Beyond Neutrophils for Predicting Relapse and Remission in Ulcerative Colitis.

BACKGROUND AND AIMS: This study examines colonic histological features in ulcerative colitis [UC] in endoscopic remission to determine which cell types and biopsy sites best predict a patient's likelihood of remaining in remission. METHODS: This is a retrospective chart, endoscopy and histology review of 166 patients with UC in endoscopic remission followed in a single inflammatory bowel disease practice over a median of 6 years [range, 2-11 years]. Clinical remission was based on global physician assessment and colonoscopy reports, and clinical relapse on chart review. Histological features of previous injury and also number and location of plasma cells and eosinophils were assessed. We evaluated all of these features semi-quantitatively using a standard set of illustrations for the grade to maintain consistency. Multiple logistic regression and survival analyses were used to identify features associated with relapse. RESULTS: Clinical relapse occurred in 44 patients. Ulceration, especially in the left colon, was highly predictive of relapse. In the absence of acute inflammation of ulceration, the variables most predictive of relapse were increased plasma cells in the basal 20% of the lamina propria, and eosinophils in the left colon. The variable most predictive of persistent remission was the presence of intra-epithelial eosinophils whether in the surface epithelium or within crypts, especially in the right colon. Lamina propria eosinophils [grade > 2] throughout the colon predicted relapse. CONCLUSION: In the absence of neutrophils or ulceration, left-sided plasmacytosis in the basal 20% of the lamina propria and increased lamina propria eosinophils provide the best indicators of relapse in UC in clinical and endoscopic remission.

Improving tumor budding reporting in colorectal cancer: a Delphi consensus study.

Tumor budding is a long-established independent adverse prognostic marker in colorectal cancer, yet methods for its assessment have varied widely. In an effort to standardize its reporting, a group of experts met in Bern, Switzerland, in 2016 to reach consensus on a single, international, evidence-based method for tumor budding assessment and reporting (International Tumor Budding Consensus Conference [ITBCC]). Tumor budding assessment using the ITBCC criteria has been validated in large cohorts of cancer patients and incorporated into several international colorectal cancer pathology and clinical guidelines. With the wider reporting of tumor budding, new issues have emerged that require further clarification. To better inform researchers and health-care professionals on these issues, an international group of experts in gastrointestinal pathology participated in a modified Delphi process to generate consensus and highlight areas requiring further research. This effort serves to re-affirm the importance of tumor budding in colorectal cancer and support its continued use in routine clinical practice.

Beyond Helicobacter: dealing with other variants of gastritis-an algorithmic approach.

In daily practice, the presence of inflammation in gastric biopsies prompts a mental algorithm, an early question being whether the lesion present is Helicobacter-associated. If Helicobacter organisms are not found, then there is a further algorithm, governed by the predominant type of inflammatory cells present, and the presence of other features such as intraepithelial lymphocytosis, a subepithelial collagen band, granulomas, coexisting chronic inflammation, focality, and superimposed reactive changes including erosions and ulcers. Each of these generates its own differential diagnosis. If no inflammation is present, then the two major changes specifically looked for are the changes associated with hypergastrinaemia, by far the most common cause of which is treatment with proton pump inhibitors, and reactive changes. These may be present with and without accompanying inflammation, and, when the epithelial changes dominate, the term gastropathy is preferred. In this article, we present an approach to non-Helicobacter inflammation and gastropathies.

Fit-For-Purpose PD-L1 Biomarker Testing For Patient Selection in Immuno-Oncology: Guidelines For Clinical Laboratories From the Canadian Association of Pathologists-Association Canadienne Des Pathologistes (CAP-ACP).

