Paraneoplastic thrombocytosis is associated with increased mortality and increased rate of lymph node metastasis in oesophageal adenocarcinoma

Paraneoplastic thrombocytosis has been associated with adverse outcomes in several cancers, but has not been described in oesophageal adenocarcinoma. The aim of our study was to examine the prognostic value of platelet counts in patients with oesophageal adenocarcinoma. A cohort of 584 patients who underwent oesophagectomy for oesophageal adenocarcinoma was identified. Platelet counts, history of neoadjuvant chemoradiation, and clinicopathological factors such as T and N stage, and overall survival were recorded. Patients with elevated platelet count (>450,000/μL) had a higher mortality rate than patients with normal platelet count (150,000-450,000/μL) (hazard ratio = 2.60, p = 0.0013). This effect was seen in patients with and without neoadjuvant chemoradiation therapy. Paraneoplastic thrombocytosis was also associated with increased likelihood of lymph node metastasis compared to normal platelet count (69% versus 31%, p < 0.01). Paraneoplastic thrombocytosis is associated with increased rate of lymph node metastasis and mortality in oesophageal adenocarcinoma. Further studies are needed to examine the mechanisms behind this phenomenon.

Morphological Features and Prognostic Significance of ARID1A-Deficient Esophageal Adenocarcinomas

Context.—

The clinicopathologic and prognostic significance of ARID1A mutation in esophageal adenocarcinoma (EAC) is unknown.

Objective.—

To determine the morphological correlates and prognostic significance of ARID1A-deficient EAC.

Design.—

One hundred twenty cases of primary EAC were evaluated for a predetermined set of histologic features and immunohistochemistry for ARID1A, p53, and MLH1 performed on EAC, as well as adjacent Barrett esophagus and Barrett esophagus–associated dysplasia, when feasible. Associations between categorical clinicopathologic variables were analyzed by Fisher exact test, and survival analysis was performed by a Cox proportional hazards analysis.

Results.—

The study group included 97 men and 23 women (mean age, 66 years). Loss of ARID1A expression was seen in 12 of 120 EACs (10%). ARID1A-deficient tumors showed a strong correlation with a medullary and mucinous phenotype, and 8 of 12 (67%) had at least one feature reminiscent of high microsatellite instability colon carcinomas (mucinous or medullary differentiation, marked intratumoral or peritumoral lymphoid infiltrate). A mutant p53 pattern was present in 52 of 120 EACs (43%) and showed no correlation with ARID1A deficiency (P &gt; .05). MLH1 loss was present in only 2 of 120 EACs (2%); both of which were also deficient in ARID1A. ARID1A-deficient EACs showed a trend toward increased risk of nodal metastasis but had no effect on overall patient survival.

Conclusions.—

ARID1A-deficient EACs show a phenotype similar to colon cancer with high microsatellite instability but do not appear to have any prognostic significance. Concurrent MLH1 loss is not seen in most ARID1A-deficient tumors, suggesting that ARID1A may be a primary driver of carcinogenesis in a subset of EACs.

Discordance Among Pathologists in the United States and Europe in Diagnosis of Low-Grade Dysplasia for Patients With Barrett's Esophagus

BACKGROUND & AIMS

There is suboptimal inter-observer agreement, even among expert gastrointestinal pathologists, in the diagnosis of low-grade dysplasia (LGD) in patients with Barrett's esophagus (BE). We analyzed histopathologic criteria required for a diagnosis of LGD using the new subcategories of LGD with inflammatory and dysplastic features. We categorized each diagnosis based on the level of confidence and assessed inter-observer agreement among gastrointestinal pathologists from 5 tertiary centers in the United States and Europe.

METHODS

In the first phase of the study, 3 pathologists held a consensus conference at which they discussed the diagnostic criteria for LGD. In the second phase, 79 slides from patients with BE (23 samples of non-dysplastic BE, 22 samples of LGD, and 34 samples of high-grade dysplasia) were identified, randomly assigned to 7 pathologists (4 from the United States and 3 from Europe), and interpreted in a blinded fashion. κ Values were calculated for inter-observer agreement. We performed multinomial logistic regression analysis to assess the weighting of histologic features with the diagnosis.

