Multiplex analysis of intratumoural immune infiltrate and prognosis in patients with stage II-III colorectal cancer from the SCOT and QUASAR 2 trials: a retrospective analysis.

BACKGROUND: Tumour-infiltrating CD8+ cytotoxic T cells confer favourable prognosis in colorectal cancer. The added prognostic value of other infiltrating immune cells is unclear and so we sought to investigate their prognostic value in two large clinical trial cohorts. METHODS: We used multiplex immunofluorescent staining of tissue microarrays to assess the densities of CD8+, CD20+, FoxP3+, and CD68+ cells in the intraepithelial and intrastromal compartments from tumour samples of patients with stage II-III colorectal cancer from the SCOT trial (ISRCTN59757862), which examined 3 months versus 6 months of adjuvant oxaliplatin-based chemotherapy, and from the QUASAR 2 trial (ISRCTN45133151), which compared adjuvant capecitabine with or without bevacizumab. Both trials included patients aged 18 years or older with an Eastern Cooperative Oncology Group performance status of 0-1. Immune marker predictors were analysed by multiple regression, and the prognostic and predictive values of markers for colorectal cancer recurrence-free interval by Cox regression were assessed using the SCOT cohort for discovery and QUASAR 2 cohort for validation. FINDINGS: After exclusion of cases without tissue microarrays and with technical failures, and following quality control, we included 2340 cases from the SCOT trial and 1069 from the QUASAR 2 trial in our analysis. Univariable analysis of associations with recurrence-free interval in cases from the SCOT trial showed a strong prognostic value of intraepithelial CD8 (CD8IE) as a continuous variable (hazard ratio [HR] for 75th vs 25th percentile [75vs25] 0·73 [95% CI 0·68-0·79], p=2·5 × 10-16), and of intrastromal FoxP3 (FoxP3IS; 0·71 [0·64-0·78], p=1·5 × 10-13) but not as strongly in the epithelium (FoxP3IE; 0·89 [0·84-0·96], p=1·5 × 10-4). Associations of other markers with recurrence-free interval were moderate. CD8IE and FoxP3IS retained independent prognostic value in bivariable and multivariable analysis, and, compared with either marker alone, a composite marker including both markers (CD8IE-FoxP3IS) was superior when assessed as a continuous variable (adjusted [a]HR75 vs 25 0·70 [95% CI 0·63-0·78], p=5·1 × 10-11) and when categorised into low, intermediate, and high density groups using previously published cutpoints (aHR for intermediate vs high 1·68 [95% CI 1·29-2·20], p=1·3 × 10-4; low vs high 2·58 [1·91-3·49], p=7·9 × 10-10), with performance similar to the gold-standard Immunoscore. The prognostic value of CD8IE-FoxP3IS was confirmed in cases from the QUASAR 2 trial, both as a continuous variable (aHR75 vs 25 0·84 [95% CI 0·73-0·96], p=0·012) and as a categorical variable for low versus high density (aHR 1·80 [95% CI 1·17-2·75], p=0·0071) but not for intermediate versus high (1·30 [0·89-1·88], p=0·17). INTERPRETATION: Combined evaluation of CD8IE and FoxP3IS could help to refine risk stratification in colorectal cancer. Investigation of FoxP3IS cells as an immunotherapy target in colorectal cancer might be merited. FUNDING: Medical Research Council, National Institute for Health Research, Cancer Research UK, Swedish Cancer Society, Roche, and Promedica Foundation.

Adding a Gene Expression Profile Test to Aid Differential Diagnosis and Treatment in Aggressive Large B-Cell Lymphoma: An Early Exploratory Economic Evaluation.