Since 2014, programmed cell death protein 1 (PD-1)/programmed cell death ligand 1 (PD-L1) checkpoint inhibitors have been approved by various regulatory agencies for the treatment of multiple cancers including melanoma, lung cancer, urothelial carcinoma, renal cell carcinoma, head and neck cancer, classical Hodgkin lymphoma, colorectal cancer, gastroesophageal cancer, hepatocellular cancer, and other solid tumors. Of these approved drug/disease combinations, a subset also has regulatory agency-approved, commercially available companion/complementary diagnostic assays that were clinically validated using data from their corresponding clinical trials. The objective of this document is to provide evidence-based guidance to assist clinical laboratories in establishing fit-for-purpose PD-L1 biomarker assays that can accurately identify patients with specific tumor types who may respond to specific approved immuno-oncology therapies targeting the PD-1/PD-L1 checkpoint. These recommendations are issued as 38 Guideline Statements that address (i) assay development for surgical pathology and cytopathology specimens, (ii) reporting elements, and (iii) quality assurance (including validation/verification, internal quality assurance, and external quality assurance). The intent of this work is to provide recommendations that are relevant to any tumor type, are universally applicable and can be implemented by any clinical immunohistochemistry laboratory performing predictive PD-L1 immunohistochemistry testing.

The differential diagnosis of Helicobacter pylori negative gastritis.

Gastric biopsies are often submitted with as clinical question Helicobacter pylori (HP) infection. Regularly, the morphology suggests a HP infection but the organism is not detected in special stains. This review presents a practical approach to deal with such biopsies. The first step is to exclude a false negative result of the search for HP, by ensuring that both antral and oxyntic mucosa are present, by the use of sensitive stains, identification of marked reactive changes, such as intestinal, pseudo-pyloric, pancreatic metaplasia that may suggest a diagnosis of (HP associated or autoimmune) atrophic gastritis, and finally identification of signs of the use of proton pump inhibitors (PPI) as in such biopsies, HP may sometimes be found only within parietal cells. The differential diagnosis should include lymphocytic gastritis, other diseases affecting the stomach, such as inflammatory bowel disease (IBD), vasculitis, granulomatous disease, viral infection, such as cytomegalovirus (CMV) or more rarely Epstein-Barr virus (EBV) infection, or other bacterial infections, such as Enterococcus and Treponema pallidum. Clinical input may be required to ensure the patient is not taking medication that may cause gastritis, such as antibiotics used for HP eradication or common medications that cause a form of gastropathy. When these have been excluded, a known cause has not been found and in such a case, the term idiopathic focal/diffuse gastritis can be used.

Risk factors for esophageal cancer: emphasis on infectious agents.

Risk factors for esophageal cancer include genetic factors (such as tylosis) and infectious agents. A variety of organisms have been implicated in esophageal carcinogenesis, either directly or indirectly. In this review, we explore the normal esophageal flora and how it may be controlled, and also the variety of organisms that may affect esophageal carcinogenesis, either directly or indirectly. The organisms with potential direct effects in squamous cell carcinoma include human papillomavirus (HPV), Epstein-Barr virus, and polyoma viruses. Interestingly, HPV is now implicated in esophageal adenocarcinoma (EAC), not in its initiation but in the development of dysplasia, in which HPV33 in particular has been associated. Indirectly, Helicobacter pylori has been associated with EAC by, initially, causing increased acid secretion that increases acid reflux, and by reducing lower esophageal sphincter pressure, which increases gastroesophageal reflux; the latter increases the risk of Barrett's esophagus, and hence EAC. Conversely, subsequent atrophic gastritis may normalize that risk.

Recommendations for reporting tumor budding in colorectal cancer based on the International Tumor Budding Consensus Conference (ITBCC) 2016.

