B cell immune profiles in dysbiotic vermiform appendixes of pancreatic cancer patients

Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest solid tumors and is resistant to immunotherapy. B cells play an essential role in PDAC progression and immune responses, both locally and systemically. Moreover, increasing evidence suggests that microbial compositions inside the tumor, as well as in the oral cavity and the gut, are important factors in shaping the PDAC immune landscape. However, the gut-associated lymphoid tissue (GALT) has not previously been explored in PDAC patients. In this study, we analyzed healthy vermiform appendix (VA) from 20 patients with PDAC and 32 patients with colon diseases by gene expression immune profiling, flow cytometry analysis, and microbiome sequencing. We show that the VA GALT of PDAC patients exhibits markers of increased inflammation and cytotoxic cell activity. In contrast, B cell function is decreased in PDAC VA GALT based on gene expression profiling; B cells express significantly fewer MHC class II surface receptors, whereas plasma cells express the immune checkpoint molecule HLA-G. Additionally, the vermiform appendix microbiome of PDAC patients is enriched with Klebsiella pneumoniae, Bifidobacterium animalis, and Adlercreutzia equolifaciens, while certain commensals are depleted. Our findings may suggest impaired B cell function within the GALT of PDAC patients, which could potentially be linked to microbial dysbiosis. Additional investigations are imperative to validate our observations and explore these potential targets of future therapies.</p

The Umbrella Siop-rtsg 2016 Wilms Tumour Pathology and Molecular Biology Protocol

On the basis of the results of previous national and international trials and studies, the Renal Tumour Study Group of the International Society of Paediatric Oncology (SIOP-RTSG) has developed a new study protocol for paediatric renal tumours: the UMBRELLA SIOP-RTSG 2016 protocol (the UMBRELLA protocol). Currently, the overall outcomes of patients with Wilms tumour are excellent, but subgroups with poor prognosis and increased relapse rates still exist. The identification of these subgroups is of utmost importance to improve treatment stratification, which might lead to reduction of the direct and late effects of chemotherapy. The UMBRELLA protocol aims to validate new prognostic factors, such as blastemal tumour volume and molecular markers, to further improve outcome. To achieve this aim, large, international, high-quality databases are needed, which dictate optimization and international harmonization of specimen handling and comprehensive sampling of biological material, refine definitions and improve logistics for expert review. To promote broad implementation of the UMBRELLA protocol, the updated SIOP-RTSG pathology and molecular biology protocol for Wilms tumours has been outlined, which is a consensus from the SIOP-RTSG pathology panel

Adherence to pre-set benchmark quality criteria to qualify as expert assessor of dysplasia in Barrett's esophagus biopsies - towards digital review of Barrett's esophagus

Background: Dysplasia assessment of Barrett's esophagus biopsies is associated with low observer agreement; guidelines advise expert review. We have developed a web-based review panel for dysplastic Barrett's esophagus biopsies. Objective: The purpose of this study was to test if 10 gastrointestinal pathologists working at Dutch Barrett's esophagus expert centres met pre-set benchmark scores for quality criteria. Methods: Ten gastrointestinal pathologists twice assessed 60 digitalized Barrett's esophagus cases, enriched for dysplasia; then randomised (7520 assessments). We tested predefined benchmark quality criteria: (a) percentage of 'indefinite for dysplasia' diagnoses, benchmark score ≤14% for all cases, ≤16% for dysplastic subset, (b) intra-observer agreement; benchmark score ≥0.66/≥0.39, (c) percentage agreement with 'gold standard diagnosis'; benchmark score ≥82%/≥73%, (d) proportion of cases with high-grade dysplasia underdiagnosed as non-dysplastic Barrett's esophagus; benchmark score ≤1/78 (≤1.28%) assessments for dysplastic subset. Results: Gastrointestinal pathologists had seven years' Barrett's esophagus-experience, handling seven Barrett's esophagus-cases weekly. Three met stringent benchmark scores; all cases and dysplastic subset, three met extended benchmark scores. Four pathologists lacked one quality criterion to meet benchmark scores. Conclusion: Predefined benchmark scores for expert assessment of Barrett's esophagus dysplasia biopsies are stringent and met by some gastrointestinal pathologists. The majority of assessors however, only showed limited deviation from benchmark scores. We expect further training with group discussions will lead to adherence of all participating gastrointestinal pathologists to quality criteria, and therefore eligible to join the review panel

Adherence to pre-set benchmark quality criteria to qualify as expert assessor of dysplasia in Barrett's esophagus biopsies - towards digital review of Barrett's esophagus

Background: Dysplasia assessment of Barrett's esophagus biopsies is associated with low observer agreement; guidelines advise expert review. We have developed a web-based review panel for dysplastic Barrett's esophagus biopsies. Objective: The purpose of this study was to test if 10 gastrointestinal pathologists working at Dutch Barrett's esophagus expert centres met pre-set benchmark scores for quality criteria. Methods: Ten gastrointestinal pathologists twice assessed 60 digitalized Barrett's esophagus cases, enriched for dysplasia; then randomised (7520 assessments). We tested predefined benchmark quality criteria: (a) percentage of 'indefinite for dysplasia' diagnoses, benchmark score ≤14% for all cases, ≤16% for dysplastic subset, (b) intra-observer agreement; benchmark score ≥0.66/≥0.39, (c) percentage agreement with 'gold standard diagnosis'; benchmark score ≥82%/≥73%, (d) proportion of cases with high-grade dysplasia underdiagnosed as non-dysplastic Barrett's esophagus; benchmark score ≤1/78 (≤1.28%) assessments for dysplastic subset. Results: Gastrointestinal pathologists had seven years' Barrett's esophagus-experience, handling seven Barrett's esophagus-cases weekly. Three met stringent benchmark scores; all cases and dysplastic subset, three met extended benchmark scores. Four pathologists lacked one quality criterion to meet benchmark scores. Conclusion: Predefined benchmark scores for expert assessment of Barrett's esophagus dysplasia biopsies are stringent and met by some gastrointestinal pathologists. The majority of assessors however, only showed limited deviation from benchmark scores. We expect further training with group discussions will lead to adherence of all participating gastrointestinal pathologists to quality criteria, and therefore eligible to join the review panel