BACKGROUND AND OBJECTIVE: Adding gene expression profiles (GEPs) to the current diagnostic work-up of aggressive large B-cell lymphomas may lead to the reclassification of patients, treatment changes and improved outcomes. A GEP test is in development using TempO-Seq® technology to distinguish Burkitt lymphoma (BL) and primary mediastinal large B-cell lymphoma (PMBCL) from diffuse large B-cell lymphoma (DLBCL), and to classify patients with DLBLC and to predict the benefit of (e.g.) adding bortezomib to R-CHOP therapy (RB-CHOP). This study aims to estimate the potential impact of a GEP test on costs and health outcomes to inform pricing and evidence generation strategies. METHODS: Three decision models were developed comparing diagnostic strategies with and without GEP signatures over a lifetime horizon using a UK health and social care perspective. Inputs were taken from a recent clinical trial, literature and expert opinion. We estimated the maximum price of the test using a threshold of Great Britain Pound (GBP) 30,000 per quality-adjusted life-year (QALY). Sensitivity analyses were conducted. RESULTS: The estimated maximum threshold price for a combined test to be cost effective is GBP 15,352. At base-case values, the BL signature delivers QALY gains of 0.054 at an additional cost of GBP 275. This results in a net monetary benefit at a threshold of GBP 30,000 per QALY of GBP 1345. For PMBCL, the QALY gain was 0.0011 at a cost saving of GBP 406 and the net monetary benefit was GBP 437. The hazard ratio for the impact of treating BL less intensively must be at least 1.2 for a positive net monetary benefit. For identifying patients with the DLBCL subtype responsive to bortezomib, QALY gain was 0.2465 at a cost saving of GBP 6175, resulting in a net monetary benefit of GBP 13,570. In a probabilistic sensitivity analysis using 1000 simulations, a testing strategy was superior to a treat all with R-CHOP strategy in 81% of the simulations and with a cost saving in 92% assuming a cost price of zero. CONCLUSIONS: Our estimates show that the combined test has a high probability of being cost effective. There is good quality evidence for the benefit of subtyping DLBCL but the evidence on the number of patients reclassified to or from BL and PMBCL and the impact of a more precise diagnosis and the cost of treatment is weak. The developers can use the price estimate to inform a return on investment calculations. Evidence will be required of how well the TempO-Seq® technology performs compared to the testing GEP technology used for subtyping in the recent clinical trial. For BL and PMBCL elements of the test, evidence would be required of the number of patients reclassified and improved costing information would be useful. The diagnostic and therapeutic environment in haematological malignancies is fast moving, which increases the risk for developers of diagnostic tests.

An integrated gene-to-outcome multimodal database for metabolic dysfunction-associated steatotic liver disease.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the commonest cause of chronic liver disease worldwide and represents an unmet precision medicine challenge. We established a retrospective national cohort of 940 histologically defined patients (55.4% men, 44.6% women; median body mass index 31.3; 32% with type 2 diabetes) covering the complete MASLD severity spectrum, and created a secure, searchable, open resource (SteatoSITE). In 668 cases and 39 controls, we generated hepatic bulk RNA sequencing data and performed differential gene expression and pathway analysis, including exploration of gender-specific differences. A web-based gene browser was also developed. We integrated histopathological assessments, transcriptomic data and 5.67 million days of time-stamped longitudinal electronic health record data to define disease-stage-specific gene expression signatures, pathogenic hepatic cell subpopulations and master regulator networks associated with adverse outcomes in MASLD. We constructed a 15-gene transcriptional risk score to predict future hepatic decompensation events (area under the receiver operating characteristic curve 0.86, 0.81 and 0.83 for 1-, 3- and 5-year risk, respectively). Additionally, thyroid hormone receptor beta regulon activity was identified as a critical suppressor of disease progression. SteatoSITE supports rational biomarker and drug development and facilitates precision medicine approaches for patients with MASLD.

Audit of medical (non-targeted) liver biopsy specimen quality, pathology reporting and effect on patient management.

AIMS: To evaluate our medical liver pathology practice and its influence on patient management, using audit templates published by the UK Royal College of Pathologists (RCPath). METHODS: We audited medical liver biopsies reported in our centre in 2019 using RCPath proformas. Data were collected from pathology reports and corresponding electronic patient record. RESULTS: 60 cases were selected for audit from 135 eligible biopsies reported in 2019. 58/60 cases were core biopsies and 2/60 were laparoscopic wedge biopsies. 53/57 (93%) core biopsies with available data met RCPath adequacy criteria (length >15 mm and/or ≥6 portal tracts). Most reports (57/60; 95%) were judged to have helped patient management. 25/60 (42%) biopsy reports helped to clarify the clinical diagnosis and 48/60 (80%) led to altered management. CONCLUSIONS: We demonstrate the utility of the RCPath audit templates, highlighting the clinical value of medical liver biopsies in the diagnostic work-up and management of patients with liver disease.