Tumor budding is a well-established independent prognostic factor in colorectal cancer but a standardized method for its assessment has been lacking. The primary aim of the International Tumor Budding Consensus Conference (ITBCC) was to reach agreement on an international, evidence-based standardized scoring system for tumor budding in colorectal cancer. The ITBCC included nine sessions with presentations, a pre-meeting survey and an e-book covering the key publications on tumor budding in colorectal cancer. The 'Grading of Recommendation Assessment, Development and Evaluation' method was used to determine the strength of recommendations and quality of evidence. The following 10 statements achieved consensus: tumor budding is defined as a single tumor cell or a cell cluster consisting of four tumor cells or less (22/22, 100%). Tumor budding is an independent predictor of lymph node metastases in pT1 colorectal cancer (23/23, 100%). Tumor budding is an independent predictor of survival in stage II colorectal cancer (23/23, 100%). Tumor budding should be taken into account along with other clinicopathological features in a multidisciplinary setting (23/23, 100%). Tumor budding is counted on H&E (19/22, 86%). Intratumoral budding exists in colorectal cancer and has been shown to be related to lymph node metastasis (22/22, 100%). Tumor budding is assessed in one hotspot (in a field measuring 0.785 mm2) at the invasive front (22/22, 100%). A three-tier system should be used along with the budding count in order to facilitate risk stratification in colorectal cancer (23/23, 100%). Tumor budding and tumor grade are not the same (23/23, 100%). Tumor budding should be included in guidelines/protocols for colorectal cancer reporting (23/23, 100%). Members of the ITBCC were able to reach strong consensus on a single international, evidence-based method for tumor budding assessment and reporting. It is proposed that this method be incorporated into colorectal cancer guidelines/protocols and staging systems.

Eosinophilic esophagitis: current perspectives from diagnosis to management.

Eosinophilic esophagitis (EoE) is a chronic antigen-mediated immune disease of the esophagus characterized by symptoms related to esophageal dysfunction, as well as significant esophageal eosinophilia. Although dense eosinophilia is the hallmark of EoE, other characteristic histologic features have been described that may help distinguish EoE from other competing diagnoses, although none are specific to EoE. One or more foods and, at times, environmental allergens trigger EoE. Left untreated, esophageal inflammation in EoE may lead to esophageal remodeling and stricture formation. Symptoms in EoE vary with age, as they relate to the progression of the disease from an inflammatory to a fibrostenotic phenotype over time. There are currently no U.S. Food and Drug Administration-approved therapies for EoE. Current options include various dietary-restriction therapies, topical corticosteroids, and esophageal dilations. Several emerging therapies aiming at restoring the esophageal barrier function or targeting various inflammatory cells or their mediators are under investigation.

Appropriateness of using patient-derived xenograft models for pharmacologic evaluation of novel therapies for esophageal/gastro-esophageal junction cancers.

The high morbidity and mortality of patients with esophageal (E) and gastro-esophageal junction (GEJ) cancers, warrants new pre-clinical models for drug testing. The utility of primary tumor xenografts (PTXGs) as pre-clinical models was assessed. Clinicopathological, immunohistochemical markers (p53, p16, Ki-67, Her-2/neu and EGFR), and global mRNA abundance profiles were evaluated to determine selection biases of samples implanted or engrafted, compared with the underlying population. Nine primary E/GEJ adenocarcinoma xenograft lines were further characterized for the spectrum and stability of gene/protein expression over passages. Seven primary esophageal adenocarcinoma xenograft lines were treated with individual or combination chemotherapy. Tumors that were implanted (n=55) in NOD/SCID mice had features suggestive of more aggressive biology than tumors that were never implanted (n=32). Of those implanted, 21/55 engrafted; engraftment was associated with poorly differentiated tumors (p=0.04) and older patients (p=0.01). Expression of immunohistochemical markers were similar between patient sample and corresponding xenograft. mRNA differences observed between patient tumors and first passage xenografts were largely due to loss of human stroma in xenografts. mRNA patterns of early vs late passage xenografts and of small vs large tumors of the same passage were similar. Complete resistance was present in 2/7 xenografts while the remaining tumors showed varying degrees of sensitivity, that remained constant across passages. Because of their ability to recapitulate primary tumor characteristics during engraftment and across serial passaging, PTXGs can be useful clinical systems for assessment of drug sensitivity of human E/GEJ cancers.

Canadian Association of Pathologists-Association canadienne des pathologistes National Standards Committee for High Complexity Testing/Immunohistochemistry: guidelines for the preparation, release, and storage of unstained archived diagnostic tissue sections for immunohistochemistry.