RESULTS

The overall κ value for diagnosis was 0.43 (95% confidence interval [CI], 0.42-0.48). When categorized based on degree of dysplasia, the κ value was 0.22 (95% CI, 0.11-0.29) for non-dysplastic BE, 0.11 (95% CI, 0.004-0.15) for LGD, and 0.43 (95% CI, 0.36-0.46) for high-grade dysplasia. When all pathologists made a diagnosis with high confidence, the inter-observer agreement was substantial among the US pathologists (κ, 0.63; 95% CI, 0.61-0.66) and European pathologists (κ, 0.80; 95% CI, 0.74-0.97). The κ values for all diagnoses made by European pathologists were higher than those made by US pathologists.

CONCLUSIONS

In an analysis of criteria used in histopathologic diagnosis of LGD, we did not observe improvement in level of agreement among experienced pathologists, even after accounting for inflammation. The level of inter-observer agreement increased with level of pathologist confidence. There was also a difference in reading of histopathology samples of BE tissues between US and European pathologists.

Liver health in adults with Fontan circulation: A multicenter cross-sectional study

OBJECTIVES

Liver disease is an important contributor to morbidity and mortality in patients after Fontan surgery. There has been no large-scale survey of liver health in this population. We sought to explore the prevalence and predictors of liver disease in a multicenter cohort of adults with Fontan physiology.

METHODS

Subjects were recruited from 6 adult congenital heart centers. Demographics; clinical history; and laboratory, imaging, and histopathology data were obtained.

RESULTS

Of 241 subjects (median age 25.8 years [11.8-59.4], median time since Fontan 20.3 years [5.4-34.5]), more than 94% of those who underwent testing (208 of 221) had at least 1 abnormal liver-related finding. All hepatic imaging (n = 54) and liver histology (n = 68) was abnormal. Subjects with abnormal laboratory values had higher sinusoidal fibrosis stage (2 vs 1, P = .007) and higher portal fibrosis stage (3 vs 1, P = .003) compared with those with all normal values. Low albumin correlated with lower sinusoidal fibrosis stage (1 vs 2; P = .02) and portal fibrosis stage (0 vs 3, P = .002); no other liver studies correlated with fibrosis. Regenerative nodules were seen on 33% of histology specimens.

CONCLUSIONS

Regardless of modality, findings of liver disease are common among adults with Fontan circulation, even those appearing clinically well. Cirrhosis is present in up to one-third of subjects. Correlations between hepatic fibrosis stage and clinical history or findings on noninvasive testing are few. Further research is needed to identify patients at risk for more severe liver disease and to determine the best methods for assessing liver health in this population.

Role of Histologic Inflammation in the Natural History of Ulcerative Colitis

The goals of therapy for ulcerative colitis have moved from symptom improvement to mucosal healing, and finally histologic resolution. The natural history of histologic inflammation in ulcerative colitis progresses from initial cellular infiltration to architectural disruption and recovery on medical therapy. Many studies have linked histologic changes to clinical outcomes, providing prognostic value to histologic abnormalities. This review covers all these components.

In oesophageal squamous cells, nitric oxide causes S-nitrosylation of Akt and blocks SOX2 (sex determining region Y-box 2) expression

OBJECTIVE

Barrett's metaplasia might develop if GORD causes oesophageal squamous cells to convert into columnar cells. Acid and bile exposures upregulate columnar differentiation genes like CDX2 in oesophageal squamous cells, but it is not known if such exposures downregulate squamous differentiation genes like SOX2. In addition to acid and bile, patients with GORD also have high oesophageal concentrations of nitric oxide (NO). This study aims to determine how acid, bile salts and NO affect genes that influence oesophageal cell phenotype.