Prognostic implications of microRNA-21 overexpression in pancreatic ductal adenocarcinoma: an international multicenter study of 686 patients.

Despite progress in genomic characterization, no single prognostic marker that can be evaluated using an easy-to-perform and relatively inexpensive method is available for pancreatic ductal adenocarcinoma (PDAC). MicroRNAs, which are stable, tumor- and tissue-specific molecules, are potentially ideal biomarkers, and we established an inter-laboratory validated method to investigate miR-21 as a prognostic biomarker in PDAC. The study samples of PDAC patients were recruited from a test cohort of Glasgow (n = 189) and three validation cohorts of Pisa (n = 69), Sydney (n = 249), and International Cancer Genome Consortium (ICGC) (n = 249). Tissue microarrays were used for miR-21 staining by chromogenic in situ hybridization (CISH). The patients were subdivided into no/low and high miR-21 staining groups using a specific histoscore. Furthermore, miR-21 staining was evaluated against clinicopathological variables and follow-up data by Fisher/log-rank test and Cox proportional models. The prognostic variables found to be significant in univariate analysis (P value < 0.10) were included in multivariate analysis in a backward-stepwise fashion. MiR-21 expression was cytoplasmic, with more consistent staining in the malignant ductal epithelium than in the stroma. The expression of miR-21 was significantly associated with tumor size and lymph node metastasis, whereas no association was observed with other clinicopathological variables. High miR-21 staining (histoscore ≥ 45 [median score]) was an independent predictor of survival in the Glasgow test cohort (HR 2.37, 95% CI: 1.42-3.96, P < 0.0001) and three validation cohorts (Pisa, HR 2.03, 95% CI: 1.21-3.39, P = 0.007; Sydney, HR 2.58, 95% CI (1.21-3.39), P < 0.0001; and ICGC, HR 3.34, 95% CI: 2.07-5.84, P = 0.002) when adjusted for clinical variables in a multivariate model. In comparison to the patients with low miR-21, the patients with high miR-21 expression had significant increase in OS as they benefit from gemcitabine-based adjuvant chemotherapy (Glasgow 16.5 months [with chemotherapy] vs 10.5 months [without chemotherapy]); Sydney 25.0 vs 10.6; ICGC 25.2 vs 11.9. These results indicated that miR-21 is a predictor of survival, prompting prospective trials. Evaluation of miR-21 offers new opportunities for the stratification of patients with PDAC and might facilitate the implementation of clinical management and therapeutic interventions for this devastating disease.

Alternative tissue fixation for combined histopathological and molecular analysis in a clinically representative setting.

Formalin is the principal tissue fixative used worldwide for clinical and research purposes. Despite optimal preservation of morphology, its preservation of DNA and RNA is poor. As clinical diagnostics increasingly incorporates molecular-based analysis, the requirement for maintaining nucleic acid quality is of increasing importance. Here we assess an alternative non-formalin-based tissue fixation method, PAXgene Tissue system, with the aim of better preserving nucleic acids, while maintaining the quality of the tissue to be used for vital existing diagnostic techniques. In this study, these criteria are assessed in a clinically representative setting. In total, 203 paired PAXgene Tissue and formalin-fixed samples were obtained. Blind-scored haematoxylin and eosin (H&E) sections showed comparable and acceptable staining. Immunohistochemistry (IHC) staining was suboptimal using existing protocols but improved with minor method adjustment and optimisation. Quality of DNA and RNA was significantly improved by PAXgene tissue fixation [RIN 2.8 versus 3.8 (p < 0.01), DIN 5.68 versus 6.77 (p < 0.001)], which translated into improved performance on qPCR assay. These results demonstrate the potential of PAXgene Tissue to be used routinely in place of formalin, maintaining adequate histological staining and significantly improving the preservation of biological molecules in the genomic era.

Creation of a novel simple heat mapping method for curriculum mapping, using pathology teaching as the exemplar.