OBJECTIVES: Formalin-fixed, paraffin-embedded unstained archived diagnostic tissue sections are frequently exchanged between clinical laboratories for immunohistochemical staining. The manner in which such sections are prepared represents a type of preanalytical variable that must be taken into account given the growing importance of immunohistochemical assays, especially predictive and prognostic tests, in personalized medicine. METHODS: Recommendations were derived from review of the literature and expert consensus of the Canadian Association of Pathologists-Association canadienne des pathologists National Standards Committee for High Complexity Testing/Immunohistochemistry. RESULTS: Relevant considerations include the type of glass slide on which to mount the unstained sections; the thickness of the tissue sections; the time from slide preparation to testing; the environment, particularly the temperature at which the unstained sections will be maintained prior to testing; the inclusion of on-slide positive control tissue where possible; and whether patient identifier(s) should be included on slide labels. CONCLUSIONS: Clear communication between requesting and releasing laboratories will facilitate the proper preparation of unstained sections and also ensure that applicable privacy considerations are addressed.

Infection and esophageal cancer.

The following, from the 12th OESO World Conference: Cancers of the Esophagus, includes commentaries on infection and cancer, and includes commentaries on the influence of bacterial infections on mucin expression and cancer risk; the role of esophageal bacterial biota in the incidence of esophageal disease; the association between human papilloma virus (HPV) and esophageal squamous cell carcinoma; the role of HPV in esophageal adenocarcinoma; the role of Helicobacter pylori in cardiac carcinoma; and the role of Epstein-Barr virus infection in esophageal cancer.

The esophageal mucosa and submucosa: immunohistology in GERD and Barrett's esophagus.

This paper presents commentaries on the microscopic morphology of esophageal squamous epithelium; the frequency of duplication of the muscularis mucosae (MM) in Barrett's esophagus (BE); the significance of multilayered epithelium; whether cells in the lamina propria reflect those in the epithelium; how stem cells are identified in the squamous esophagus; dilated intercellular spaces; the metastasizing potential of early carcinoma-dependent, molecular or immunohistochemical tests that improve diagnosis; the role of immunohistochemistry IHC in grading of neoplasia in Barrett's esophagus and defining the risk of progression to adenocarcinoma; the roles of CDX1 and CDX2 in squamous and cardiac mucosa; and the role of desmosomal cadherins and lectins in squamous and cardiac mucosa.

Gastric biopsies: the gap between evidence-based medicine and daily practice in the management of gastric Helicobacter pylori infection.

BACKGROUND: Many consider histology to be the gold standard for Helicobacter pylori detection. Because the number and distribution of H pylori organisms vary, particularly in patients taking proton pump inhibitors (PPIs), the American Gastroenterological Association recommends discontinuing PPIs two weeks before endoscopy, and taking biopsies from both the body and antrum. OBJECTIVE: To assess the influence of clinical practice on the histopathological detection of H pylori infection. METHODS: Electronic patient records were evaluated for the sites of gastric sampling and PPI use at endoscopy. One hundred fifty cases with biopsies taken from both antrum and body were randomly selected for pathological re-review with special stains. The gastric regions sampled, H pylori distribution and influence of clinical factors on pathological interpretation were assessed. RESULTS: Between 2005 and 2010, 10,268 biopsies were taken to detect H pylori. Only one region was sampled in 60% of patients (antrum 47%, body 13%). Re-review of biopsies taken from both antrum and body indicated that the correct regions were sampled in only 85 (57%) patients. Of these, 54 were H pylori positive and 96 were H pylori negative. H pylori was present in the antrum in only 15% of the patients and body only in 21%. Of 96 H pylori-negative patients, two were reinterpreted as positive. Forty-seven per cent of patients were taking PPIs at endoscopy, contributing to both false-negative and false-positive diagnoses. CONCLUSION: Despite national and international guidelines for managing H pylori infection, the American Gastroenterological Association guidelines are infrequently adhered to, with PPIs frequently contributing to false diagnosis; sampling one region only increases the likelihood of missing active infection by at least 15%.

Peritoneal elastic lamina invasion: limitations in its use as a prognostic marker in stage II colorectal cancer.

