Quality control in diagnostic immunohistochemistry: integrated on-slide positive controls.

Standardization in immunohistochemistry is a priority in modern pathology and requires strict quality control. Cost containment has also become fundamental and auditing of all procedures must take into account both these principles. Positive controls must be routinely performed so that their positivity guarantees the appropriateness of the immunohistochemical procedure. The aim of this study is to develop a low cost (utilizing a punch biopsy-PB-tool) procedure to construct positive controls which can be integrated in the patient's tissue slide. Sixteen frequently used control blocks were selected and multiple cylindrical samples were obtained using a 5-mm diameter punch biopsy tool, separately re-embedding them in single blocks. For each diagnostic immunoreaction requiring a positive control, an integrated PB-control section (cut from the appropriate PB-control block) was added to the top right corner of the diagnostic slide before immunostaining. This integrated control technique permitted a saving of 4.75% in total direct lab costs and proved to be technically feasible and reliable. Our proposal is easy to perform and within the reach of all pathology labs, requires easily available tools, its application costs is less than using external paired controls and ensures that a specific control for each slide is always available.

The dynamics of the oesophageal squamous epithelium 'normalisation' process in patients with gastro-oesophageal reflux disease treated with long-term acid suppression or anti-reflux surgery.

BACKGROUND: Proton pump inhibitors and laparoscopic anti-reflux surgery (LARS) offer long-term symptom control to patients with gastro-oesophageal reflux disease (GERD). AIM: To evaluate the process of 'normalisation' of the squamous epithelium morphology of the distal oesophagus on these therapies. METHODS: In the LOTUS trial, 554 patients with chronic GERD were randomised to receive either esomeprazole (20-40 mg daily) or LARS. After 5 years, 372 patients remained in the study (esomeprazole, 192; LARS, 180). Biopsies were taken at the Z-line and 2 cm above, at baseline, 1, 3 and 5 years. A severity score was calculated based on: papillae elongation, basal cell hyperplasia, intercellular space dilatations and eosinophilic infiltration. The epithelial proliferative activity was assessed by Ki-67 immunohistochemistry. RESULTS: A gradual improvement in all variables over 5 years was noted in both groups, at both the Z-line and 2 cm above. The severity score decreased from baseline at each subsequent time point in both groups (P < 0.001, all comparisons), attaining a normal level by 5 years. Corresponding decreases in Ki-67 expression were observed (P < 0.001, all comparisons). No significant differences were found between esomeprazole treatment and LARS. Neither baseline severity score nor Ki-67 expression predicted the risk of treatment failure. CONCLUSIONS: Five years of treatment is generally required before squamous epithelial cell morphology and proliferation are 'normalised' in patients with chronic GERD, despite endoscopic and symptomatic disease control. Control of the acid component of the refluxate seems to play the predominant role in restoring tissue morphology.

Long-term safety of proton pump inhibitor therapy assessed under controlled, randomised clinical trial conditions: data from the SOPRAN and LOTUS studies.

BACKGROUND: Control of chronic gastro-oesophageal reflux disease may be achieved either by anti-reflux surgery (ARS) or by long-term medical therapy with proton pump inhibitors (PPIs). The primary efficacy results of the SOPRAN study, comparing long-term omeprazole use with open ARS, and the LOTUS study, comparing long-term esomeprazole use with laparoscopic ARS, have been reported. A secondary objective of these studies was to address the long-term safety of these respective therapeutic strategies and thereby provide a valid scientific platform for assessing long-term PPI safety. AIM: To assess the safety of long-term PPI therapy with omeprazole and esomeprazole through analyses of data from the randomised SOPRAN and LOTUS studies. METHODS: Safety data were collected from patients during the 12-year period of the SOPRAN study (n = 298) and the 5-year period of the LOTUS study (n = 514). Reported serious adverse events (SAEs) and changes in laboratory variables were analysed. RESULTS: Across both studies, SAEs were reported at a similar frequency in the PPI and ARS treatment groups. Taking the time frames into consideration, the number of fatal SAEs in the two studies was low in both treatment groups. Laboratory results, including routine haematology and tests for liver enzymes, electrolytes, vitamin D, vitamin B12 , folate and homocysteine, showed no clinically relevant changes over time. As expected, gastrin and chromogranin A were elevated in the PPI groups, with the greatest increases observed in the first year. CONCLUSION: No major safety concerns arose during 5-12 years of continuous PPI therapy. (ClinicalTrials.gov: NCT00251927 and NCT00256737).