DESIGN

Oesophageal squamous cells from patients with Barrett's oesophagus were exposed to acidic bile salts or NOC-9 (an NO donor). SOX2, p63 (squamous transcription factor) and CDX2 mRNAs were measured by quantitative RT-PCR. SOX2 and its regulatory Akt pathway proteins were evaluated by western blotting. S-nitrosylation by NO was blocked by dithiothreitol. Immunohistochemistry for SOX2 was performed on the oesophagus of rats with surgically induced GORD which were fed diets with and without nitrite supplementation.

RESULTS

In oesophageal squamous cells, NO profoundly decreased SOX2 protein and caused a significantly greater decrease in SOX2 mRNA than did acidic bile salts. NO also decreased p63 and increased CDX2 expression. NO caused S-nitrosylation of Akt, blocking its phosphorylation. Akt pathway inhibition by LY294002 or Akt siRNA reduced SOX2 mRNA. Rats fed with nitrite-supplemented diets exhibited weaker SOX2 oesophageal staining than rats fed with normal diets.

CONCLUSIONS

In oesophageal squamous cells, NO blocks SOX2 expression through Akt S-nitrosylation. NO also increases CDX2 and decreases p63 expression. By triggering molecular events preventing squamous differentiation while promoting intestinal differentiation, NO might contribute to Barrett's pathogenesis.

Predictive value of biomarkers of hepatic fibrosis in adult Fontan patients

BACKGROUND

Hepatic fibrosis is highly prevalent in individuals with Fontan circulation. FibroSure (LabCorp, Burlington, NC) and hyaluronic acid (HA) have been validated for assessment of hepatic fibrosis in several forms of liver disease. We sought to determine whether these tests could identify Fontan patients with advanced hepatic fibrosis or cirrhosis.

METHODS

Subjects who had liver biopsy and FibroSure or HA testing within 6 months of biopsy were identified from the Alliance for Adult Research in Congenital Cardiology Fontan Liver Health study. Biopsy specimens were scored for degree of sinusoidal and portal fibrosis on a 3- and 5-point scale, respectively. Histologic findings were correlated with FibroSure and HA results.

RESULTS

The study included 27 subjects. Median age was 26.8 years (range, 17.4-59.8 years), and the median time since the Fontan surgery was 20.4 years (range, 12.0-31.3 years). FibroSure scores were elevated (>0.21) in 21 of 23 subjects (91%), and the scores for 3 (13%) suggested cirrhosis (>0.74). HA suggested cirrhosis (>46 ng/mL) in 3 of 17 subjects (18%). One subject died during the collection period. Eleven of 26 subjects (42%) had 4/5 or 5/5 portal fibrosis, consistent with cirrhosis; 17 (63%) had 3/3 sinusoidal fibrosis involving >66% of sinusoids. The FibroSure score and HA levels did not correlate with the degree of hepatic fibrosis and did not predict cirrhosis.

CONCLUSIONS

Abnormal biomarkers of hepatic fibrosis and specimen-proven hepatic fibrosis are common in adults with Fontan circulation. However, FibroSure and HA do not accurately predict the degree of histologic hepatic fibrosis. Further studies are needed to guide strategies for surveillance of liver disease in this population.

Association of Acute Gastroesophageal Reflux Disease With Esophageal Histologic Changes

IMPORTANCE

The histologic changes associated with acute gastroesophageal reflux disease (GERD) have not been studied prospectively in humans. Recent studies in animals have challenged the traditional notion that reflux esophagitis develops when esophageal surface epithelial cells are exposed to lethal chemical injury from refluxed acid.

OBJECTIVE

To evaluate histologic features of esophageal inflammation in acute GERD to study its pathogenesis.

DESIGN, SETTING, AND PARTICIPANTS

Patients from the Dallas Veterans Affairs Medical Center who had reflux esophagitis successfully treated with proton pump inhibitors (PPIs) began 24-hour esophageal pH and impedance monitoring and esophagoscopy (including confocal laser endomicroscopy [CLE]) with biopsies from noneroded areas of distal esophagus at baseline (taking PPIs) and at 1 week and 2 weeks after stopping the PPI medication. Enrollment began May 2013 and follow-up ended July 2015.