Peritoneal involvement in colorectal cancer (CRC) is an adverse prognostic feature, which may prompt consideration of adjuvant chemotherapy in stage II disease. Controversies and challenges surrounding its assessment have led to consideration of peritoneal elastic lamina invasion (ELI) as an alternative marker of advanced local spread. The objectives of this study were (1) to evaluate the prognostic significance of peritoneal ELI in stage II CRC and (2) to determine the feasibility of ELI assessment in routine practice with the use of an elastic stain. Two hundred seventeen patients with stage II CRC (186, pT3; 31, pT4) were assessed for ELI and other established adverse histologic features. Of the pT3 tumors, 31 (16.7%) were ELI positive, 121 (65%) were ELI negative, and 34 (18.3%) lacked an identifiable elastic lamina. There were no significant differences in disease-free survival between pT3 ELI-negative and ELI-positive tumors (P = .517). The disease-free survival of pT4 tumors was significantly lower than that of pT3 ELI-negative tumors (P = .024) and pT3 ELI-positive tumors (P = .026), respectively. The elastic lamina was detected less frequently in right-sided pT3 tumors compared with left-sided tumors (65/91 [71.4%] versus 87/95 [91.6%], P < .001). Right-sided tumors were also associated with a reduction in the staining intensity of the elastic lamina (P < .001). In conclusion, peritoneal ELI was not an adverse prognostic factor in this study. The frequent absence of an identifiable elastic lamina, particularly in right-sided tumors, may limit the use of ELI as a prognostic marker in CRC.

The phenotypic expression of inflammatory bowel disease in patients with primary sclerosing cholangitis differs in the distribution of colitis.

BACKGROUND: Inflammatory bowel disease (IBD) associated with primary sclerosing cholangitis (PSC) is reported to be mild and prone to right-side predominance with rectal sparing. However, no dedicated studies evaluating patterns of presentation of liver disease with respect to IBD are available. METHODS: We performed a detailed histological examination of the colonic biopsies in the context of PSC, identifying 97 patients [89 with ulcerative colitis and ten with Crohn's disease (CD)] stratified into two groups, based on their initial disease presentation: hepatic/biliary (group 1-PSC-IBD; n=56) versus colonic (group 2-IBD-PSC; n=41). RESULTS: Inflammatory bowel disease that preceded PSC had a tendency to have a "pan-colitis" distribution; this group included all patients with CD. Inflammatory bowel disease diagnosis that followed PSC presentation was more likely to be right-sided, sparing the descending, sigmoid and rectal regions (p=0.002). In both groups, colitis was mild with focal deep plasmacytosis and occasional mild cryptitis. Active cryptitis with crypt abscesses, surface erosion and ulceration were not identified in any of the patients. CONCLUSION: Colitis associated with PSC shows mild disease activity and the colitis pattern is associated with disease presentation, i.e. colitis preceding PSC (IBD-PSC cohort) typically have a pancolitic distribution, while colitis following PSC (PSC-IBD cohort) demonstrates right-sided predominance. Awareness by pathologists and clinicians of these patterns of inflammatory bowel disease is important and of use in directing appropriate investigations for patients.

Primary esophageal and gastro-esophageal junction cancer xenograft models: clinicopathological features and engraftment.

There are very few xenograft models available for the study of esophageal (E) and gastro-esophageal junction (GEJ) cancer. Using a NOD/SCID model, we implanted 90 primary E and GEJ tumors resected from patients and six endoscopic biopsy specimens. Of 69 resected tumors with histologically confirmed viable adenocarcinoma or squamous cell carcinoma, 22 (32%) was engrafted. One of 11 tumors, considered to have had a complete pathological response to neo-adjuvant chemo-radiation, also engrafted. Of the 23 patients whose tumors were engrafted, 65% were male; 30% were early stage while 70% were late stage; 22% received neo-adjuvant chemo-radiation; 61% were GEJ cancers. Engraftment occurred in 18/54 (33%) adenocarcinomas and 5/16 (31%) squamous cell carcinomas. Small endoscopic biopsy tissue had a 50% (3/6) engraftment rate. Of the factors analyzed, pretreatment with chemo-radiation and well/moderate differentiation showed significantly lower correlation with engraftment (P<0.05). In the subset of patients who did not receive neo-adjuvant chemo-radiation, 18/41 (44%) engrafted compared with those with pretreatment where 5/29 (17%, P=0.02) engrafted. Primary xenograft lines may be continued through 4-12 passages. Xenografts maintained similar histology and morphological characteristics with only minor variations even after multiple passaging in most instances.

