-surgery; instead, we found that elevated plasma GLP-1 and PYY correlated with increased nutrient delivery to the distal gut in mice. We conclude that increased GLP-1 secretion after bariatric surgery arises from rapid nutrient delivery to the distal gut and is a key driver of enhanced insulin secretion.

Comparison of Human and Murine Enteroendocrine Cells by Transcriptomic and Peptidomic Profiling.

Enteroendocrine cells (EECs) produce hormones such as glucagon-like peptide 1 and peptide YY that regulate food absorption, insulin secretion, and appetite. Based on the success of glucagon-like peptide 1-based therapies for type 2 diabetes and obesity, EECs are themselves the focus of drug discovery programs to enhance gut hormone secretion. The aim of this study was to identify the transcriptome and peptidome of human EECs and to provide a cross-species comparison between humans and mice. By RNA sequencing of human EECs purified by flow cytometry after cell fixation and staining, we present a first transcriptomic analysis of human EEC populations and demonstrate a strong correlation with murine counterparts. RNA sequencing was deep enough to enable identification of low-abundance transcripts such as G-protein-coupled receptors and ion channels, revealing expression in human EECs of G-protein-coupled receptors previously found to play roles in postprandial nutrient detection. With liquid chromatography-tandem mass spectrometry, we profiled the gradients of peptide hormones along the human and mouse gut, including their sequences and posttranslational modifications. The transcriptomic and peptidomic profiles of human and mouse EECs and cross-species comparison will be valuable tools for drug discovery programs and for understanding human metabolism and the endocrine impacts of bariatric surgery.

Benchmarking Complications Associated with Esophagectomy.

OBJECTIVE: Utilizing a standardized dataset with specific definitions to prospectively collect international data to provide a benchmark for complications and outcomes associated with esophagectomy. SUMMARY OF BACKGROUND DATA: Outcome reporting in oncologic surgery has suffered from the lack of a standardized system for reporting operative results particularly complications. This is particularly the case for esophagectomy affecting the accuracy and relevance of international outcome assessments, clinical trial results, and quality improvement projects. METHODS: The Esophageal Complications Consensus Group (ECCG) involving 24 high-volume esophageal surgical centers in 14 countries developed a standardized platform for recording complications and quality measures associated with esophagectomy. Using a secure online database (ESODATA.org), ECCG centers prospectively recorded data on all resections according to the ECCG platform from these centers over a 2-year period. RESULTS: Between January 2015 and December 2016, 2704 resections were entered into the database. All demographic and follow-up data fields were 100% complete. The majority of operations were for cancer (95.6%) and typically located in the distal esophagus (56.2%). Some 1192 patients received neoadjuvant chemoradiation (46.1%) and 763 neoadjuvant chemotherapy (29.5%). Surgical approach involved open procedures in 52.1% and minimally invasive operations in 47.9%. Chest anastomoses were done most commonly (60.7%) and R0 resections were accomplished in 93.4% of patients. The overall incidence of complications was 59% with the most common individual complications being pneumonia (14.6%) and atrial dysrhythmia (14.5%). Anastomotic leak, conduit necrosis, chyle leaks, recurrent nerve injury occurred in 11.4%, 1.3%, 4.7%, and 4.2% of cases, respectively. Clavien-Dindo complications ≥ IIIb occurred in 17.2% of patients. Readmissions occurred in 11.2% of cases and 30- and 90-day mortality was 2.4% and 4.5%, respectively. CONCLUSION: Standardized methods provide contemporary international benchmarks for reporting outcomes after esophagectomy.

International consensus on a complications list after gastrectomy for cancer.

BACKGROUND: Perioperative complications can affect outcomes after gastrectomy for cancer, with high mortality and morbidity rates ranging between 10 and 40%. The absence of a standardized system for recording complications generates wide variation in evaluating their impacts on outcomes and hinders proposals of quality-improvement projects. The aim of this study was to provide a list of defined gastrectomy complications approved through international consensus. METHODS: The Gastrectomy Complications Consensus Group consists of 34 European gastric cancer experts who are members of the International Gastric Cancer Association. A group meeting established the work plan for study implementation through Delphi surveys. A consensus was reached regarding a set of standardized methods to define gastrectomy complications. RESULTS: A standardized list of 27 defined complications (grouped into 3 intraoperative, 14 postoperative general, and 10 postoperative surgical complications) was created to provide a simple but accurate template for recording individual gastrectomy complications. A consensus was reached for both the list of complications that should be considered major adverse events after gastrectomy for cancer and their specific definitions. The study group also agreed that an assessment of each surgical case should be completed at patient discharge and 90 days postoperatively using a Complication Recording Sheet. CONCLUSION: The list of defined complications (soon to be validated in an international multicenter study) and the ongoing development of an electronic datasheet app to record them provide the basic infrastructure to reach the ultimate goals of standardized international data collection, establishment of benchmark results, and fostering of quality-improvement projects.