INTERVENTIONS

PPIs stopped for 2 weeks.

MAIN OUTCOMES AND MEASURES

Twelve patients (men, 11; mean age, 57.6 year [SD, 13.1]) completed the study. Primary outcome was change in esophageal inflammation 2 weeks after stopping the PPI medication, determined by comparing lymphocyte, eosinophil, and neutrophil infiltrates (each scored on a 0-3 scale) in esophageal biopsies. Also evaluated were changes in epithelial basal cell and papillary hyperplasia, surface erosions, intercellular space width, endoscopic grade of esophagitis, esophageal acid exposure, and mucosal impedance (an index of mucosal integrity).

RESULTS

At 1 week and 2 weeks after discontinuation of PPIs, biopsies showed significant increases in intraepithelial lymphocytes, which were predominantly T cells (median [range]: 0 (0-2) at baseline vs 1 (1-2) at both 1 week [P = .005] and 2 weeks [P = .002]); neutrophils and eosinophils were few or absent. Biopsies also showed widening of intercellular spaces (confirmed by CLE), and basal cell and papillary hyperplasia developed without surface erosions. Two weeks after stopping the PPI medication, esophageal acid exposure increased (median: 1.2% at baseline to 17.8% at 2 weeks; Δ, 16.2% [95% CI, 4.4%-26.5%], P = .005), mucosal impedance decreased (mean: 2671.3 Ω at baseline to 1508.4 Ω at 2 weeks; Δ, 1162.9 Ω [95% CI, 629.9-1695.9], P = .001), and all patients had evidence of esophagitis.

CONCLUSIONS AND RELEVANCE

In this preliminary study of 12 patients with severe reflux esophagitis successfully treated with PPI therapy, stopping PPI medication was associated with T lymphocyte-predominant esophageal inflammation and basal cell and papillary hyperplasia without loss of surface cells. If replicated, these findings suggest that the pathogenesis of reflux esophagitis may be cytokine-mediated rather than the result of chemical injury.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01733810.

Colorectal cancer in Crohn's colitis is comparable to sporadic colorectal cancer

PURPOSE

It is now recognized that Crohn's disease (CD), similar to ulcerative colitis (UC), carries an up to 20-fold higher cancer risk, and the development of colorectal carcinoma (CRC) is a major long-term complication. Once CRC is present, molecular profiling is one of the components in selecting appropriate treatment strategies; however, in contrast to UC, genetic alterations in Crohn's colitis-associated CRC are poorly understood.

METHODS

In a series of 227 patients with Crohn's colitis, we identified 33 cases of CRC (~14 %) and performed targeted mutational analysis of BRAF/KRAS/NRAS and determined microsatellite status as well as immunophenotype of the tumors.

RESULTS

In the CRC cohort, the median age at time of cancer diagnosis was 58 (range 34-77 vs. 59.5 in sporadic; P = 0.81) and the median CD duration was 29 years (range 6-45). As a group, CRC complicating Crohn's colitis is BRAF (97 %) and NRAS (100 %) wild type and the vast majority is microsatellite stable (94 %); KRAS-mutations were found in six cases (18 %). Stage grouping, anatomic distribution, and overall survival were similar to sporadic CRC; however, long-standing CD (≥25 years) as well as gastric-immunophenotype (MUC5AC+) was associated with significantly shorter overall survival (P = 0.0029; P = 0.036, respectively).

CONCLUSION

In summary, the clinicopathological and molecular profile of CD-associated CRC is similar to that observed in sporadic CRC.