BACKGROUND: The undergraduate five-year MBChB programme at the University of Glasgow has a high volume of pathology teaching integrated into the course. The ability to better understand what pathology is taught and when, so as to build a picture of the types and depth of pathology topics covered across the programme stages is crucial, especially in a spiral curriculum. A novel method of curriculum mapping, known as curriculum heat mapping, was developed as a way to visualise where and when topics are taught, in an easier to understand format. METHODS: This method involved comparing the Glasgow curriculum to a pre-determined standard of what should be taught. In this case, The Royal College of Pathologists' 'Pathology Undergraduate Curriculum' was used as a comparison of what a graduating doctor should know about pathology. RESULTS: Following the developed template, heat maps showcasing the range of pathology topics covered, and where they are covered, were developed for local use. These heat maps provided a clear visual representation of where and when topics are taught, and how they cluster. CONCLUSIONS: Heat mapping is a novel low-cost, high-input method of curriculum mapping. It requires a person to input the data which can take a long time for large curricula. There are no other upfront financial costs. It can be used in any area with a curriculum and an external or internal comparator. Examples of gold standard external comparators include validated national or international curricula. Heat mapping can help integrated, spiral curriculum programmes to identify where core topics are taught throughout their course. The heat maps themselves successfully demonstrate the required information and are easy to interpret. The process of mapping, as well as the final heat map, can yield important information. This includes information about trends within the curriculum, areas for potential improvement in sessional design and a clearer understanding of the depth to which each topic is covered in each lecture. Overall, it is a viable novel method, which has been successful locally and is easily transferable to other areas such as pharmacology.

Pathology and regulation for research in the UK: an overview.

The input of pathologists is essential for the conduct of many forms of research, including clinical trials. As the custodians of patient samples, pathology departments have a duty to ensure compliance with the relevant regulations, standards and guidelines to ensure the ethical and effective use for their intended investigational analysis, including when patients are participating in a research study. The results of research studies have impacts beyond the research study itself as they may inform changes in policy and practice or support the licensing of medicines and devices. Compliance with regulations and standards provides public assurance that the rights, safety and wellbeing of research participants are protected, that the data have been collected and processed to ensure their integrity and that the research will achieve its purpose. The requirements of the regulatory environment should not be seen as a barrier to research and should not significantly impact on the work of the laboratory once established and integrated into practice. This paper highlights important regulations, policy, standards and available guidance documents that apply to research involving NHS pathology departments and academic laboratories that are contributing to research involving human subjects.

CM-Path Molecular Diagnostics Forum-consensus statement on the development and implementation of molecular diagnostic tests in the United Kingdom.

BACKGROUND: Pathology has evolved from a purely morphological description of cellular alterations in disease to our current ability to interrogate tissues with multiple 'omics' technologies. By utilising these techniques and others, 'molecular diagnostics' acts as the cornerstone of precision/personalised medicine by attempting to match the underlying disease mechanisms to the most appropriate targeted therapy. METHODS: Despite the promises of molecular diagnostics, significant barriers have impeded its widespread clinical adoption. Thus, the National Cancer Research Institute (NCRI) Cellular Molecular Pathology (CM-Path) initiative convened a national Molecular Diagnostics Forum to facilitate closer collaboration between clinicians, academia, industry, regulators and other key stakeholders in an attempt to overcome these. RESULTS: We agreed on a consensus 'roadmap' that should be followed during development and implementation of new molecular diagnostic tests. We identified key barriers to efficient implementation and propose possible solutions to these. In addition, we discussed the recent reconfiguration of molecular diagnostic services in NHS England and its likely impacts. CONCLUSIONS: We anticipate that this consensus statement will provide practical advice to those involved in the development of novel molecular diagnostic tests. Although primarily focusing on test adoption within the United Kingdom, we also refer to international guidelines to maximise the applicability of our recommendations.

Survey of UK histopathology consultants' attitudes towards academic and molecular pathology.