Helicobacter pylori HP(2-20) induces eosinophil activation and accumulation in superficial gastric mucosa and stimulates VEGF-alpha and TGF-beta release by interacting with formyl-peptide receptors.

Eosinophils participate in the immune response against Helicobacter pylori, but little is known about their role in the gastritis associated to the infection. We recently demonstrated that the Hp(2-20) peptide derived from H. pylori accelerates wound healing of gastric mucosa by interacting with N-formyl peptide receptors (FPRs) expressed on gastric epithelial cells. The aim of the present study was to investigate whether eosinophils play a role in the repair of gastric mucosa tissue during H. pylori infection. Immuno-histochemistry and transmission electron microscopy were used to detect eosinophils in gastric mucosal biopsies. Eosinophil re-distribution occurred in the gastric mucosa of H. pylori-infected patients: their density did not change in the deep mucosal layer, whereas it increased in the superficial lamina propria just below the foveolar epithelium; eosinophils entered the epithelium itself as well as the lumen of foveolae located close to the area harboring bacteria, which in turn were also engulfed by eosinophils. The H. pylori-derived peptide Hp(2-20) stimulated eosinophil migration through the engagement of FPR2 and FPR3, and also induced production of VEGF-A and TGF-beta, two key mediators of tissue remodelling. We also demonstrate that Hp(2-20) in vivo induced eosinophil infiltration in rat gastric mucosa after injury brought about by indomethacin. This study suggests that eosinophil infiltrate could modulate the capacity of gastric mucosa to maintain or recover its integrity thereby shedding light on the role of eosinophils in H. pylori infection.

Molecular characterization of an Italian series of sporadic GISTs.

PURPOSE: Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors of the gastrointestinal tract. Most (80 %) contain activating mutations in the KIT receptor tyrosine kinase, roughly 10 % in platelet-derived growth factor receptor-alpha (PDGFRA). In a small subset, BRAF mutations are an alternative molecular pathway. GISTs respond well to imatinib, but low response is seen in patients with wild-type KIT or PDGFRA. Resistance has also been reported as a result of mutations in downstream effectors such as BRAF. METHODS: We provide here a molecular characterization of a series of primary GISTs from Italian patients. Of 121 GIST cases diagnosed between 2000 and 2012, 83 were evaluated by PCR amplification and direct sequencing for mutations in KIT exons 8, 9, 11, 13, and 17, PDGFRA exons 12, 14, and 18, and BRAF exon 15. Eighty-one GISTs also underwent K-RAS testing. RESULTS: Sixty-four GISTs were positive: 55 had mutations in KIT and 9 in PDGFRA; 16 patients were mutation negative. Three samples came from NF1 patients and were KIT- and PDGFRA negative. Overall, we identified six novel mutations in KIT (p.K550_M552delinsL, p.Q556_W557delinsG p.Q556_G575del, p.W557_V559delinsQ p.P573_R588dup, p.G592_K593dup) and one novel mutation in PDGFRA (p.D842_N848delinsVDV), thus contributing to widening the spectrum of known mutations in GIST tumors and confirming the most frequently altered regions underlying GIST development. CONCLUSIONS: Among the 64 KIT- and PDGFRA-positive sporadic patients in our series, no BRAF or KRAS mutations were identified, suggesting that co-occurrence of these mutations is likely to be rare in the northwestern Italian population and not a frequent cause of primary resistance to imatinib in KIT-positive GIST patients.