Pathology of premalignant colorectal neoplasia

Colorectal cancer is a heterogeneous oncological disease that develops through several molecular pathways. Each pathway is associated with specific neoplastic precursor lesions. Classification of colorectal polyps and the molecular features of associated colorectal cancers have undergone significant changes. An understanding of colorectal carcinogenesis and the molecular features of colorectal carcinomas is now regarded as necessary for personalized treatment and management of patients with colon cancer, and even for patients undergoing screening colonoscopy for early detection and prevention of colorectal cancer. In the present review, we describe the pathological and molecular features of epithelial precursor lesions involved in the early phases of colorectal carcinogenesis.

Paired exome analysis of Barrett's esophagus and adenocarcinoma

Barrett's esophagus is thought to progress to esophageal adenocarcinoma (EAC) through a stepwise progression with loss of CDKN2A followed by TP53 inactivation and aneuploidy. Here we present whole-exome sequencing from 25 pairs of EAC and Barrett's esophagus and from 5 patients whose Barrett's esophagus and tumor were extensively sampled. Our analysis showed that oncogene amplification typically occurred as a late event and that TP53 mutations often occurred early in Barrett's esophagus progression, including in non-dysplastic epithelium. Reanalysis of additional EAC exome data showed that the majority (62.5%) of EACs emerged following genome doubling and that tumors with genomic doubling had different patterns of genomic alterations, with more frequent oncogenic amplification and less frequent inactivation of tumor suppressors, including CDKN2A. These data suggest that many EACs emerge not through the gradual accumulation of tumor-suppressor alterations but rather through a more direct path whereby a TP53-mutant cell undergoes genome doubling, followed by the acquisition of oncogenic amplifications.

Mitochondrial STAT3 contributes to transformation of Barrett's epithelial cells that express oncogenic Ras in a p53-independent fashion

Metaplastic epithelial cells of Barrett's esophagus transformed by the combination of p53-knockdown and oncogenic Ras expression are known to activate signal transducer and activator of transcription 3 (STAT3). When phosphorylated at tyrosine 705 (Tyr705), STAT3 functions as a nuclear transcription factor that can contribute to oncogenesis. STAT3 phosphorylated at serine 727 (Ser727) localizes in mitochondria, but little is known about mitochondrial STAT3's contribution to carcinogenesis in Barrett's esophagus, which is the focus of this study. We introduced a constitutively active variant of human STAT3 (STAT3CA) into the following: 1) non-neoplastic Barrett's (BAR-T) cells; 2) BAR-T cells with p53 knockdown; and 3) BAR-T cells that express oncogenic H-Ras(G12V). STAT3CA transformed only the H-Ras(G12V)-expressing BAR-T cells (evidenced by loss of contact inhibition, formation of colonies in soft agar, and generation of tumors in immunodeficient mice), and did so in a p53-independent fashion. The transformed cells had elevated levels of both mitochondrial (Ser727) and nuclear (Tyr705) phospho-STAT3. Introduction of a STAT3CA construct with a mutated tyrosine phosphorylation site into H-Ras(G12V)-expressing Barrett's cells resulted in high levels of mitochondrial phospho-STAT3 (Ser727) with little or no nuclear phospho-STAT3 (Tyr705), and the cells still formed tumors in immunodeficient mice. Thus tyrosine phosphorylation of STAT3 is not required for tumor formation in Ras-expressing Barrett's cells. We conclude that mitochondrial STAT3 (Ser727) can contribute to oncogenesis in Barrett's cells that express oncogenic Ras. These findings suggest that agents targeting STAT3 might be useful for chemoprevention in patients with Barrett's esophagus.

High Goblet Cell Count Is Inversely Associated with Ploidy Abnormalities and Risk of Adenocarcinoma in Barrett's Esophagus

Purpose

Goblet cells may represent a potentially successful adaptive response to acid and bile by producing a thick mucous barrier that protects against cancer development in Barrett's esophagus (BE). The aim of this study was to determine the relationship between goblet cells (GC) and risk of progression to adenocarcinoma, and DNA content flow cytometric abnormalities, in BE patients.