Germline pathogenic variants in PALB2 and other cancer-predisposing genes in families with hereditary diffuse gastric cancer without CDH1 mutation: a whole-exome sequencing study.

BACKGROUND: Germline pathogenic variants in the E-cadherin gene (CDH1) are strongly associated with the development of hereditary diffuse gastric cancer. There is a paucity of data to guide risk assessment and management of families with hereditary diffuse gastric cancer that do not carry a CDH1 pathogenic variant, making it difficult to make informed decisions about surveillance and risk-reducing surgery. We aimed to identify new candidate genes associated with predisposition to hereditary diffuse gastric cancer in affected families without pathogenic CDH1 variants. METHODS: We did whole-exome sequencing on DNA extracted from the blood of 39 individuals (28 individuals diagnosed with hereditary diffuse gastric cancer and 11 unaffected first-degree relatives) in 22 families without pathogenic CDH1 variants. Genes with loss-of-function variants were prioritised using gene-interaction analysis to identify clusters of genes that could be involved in predisposition to hereditary diffuse gastric cancer. FINDINGS: Protein-affecting germline variants were identified in probands from six families with hereditary diffuse gastric cancer; variants were found in genes known to predispose to cancer and in lesser-studied DNA repair genes. A frameshift deletion in PALB2 was found in one member of a family with a history of gastric and breast cancer. Two different MSH2 variants were identified in two unrelated affected individuals, including one frameshift insertion and one previously described start-codon loss. One family had a unique combination of variants in the DNA repair genes ATR and NBN. Two variants in the DNA repair gene RECQL5 were identified in two unrelated families: one missense variant and a splice-acceptor variant. INTERPRETATION: The results of this study suggest a role for the known cancer predisposition gene PALB2 in families with hereditary diffuse gastric cancer and no detected pathogenic CDH1 variants. We also identified new candidate genes associated with disease risk in these families. FUNDING: UK Medical Research Council (Sackler programme), European Research Council under the European Union's Seventh Framework Programme (2007-13), National Institute for Health Research Cambridge Biomedical Research Centre, Experimental Cancer Medicine Centres, and Cancer Research UK.

Gastrectomy with Roux-en-Y reconstruction as a lean model of bariatric surgery.

BACKGROUND: Altered enteroendocrine hormone responses are widely believed to underlie the beneficial effects of bariatric surgery in type 2 diabetes. While elevated postprandial glucagon-like peptide-1 (GLP-1) is considered one of the mediators, increased postprandial glucagon levels have recently been implicated. OBJECTIVES: We investigated hormonal responses in lean patients after prophylactic total gastrectomy (PTG), as a model of Roux-en-Y gastric bypass without the confounding effects of obesity or massive weight loss. SETTING: University hospital, United Kingdom. METHODS: Ten participants after PTG and 9 healthy volunteers were recruited for oral glucose tolerance tests. Plasma glucose, insulin, GLP-1, peptide YY, glucose-dependent insulinotropic-polypeptide, glucagon, oxyntomodulin, glucagon(1-61), and glicentin levels were assessed using immunoassays and/or mass spectrometry. RESULTS: PTG participants exhibited accelerated plasma glucose appearance, followed, in 3 of 10 cases, by hypoglycemia (<3 mM glucose). Plasma GLP-1, peptide YY, glucose-dependent insulinotropic-polypeptide, glicentin, and oxyntomodulin responses were elevated, and glucagon appeared to rise in PTG participants when measured with a glucagon-specific enzyme-linked immunosorbent assay. We revisited the specificity of this assay, and demonstrated significant cross-reactivity with glicentin and oxyntomodulin at concentrations observed in PTG plasma. Reassessment of glucagon with the same assay using a modified protocol, and by liquid chromatography-mass spectrometry, demonstrated suppression of glucagon secretion after oral glucose tolerance tests in both PTG and control cohorts. CONCLUSIONS: Care should be taken when assessing glucagon levels in the presence of elevated plasma levels of other proglucagon products. Substantial elevation of GLP-1 and insulin responses after PTG likely contribute to the observed hypoglycemia, and mirror similar hormone levels and complications observed in bariatric weight loss patients.

Comparative study of endoscopic surveillance in hereditary diffuse gastric cancer according to CDH1 mutation status.