Primary angiosarcoma of the esophagus.

Primary angiosarcoma of the esophagus is an extremely rare soft-tissue tumor with no previously documented cases in the MEDLINE and EMBASE databases as of April 2012. We report a case of primary esophageal angiosarcoma in an otherwise healthy 77-year-old woman presenting with odynophagia and epigastric discomfort.

Glucagon-like peptide-2 increases dysplasia in rodent models of colon cancer.

The intestinal hormone, glucagon-like peptide-2 (GLP-2), enhances intestinal growth and reduces inflammation in rodent models. Hence, a degradation-resistant GLP-2 analog is under investigation for treatment of Crohn's disease. However, GLP-2 increases colonic dysplasia in murine azoxymethane (AOM)-induced colon cancer. Considering the increased colon cancer risk associated with chronic colitis, we have therefore examined the effects of long-acting hGly(2)GLP-2, as well as of endogenous GLP-2 using the antagonist hGLP-2(3-33) in two novel models of inflammation-associated colon cancer: rats fed the carcinogen 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and a high-fat diet (HFD) for one or three cycles, and mice with chronic dextran sodium-sulfate (DSS)-induced colitis administered AOM. hGly(2)GLP-2 treatment of one-cycle PhIP/HFD rats increased the number of colonic aberrant crypt foci by 72 ± 11% (P < 0.01). Fifty-one weeks after three PhIP/HFD cycles, hGly(2)GLP-2-treated rats had a 22% incidence of colon cancer, compared with 0% in vehicle-treated rats. AOM-DSS mice treated with vehicle or hGly(2)GLP-2 had high-grade dysplasia/colon cancer incidences of 56 and 64%, respectively, compared with 46% in hGLP-2(3-33)-treated AOM-DSS animals (P < 0.05). Unexpectedly, hGLP-2(3-33) also reduced the colitis damage score by 32.0 ± 8.4% (P < 0.05). All high-grade dysplastic/cancerous tumors had nuclear localization of ß-catenin although ß-catenin mRNA transcript and protein levels did not differ between treatment groups. GLP-2 receptor mRNA expression also was not different. However, hGLP-2(3-33)-treated mice had markedly reduced numbers of doublecortin-and-calmodulin-kinase-like-1-positive stem cells, by 73.7 ± 8.6% (P < 0.05). In conclusion, the results of this study indicate a role for hGly(2)GLP-2 and endogenous GLP-2 as potential cancer promoters in rodents.

Adverse metabolic effects of a hypercaloric, high-fat diet in rodents precede observable changes in body weight.

Although a high-fat diet (HFD) is recognized as an important contributor to obesity, human research is limited by confounders such as income, whereas animal research has typically examined diet during specific developmental periods rather than throughout the lifespan. We hypothesized that the use of an HFD in short-term studies as has been commonly done in animals does not adequately reflect the lifelong dietary patterns seen frequently in humans with consequent metabolic disturbances. We examined the impact of HFD from weaning until 39 weeks (middle age) on the metabolism of male rats. At 7, 26, and 39 weeks, glucose tolerance tests were performed, a subset of animals was euthanized, and serum and tissues were collected. After 4 weeks, preceding increased body weight, HFD animals had increased intra-abdominal fat, triglycerides, and hyperglycemia. Hyperinsulinemia was insufficient to maintain normoglycemia, and beta cell mass and glucagon-like peptide 1 decreased over time in HFD and control animals. Despite lacking significant lipid abnormalities, nonalcoholic fatty liver disease was evident by 39 weeks. Our HFD model demonstrated that significant metabolic abnormalities may go undetected by current standard screening such as weighing and biochemistry.