Experimental Design

Baseline mucosal biopsies (N=2988) from 213 patients, 32 of whom developed cancer during the follow up period, enrolled in a prospective dynamic cohort of BE patients were scored in a blinded fashion, for the total number (#) of GC, mean # of GC/crypt (GC density), # of crypts with ≥ 1 GC, and the proportion of crypts with ≥1 GC, in both dysplastic and non-dysplastic epithelium separately. The relationship between these four GC parameters and DNA content flow cytometric abnormalities and adenocarcinoma outcome was compared, after adjustment for age, gender, and BE segment length.

Results

High GC parameters were inversely associated with DNA content flow cytometric abnormalities, such as aneuploidy, ploidy >2.7N, and an elevated 4N fraction > 6%, and with risk of adenocarcinoma. However, a Kaplan-Meier analysis showed that the total # of GC and the total # crypts with ≥1 GC were the only significant GC parameters (p<0.001 and 0.003, respectively).

Conclusions

The results of this study show, for the first time, an inverse relationship between high GC counts and flow cytometric abnormalities and risk of adenocarcinoma in BE. Further studies are needed to determine if GC depleted foci within esophageal columnar mucosa are more prone to neoplastic progression or whether loss of GC occurs secondary to underlying genetic abnormalities.

Barrett's oesophagus diagnostic criteria: endoscopy and histology

This review summarizes the endoscopic and histologic features of Barrett's oesophagus(BO) as well as some of the recent advancements and controversies. BO represents metaplastic conversion of normal squamous epithelium of tubular oesophagus to columnar epithelium. The diagnosis of BO requires a combination of endoscopic and histopathologic findings. There is worldwide controversy regarding the exact definition of BO, particularly with regard to the requirement to histologically identify goblet cells in biopsies. The presence and detectability of goblet cells might vary depending on a variety of factors and is subject to sampling error. Therefore, a systematic biopsy sampling with sufficient number of biopsies is currently recommended to limit the likelihood of a false negative result for detection of goblet cells. There are both endoscopic and pathologic challenges in evaluating gastro-oesophageal junction biopsies in patients with irregular Z lines to determine the exact location of the sample (i.e., oesophagus versus stomach). Recently, several novel endoscopic techniques have been developed to improve BO detection. However, none have been validated yet in clinical practice. The surveillance of patients with BO relies on histologic evaluation of dysplasia. However, there are significant pathologic limitations and diagnostic variability in evaluating the presence and grading of BO dysplasia, particularly with regard to the more recently recognized non-intestinal types of dysplasia. All BO dysplasia samples should be reviewed by an expert gastrointestinal pathologist to confirm the diagnosis. Finally, it is important to emphasize that close interaction between gastroenterologists and pathologists is essential to ensure proper evaluation of endoscopic biopsies in order to optimize the surveillance and clinical management of patients with BO.

A contemporary and critical appraisal of 'indeterminate colitis'

Distinguishing ulcerative colitis (UC) from Crohn's disease (CD) is normally based on evaluation of a variety of clinical, radiologic, serologic and pathologic findings, the latter in biopsy and/or resection specimens. Unfortunately, some patients with IBD show overlapping pathologic features of UC and CD, which makes definite distinction between these two disorders difficult or even impossible. In most instances of uncertainty, the patient shows clinical and pathologic features of UC, but in addition, the patient's colon resection specimen reveals one or more CD-like features. In this setting, a diagnosis of indeterminate colitis (IC) is often rendered. IC is not a distinct disease entity, and, thus, it has no diagnostic criteria. The most common causes of uncertainty in IBD pathology that may lead to a diagnosis of IC in a colon resection specimen includes the presence of fulminant (severe and toxic) colitis, insufficient radiologic, endoscopic, or pathologic information (including analysis of prior biopsies) on the patient, failure to utilize major diagnostic criteria as hard evidence in favor of CD, failure to recognize unusual variants of UC and CD that may mimic each other, failure to recognize non-IBD mimics and other superimposed diseases that cause unusual pathologic features in a resection specimen, an attempt to distinguish UC from CD in mucosal biopsies of the colon and ileum, or an attempt to change the patients diagnosis (of UC or CD) based on pouch or diversion-related complications. Details of each of these causes of uncertainty are discussed, in detail, in this review article. A diagnosis of IC should never be made clinically or by pathologists based on evaluation of pre-resection colonic mucosal biopsies. Ultimately, the majority of indeterminate cases represent UC, and, thus, most of these patient can be treated safely with a colectomy combined with an ileal pouch anal anastomosis procedure.