OBJECTIVE: Academic pathology is facing a crisis; an ongoing decline in academic pathology posts, a paucity of academic pathologist's in-training and unfilled posts at a time when cellular pathology departments are challenged to deliver increasing numbers of molecular tests. The National Cancer Research Institute initiative in Cellular & Molecular Pathology commissioned a survey to assess attitudes of cellular pathology consultants towards research in order to understand barriers and identify possible solutions to improve this situation. As cellular pathology is encompassing an increasing number of diagnostic molecular tests, we also surveyed the current approach to and extent of training in molecular pathology. METHODS: The survey was distributed to all UK-based consultant pathologists via the Pathological Society of Great Britain & Ireland and Royal College of Pathologist networks. Heads of Department were contacted separately to obtain figures for number of academic training and consultant posts. RESULTS: 302 cellular pathologists completed the survey which represents approximately 21% of the total cellular histopathology workforce. Most respondents (89%) had been involved in research at some point; currently, 22% were undertaking research formally, and 41% on an informal basis. Of those previously involved in research, 57% stopped early in their consultant career. The majority of substantive academic posts were Professors of which 60% had been in post for >20 years. Most respondents (84%) used molecular pathology in diagnostic work, independent of where they worked or the length of time in post. Notably, 53% of consultants had not received molecular pathology training, particularly more senior consultants and consultants in district general hospitals. CONCLUSIONS: The survey reveals that the academic workforce is skewed towards senior individuals, many of whom are approaching retirement, with a missing cohort of 'junior consultant' academic pathologists to replace them. Most pathologists stop formal research activity at the beginning of a consultant career. While molecular pathology is an increasing part of a pathologist's workload, the majority of consultant cellular pathologists have not received any formal molecular training.

Barriers to the release of human tissue for clinical trials research in the UK: a national survey of cellular pathology laboratories on behalf of the National Cancer Research Institute's Cellular Molecular Pathology (CM-Path) initiative.

AIM: To survey UK cellular pathology departments regarding their attitudes and practices relating to release of human tissue from their diagnostic archives for use in clinical trial research. METHODS: A 30-item questionnaire was circulated to the National Cancer Research Institute's Cellular Molecular Pathology initiative and Confederation of Cancer Biobanks mailing lists. Responses were collected over a 10-month period from November 2016 to August 2017. RESULTS: 38 departments responded to the survey, the majority of which regularly receive requests for tissue for research purposes. Most requests come from academia and financial support to facilitate tissue release comes from a variety of sources. A range of practices were reported in relation to selection of the most appropriate sample to release, consent checking, costing and governance frameworks. CONCLUSIONS: This survey demonstrates wide variation in practice across the UK and identifies barriers to release of human tissue for clinical trial research. Until we can overcome these obstacles, patient samples will remain inaccessible to research. Therefore, this study highlights the urgent need for clear and coordinated national guidance on this issue.

Somatic cancer genetics in the UK: real-world data from phase I of the Cancer Research UK Stratified Medicine Programme.

INTRODUCTION: Phase I of the Cancer Research UK Stratified Medicine Programme (SMP1) was designed to roll out molecular pathology testing nationwide at the point of cancer diagnosis, as well as facilitate an infrastructure where surplus cancer tissue could be used for research. It offered a non-trial setting to examine common UK cancer genetics in a real-world context. METHODS: A total of 26 sites in England, Wales and Scotland, recruited samples from 7814 patients for genetic examination between 2011 and 2013. Tumour types involved were breast, colorectal, lung, prostate, ovarian cancer and malignant melanoma. Centralised molecular testing of surplus material from resections or biopsies of primary/metastatic tissue was performed, with samples examined for 3-5 genetic alterations deemed to be of key interest in site-specific cancers by the National Cancer Research Institute Clinical Study groups. RESULTS: 10 754 patients (98% of those approached) consented to participate, from which 7814 tumour samples were genetically analysed. In total, 53% had at least one genetic aberration detected. From 1885 patients with lung cancer, KRAS mutation was noted to be highly prevalent in adenocarcinoma (37%). In breast cancer (1873 patients), there was a striking contrast in TP53 mutation incidence between patients with ductal cancer (27.3%) and lobular cancer (3.4%). Vast inter-tumour heterogeneity of colorectal cancer (1550 patients) was observed, including myriad double and triple combinations of genetic aberrations. Significant losses of important clinical information included smoking status in lung cancer and loss of distinction between low-grade and high-grade serous ovarian cancers. CONCLUSION: Nationwide molecular pathology testing in a non-trial setting is feasible. The experience with SMP1 has been used to inform ongoing CRUK flagship programmes such as the CRUK National Lung MATRIX trial and TRACERx.

Digital pathology access and usage in the UK: results from a national survey on behalf of the National Cancer Research Institute's CM-Path initiative.