BACKGROUND AND AIMS: Hereditary diffuse gastric cancer (HDGC) accounts for 1% of gastric cancer cases. For patients with a germline CDH1 mutation, risk-reducing gastrectomy is recommended. However, for those delaying surgery or for families with no causative mutation identified, regular endoscopy is advised. This study aimed to determine the yield of signet ring cell carcinoma (SRCC) foci in individuals with a CDH1 pathogenic variant compared with those without and how this varies with successive endoscopies. METHODS: Patients fulfilling HDGC criteria were recruited to a prospective longitudinal cohort study. Endoscopy was performed according to a strict protocol with visual inspection followed by focal lesion and random biopsy sampling to detect foci of SRCC. Survival analysis determined progression to finding of SRCC according to CDH1 mutation status. The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 and 36-item Short Form Health Survey questionnaires assessed quality of life before surveillance and each endoscopy. RESULTS: Eighty-five individuals fulfilling HDGC criteria underwent 201 endoscopies; 54 (63.5%) tested positive for CDH1 mutation. SRCC yield was 61.1% in CDH1 mutation carriers compared with 9.7% in noncarriers, and mutation-positive patients had a 10-fold risk of SRCC on endoscopy compared with those with no mutation detected (P < .0005). Yield of SRCC decreased substantially with subsequent endoscopies. Surveillance was associated with improved psychological health. CONCLUSIONS: SRCC foci are prevalent in CDH1 mutation carriers and can be detected at endoscopy using a standardized, multiple biopsy sampling protocol. Decreasing yield over time suggests that the frequency of endoscopy might be reduced. For patients with no CDH1 pathogenic variant detected, the cost-to-benefit ratio needs to be assessed in view of the low yield.

Volume-outcome revisited: The effect of hospital and surgeon volumes on multiple outcome measures in oesophago-gastric cancer surgery.

BACKGROUND: Most studies showing a volume outcome effect in resection surgery for oesophago-gastric cancer were conducted before the centralisation of clinical services. This study evaluated the relation between hospital- and surgeon volume and different risk-adjusted outcomes after oesophago-gastric (OG) cancer surgery in England between 2011 and 2013. METHODS: In data from the National Oesophago-Gastric Cancer Audit from the UK, multivariable random-effects logistic regression models were used to quantify the effect of surgeon and hospital volume on three outcomes: 30-day and 90-day mortality and anastomotic leakage. The models included patient risk factors to adjust for differences in case-mix among hospitals and surgeons. The between-cluster heterogeneity was estimated with the median odds ratio (MOR). RESULTS: The study included patients treated at 42 hospitals and 329 surgeons. The median (interquartile range) of the annual hospital and surgeon volumes were 110 patients (82 to 137) and 13 patients (8 to 19), respectively. The overall rates for 30-day and 90-day mortality were 2.3% and 4.4% respectively, and the anastomotic leakage was 6.3%. Higher hospital volume was associated with lower 30-day mortality (OR: 0.94; 95% CI: 0.91-0.98) and lower anastomotic leakage rates (OR: 0.96; 95% CI: 0.93-0.98) but not 90-day mortality. Higher surgeon volume was only associated with lower anastomotic leakage rates (OR: 0.81; 95% CI: 0.72-0.92). Hospital volume explained a part of the between-hospital variation in 30-day mortality whereas surgeon volume explained part of the between-hospital variation in anastomotic leakage. CONCLUSIONS: In the setting of centralized O-G cancer surgery in England, we could still observe an effect of volume on short-term outcomes. However, the effect is inconsistent, depending on the type of outcome measure under consideration, and much smaller than in previous studies. Efforts to centralise O-G cancer services further should carefully address the effects of both hospital and surgeon volume on the range of outcome measures that are relevant to patients.

A comparative analysis of whole genome sequencing of esophageal adenocarcinoma pre- and post-chemotherapy.

The scientific community has avoided using tissue samples from patients that have been exposed to systemic chemotherapy to infer the genomic landscape of a given cancer. Esophageal adenocarcinoma is a heterogeneous, chemoresistant tumor for which the availability and size of pretreatment endoscopic samples are limiting. This study compares whole-genome sequencing data obtained from chemo-naive and chemo-treated samples. The quality of whole-genomic sequencing data is comparable across all samples regardless of chemotherapy status. Inclusion of samples collected post-chemotherapy increased the proportion of late-stage tumors. When comparing matched pre- and post-chemotherapy samples from 10 cases, the mutational signatures, copy number, and SNV mutational profiles reflect the expected heterogeneity in this disease. Analysis of SNVs in relation to allele-specific copy-number changes pinpoints the common ancestor to a point prior to chemotherapy. For cases in which pre- and post-chemotherapy samples do show substantial differences, the timing of the divergence is near-synchronous with endoreduplication. Comparison across a large prospective cohort (62 treatment-naive, 58 chemotherapy-treated samples) reveals no significant differences in the overall mutation rate, mutation signatures, specific recurrent point mutations, or copy-number events in respect to chemotherapy status. In conclusion, whole-genome sequencing of samples obtained following neoadjuvant chemotherapy is representative of the genomic landscape of esophageal adenocarcinoma. Excluding these samples reduces the material available for cataloging and introduces a bias toward the earlier stages of cancer.