Morphology and natural history of familial adenomatous polyposis-associated dysplastic fundic gland polyps

AIMS

Most patients with familial adenomatous polyposis (FAP) develop gastric fundic gland polyps, with many displaying low-grade dysplasia. This study evaluates the natural history and morphological phenotype of dysplasia in FAP-associated fundic gland polyps.

METHODS AND RESULTS

Patients with FAP and dysplastic fundic gland polyps (n = 24) were identified. Twenty-two of 24 FAP-associated dysplastic fundic gland polyps showed a gastric phenotype and two had mixed phenotype. During a mean 6.1-year follow-up (range 0.8-12.6 years) and 5.7 endoscopies (range 2-22), one patient (4%) was diagnosed with a fundic gland polyp with high-grade dysplasia, while 23 patients (96%) in this cohort had either no dysplasia or persistent low-grade dysplasia. Contemporary patients with sporadic fundic gland polyps with low-grade dyplasia had similar morphology and outcomes to the FAP-associated fundic gland polyp cohort. Dysplasia in fundic gland polyps (FAP-associated and sporadic) was associated less frequently with intestinal phenotype, high-grade dysplasia and the finding of concurrent or subsequent carcinoma compared to contemporary patients with sporadic gastric dysplasia not occurring in fundic gland polyps.

CONCLUSIONS

This cohort of patients with FAP-associated dysplastic fundic gland polyps rarely developed high-grade dysplasia and gastric adenocarcinoma was absent.

Pseudo-buried Barrett's post radiofrequency ablation for Barrett's esophagus, with or without prior endoscopic resection

BACKGROUND AND STUDY AIM

In our experience, biopsies from small residual islands of nonburied Barrett's mucosa after radiofrequency ablation (RFA) are occasionally reported by pathologists to contain "buried Barrett's" upon histological evaluation, despite the fact that these islands of columnar mucosa were visible endoscopically. The aim of this study was to evaluate the frequency of buried Barrett's in biopsies obtained from small residual Barrett's islands ( < 5 mm) sampled post-RFA, compared with biopsies from normal neosquamous epithelium.

PATIENTS AND METHODS

Biopsies obtained from normal-appearing neosquamous epithelium and from small Barrett's islands ( < 5 mm) in 69 consecutive Barrett's patients treated with RFA were evaluated for the presence of buried columnar mucosa.

RESULTS

A total of 2515 biopsies were obtained from neosquamous epithelium during follow-up post-RFA. Buried glands were found in 0.1 % of biopsies from endoscopically normal neosquamous epithelium. However, when small islands of columnar mucosa were biopsied, buried glands were detected in 21 % of biopsies.

CONCLUSION

To avoid accidental sampling of small islands resulting in a false-positive histological diagnosis of buried Barrett's, thorough inspection should be performed before obtaining biopsies during post-RFA follow-up.

Neonatal Fc receptor expression in dendritic cells mediates protective immunity against colorectal cancer

Cancers arising in mucosal tissues account for a disproportionately large fraction of malignancies. Immunoglobulin G (IgG) and the neonatal Fc receptor for IgG (FcRn) have an important function in the mucosal immune system that we have now shown extends to the induction of CD8(+) T cell-mediated antitumor immunity. We demonstrate that FcRn within dendritic cells (DCs) was critical for homeostatic activation of mucosal CD8(+) T cells that drove protection against the development of colorectal cancers and lung metastases. FcRn-mediated tumor protection was driven by DCs activation of endogenous tumor-reactive CD8(+) T cells via the cross-presentation of IgG complexed antigens (IgG IC), as well as the induction of cytotoxicity-promoting cytokine secretion, particularly interleukin-12, both of which were independently triggered by the FcRn-IgG IC interaction in murine and human DCs. FcRn thus has a primary role within mucosal tissues in activating local immune responses that are critical for priming efficient anti-tumor immunosurveillance.