AIM: To canvass the UK pathology community to ascertain current levels of digital pathology usage in clinical and academic histopathology departments, and prevalent attitudes to digital pathology. METHODS: A 15-item survey was circulated to National Health Service and academic pathology departments across the UK using the SurveyMonkey online survey tool. Responses were sought at a departmental or institutional level. Where possible, departmental heads were approached and asked to complete the survey, or forward it to the most relevant individual in their department. Data were collected over a 6-month period from February to July 2017. RESULTS: 41 institutes from across the UK responded to the survey. 60% (23/39) of institutions had access to a digital pathology scanner, and 60% (24/40) had access to a digital pathology workstation. The most popular applications of digital pathology in current use were undergraduate and postgraduate teaching, research and quality assurance. Investigating the deployment of digital pathology in their department was identified as a high or highest priority by 58.5% of institutions, with improvements in efficiency, turnaround times, reporting times and collaboration in their institution anticipated by the respondents. Access to funding for initial hardware, software and staff outlay, pathologist training and guidance from the Royal College of Pathologists were identified as factors that could enable respondent institutions to increase their digital pathology usage. CONCLUSION: Interest in digital pathology adoption in the UK is high, with usage likely to increase in the coming years. In light of this, pathologists are seeking more guidance on safe usage.

Time for change: a new training programme for morpho-molecular pathologists?

The evolution of cellular pathology as a specialty has always been driven by technological developments and the clinical relevance of incorporating novel investigations into diagnostic practice. In recent years, the molecular characterisation of cancer has become of crucial relevance in patient treatment both for predictive testing and subclassification of certain tumours. Much of this has become possible due to the availability of next-generation sequencing technologies and the whole-genome sequencing of tumours is now being rolled out into clinical practice in England via the 100 000 Genome Project. The effective integration of cellular pathology reporting and genomic characterisation is crucial to ensure the morphological and genomic data are interpreted in the relevant context, though despite this, in many UK centres molecular testing is entirely detached from cellular pathology departments. The CM-Path initiative recognises there is a genomics knowledge and skills gap within cellular pathology that needs to be bridged through an upskilling of the current workforce and a redesign of pathology training. Bridging this gap will allow the development of an integrated 'morphomolecular pathology' specialty, which can maintain the relevance of cellular pathology at the centre of cancer patient management and allow the pathology community to continue to be a major influence in cancer discovery as well as playing a driving role in the delivery of precision medicine approaches. Here, several alternative models of pathology training, designed to address this challenge, are presented and appraised.

A33 shows similar sensitivity to but is more specific than CDX2 as an immunomarker of colorectal carcinoma.

AIMS: CDX2 is widely used as a sensitive and specific immunomarker for colorectal carcinoma (CRC), but neither its sensitivity nor its specificity is absolute. The aim of this study was to compare CDX1 and A33 with CDX2 as immunomarkers for CRC. METHODS AND RESULTS: As a pilot study, whole sections of 51 cases of liver metastatic carcinoma with different origins-colorectum (n = 32), breast (n = 3), oesophagogastric tract (n = 4), lung (n = 3), pancreas (n = 8), and prostate (n = 1)-were immunostained with CDX1, CDX2, and A33. A33 showed higher sensitivity as a CRC immunomarker, greater interobserver reproducibility for assessment of expression and less background cross-reactivity than CDX1. Therefore, only A33 was compared with CDX2 for a tissue microarray (TMA)-based study of primary adenocarcinomas with different origins: CRC (n = 55), liver deposits of metastatic CRC (n = 60), breast (n = 101), lung (n = 40), oesophagogastric tract (n = 134), ovary (n = 67), pancreas (n = 77), and prostate (n = 56). When the whole section and TMA cases of CRC were combined, A33 had a sensitivity of 95.9% and CDX2 had a sensitivity of 97.2%. When the whole section and TMA cases of non-colorectal carcinomas were combined, A33 had a specificity of 85.4% as a marker of CRC and CDX2 had a specificity of 64.3%. The higher specificity of A33 than of CDX2 as a CRC immunomarker was particularly seen among pancreatic and ovarian carcinomas. Furthermore, unlike what was seen with CDX2, none of the prostatic and lung carcinomas studied showed A33 positivity. CONCLUSIONS: A33 shows similar sensitivity to but is more specific than CDX2 as an immunomarker of CRC.