Temporal and spatial evolution of somatic chromosomal alterations: a case-cohort study of Barrett's esophagus

All cancers are believed to arise by dynamic, stochastic somatic genomic evolution with genome instability, generation of diversity, and selection of genomic alterations that underlie multistage progression to cancer. Advanced esophageal adenocarcinomas have high levels of somatic copy number alterations. Barrett's esophagus is a risk factor for developing esophageal adenocarcinoma, and somatic chromosomal alterations (SCA) are known to occur in Barrett's esophagus. The vast majority (∼95%) of individuals with Barrett's esophagus do not progress to esophageal adenocarcinoma during their lifetimes, but a small subset develop esophageal adenocarcinoma, many of which arise rapidly even in carefully monitored patients without visible endoscopic abnormalities at the index endoscopy. Using a well-designed, longitudinal case-cohort study, we characterized SCA as assessed by single-nucleotide polymorphism arrays over space and time in 79 "progressors" with Barrett's esophagus as they approach the diagnosis of cancer and 169 "nonprogressors" with Barrett's esophagus who did not progress to esophageal adenocarcinoma over more than 20,425 person-months of follow-up. The genomes of nonprogressors typically had small localized deletions involving fragile sites and 9p loss/copy neutral LOH that generate little genetic diversity and remained relatively stable over prolonged follow-up. As progressors approach the diagnosis of cancer, their genomes developed chromosome instability with initial gains and losses, genomic diversity, and selection of SCAs followed by catastrophic genome doublings. Our results support a model of differential disease dynamics in which nonprogressor genomes largely remain stable over prolonged periods, whereas progressor genomes evolve significantly increased SCA and diversity within four years of esophageal adenocarcinoma diagnosis, suggesting a window of opportunity for early detection.

Crypt dysplasia in Barrett's oesophagus shows clonal identity between crypt and surface cells

Epithelial dysplasia is an important histological diagnosis signifying the presence of pre-invasive disease, usually needing intervention. However, the specific genetic changes responsible for the induction of this phenotypic change are unknown. Moreover, recent reports indicate that the dysplastic phenotype may not be immutable: in basal crypt dysplasia (CD), unequivocal dysplastic changes are seen in the crypts in Barrett's oesophagus and other pre-invasive lesions in the gastrointestinal tract, but the upper crypts and surface epithelium associated with these dysplastic crypts show the definitive morphology of a differentiated epithelium. The genotypic relationship between CD and the differentiated surface epithelium is presently unclear. We obtained 17 examples of CD: the lower and upper crypts and surface epithelium were differentially laser-microdissected from formalin-fixed, paraffin-embedded sections and mutations were sought in tumour suppressor genes frequently associated with progression in Barrett's oesophagus. We found two patients who both showed a c. C238T mutation in the CDKN2A (CDKN2AInk4A) gene and where the precise microanatomical relationships could be discerned: this mutation was present in both the CD at the crypt base and in the upper crypt and surface epithelium. We conclude that, in CD, the dysplastic basal crypt epithelium and the upper crypt and surface epithelium show clonal CDKN2A mutations, thus showing definitively that the surface epithelium is derived from the dysplastic crypt epithelium: the dysplastic phenotype is therefore not fixed and can be reversed. The mechanism of this change is unclear but may be related to the possibility that dysplastic cells can, probably early in their progression, respond to differentiation signals. However, it is also clear that a heavy mutational burden can be borne by crypts in the gastrointestinal tract without the development of phenotypic dysplasia. We are evidently some way from understanding the plasticity and the genotypic correlates of the dysplastic phenotype.