Investigating Various Thresholds as Immunohistochemistry Cutoffs for Observer Agreement.

BACKGROUND: Clinical translation of immunohistochemistry (IHC) biomarkers requires reliable and reproducible cutoffs or thresholds for interpretation of immunostaining. Most IHC biomarker research focuses on the clinical relevance (diagnostic, prognostic, or predictive utility) of cutoffs, with less emphasis on observer agreement using these cutoffs. From the literature, we identified 3 commonly used cutoffs of 10% positive epithelial cells, 20% positive epithelial cells, and moderate to strong staining intensity (+2/+3 hereafter) to use for investigating observer agreement. MATERIALS AND METHODS: A series of 36 images of microarray cores stained for 4 different IHC biomarkers, with variable staining intensity and percentage of positive cells, was used for investigating interobserver and intraobserver agreement. Seven pathologists scored the immunostaining in each image using the 3 cutoffs for positive and negative staining. Kappa (κ) statistic was used to assess the strength of agreement for each cutoff. RESULTS: The interobserver agreement between all 7 pathologists using the 3 cutoffs was reasonably good, with mean κ scores of 0.64, 0.59, and 0.62, respectively, for 10%, 20%, and +2/+3 cutoffs. A good agreement was observed for experienced pathologists using the 10% cutoff, and their agreement was statistically higher than for junior pathologists (P=0.02). In addition, the mean intraobserver agreement for all 7 pathologists using the 3 cutoffs was reasonably good, with mean κ scores of 0.71, 0.60, and 0.73, respectively, for 10%, 20%, and +2/+3 cutoffs. For all 3 cutoffs, a positive correlation was observed with perceived ease of interpretation (P<0.003). Finally, cytoplasmic-only staining achieved higher agreement using all 3 cutoffs than mixed staining patterns. CONCLUSIONS: All 3 cutoffs investigated achieve reasonable strength of agreement, modestly decreasing interobserver and intraobserver variability in IHC interpretation. These cutoffs have previously been used in cancer pathology, and this study provides evidence that these cutoffs can be reproducible between practicing pathologists.

A Glasgow Tipple-transjugular intrahepatic portosystemic shunt insertion prior to Whipple resection.

Abdominal surgery performed in patients with significant liver disease and portal hypertension is associated with high mortality rates, with even poorer outcomes associated with complex pancreaticobiliary operations. We report on a patient requiring portal decompression via transjugular intrahepatic portosystemic shunt (TIPS) prior to a pancreaticoduodenectomy. The 49-year-old patient presented with pain, jaundice and weight loss. At ERCP an edematous ampulla was biopsied, revealing high-grade dysplasia within a distal bile duct adenoma. Liver biopsy was performed to investigate portal hypertension, confirming congenital hepatic fibrosis (CHF). A TIPS was performed to enable a pancreaticoduodenectomy. Prophylactic TIPS can be performed for preoperative portal decompression for patients requiring pancreatic resection. A potentially curative resection was performed when abdominal surgery was initially thought impossible. Notably, CHF has been associated with the development of cholangiocarcinoma in only four previous instances, with this case being only the second reported distal bile duct cholangiocarcinoma.

Ampullary Cancers Harbor ELF3 Tumor Suppressor Gene Mutations and Exhibit Frequent WNT Dysregulation.

The ampulla of Vater is a complex cellular environment from which adenocarcinomas arise to form a group of histopathologically heterogenous tumors. To evaluate the molecular features of these tumors, 98 ampullary adenocarcinomas were evaluated and compared to 44 distal bile duct and 18 duodenal adenocarcinomas. Genomic analyses revealed mutations in the WNT signaling pathway among half of the patients and in all three adenocarcinomas irrespective of their origin and histological morphology. These tumors were characterized by a high frequency of inactivating mutations of ELF3, a high rate of microsatellite instability, and common focal deletions and amplifications, suggesting common attributes in the molecular pathogenesis are at play in these tumors. The high frequency of WNT pathway activating mutation, coupled with small-molecule inhibitors of ß-catenin in clinical trials, suggests future treatment decisions for these patients may be guided by genomic analysis.