Gastric exocrine and endocrine cell morphology under prolonged acid inhibition therapy: results of a 5-year follow-up in the LOTUS trial.

BACKGROUND: Sustained acid inhibition with PPI stimulates gastrin secretion, exerting a proliferative drive on enterochromaffin-like cells (ECL cells) of the oxyntic mucosa. It may also accelerate development of gastric gland atrophy in Helicobacter pylori-infected individuals. AIMS: To evaluate gastric exocrine and endocrine cell changes in GERD patients randomised to laparoscopic antireflux surgery (LARS, n = 288) or long-term (5 years) esomeprazole (ESO) treatment (n = 266). METHODS: Antral and corpus biopsies were taken at endoscopy and serum gastrin and chromogranin A levels were assayed, at baseline and after 1, 3 and 5 years' therapy. RESULTS: Biopsies were available at each time point for 158 LARS patients and 180 ESO patients. In H. pylori-infected subjects, antral mucosal inflammation and activity improved significantly (P < 0.001) and stabilised after 3 years on esomeprazole while no change in inflammation was observed after LARS. Oxyntic mucosal inflammation and activity remained stable on esomeprazole but decreased slightly over time after LARS. Neither intestinal metaplasia nor atrophy developed in the oxyntic mucosa. ECL cell density increased significantly after ESO (P < 0.001), corresponding with an increase in circulating gastrin and chromogranin A. After LARS, there was a significant decrease in ECL cell density (P < 0.05), accompanied by a marginal decrease in gastrin and chromogranin. CONCLUSIONS: Antral gastritis improved in H. pylori-infected GERD patients after 5 years on esomeprazole, with little change in laparoscopic antireflux surgery patients, who acted as a control. Despite a continued proliferative drive on enterochromaffin-like cells during esomeprazole treatment, no dysplastic or neoplastic lesions were found and no safety concerns were raised. NCT 00251927.

Medical or surgical management of GERD patients with Barrett's esophagus: the LOTUS trial 3-year experience.

INTRODUCTION: The long-term management of gastroesophageal reflux in patients with Barrett's esophagus (BE) is not well supported by an evidence-based consensus. We compare treatment outcome in patients with and without BE submitted to standardized laparoscopic antireflux surgery (LARS) or esomeprazole treatment. METHODS: In the Long-Term Usage of Acid Suppression Versus Antireflux Surgery trial (a European multicenter randomized study), LARS was compared with dose-adjusted esomeprazole (20-40 mg daily). Operative difficulty, complications, symptom outcomes [Gastrointestinal Symptom Rating Scale (GSRS) and Quality of Life in Reflux and Dyspepsia (QOLRAD)], and treatment failure at 3 years and pH testing (after 6 months) are reported. RESULTS: Of 554 patients with gastroesophageal reflux disease, 60 had BE-28 randomized to esomeprazole and 32 to LARS. Very few BE patients on either treatment strategy (four of 60) experienced treatment failure during the 3-year follow-up. Esophageal pH in BE patients was significantly better controlled after surgical treatment than after esomeprazole (p = 0.002), although mean GSRS and QOLRAD scores were similar for the two therapies at baseline and at 3 years. Although operative difficulty was slightly greater in patients with BE than those without, there was no difference in postoperative complications or level of symptomatic reflux control. CONCLUSION: In a well-controlled surgical environment, the success of LARS is similar in patients with or without BE and matches optimized medical therapy.

Comparing laparoscopic antireflux surgery with esomeprazole in the management of patients with chronic gastro-oesophageal reflux disease: a 3-year interim analysis of the LOTUS trial.

BACKGROUND: With the introduction of laparoscopic antireflux surgery (LARS) for gastro-oesophageal reflux disease (GORD) along with the increasing efficacy of modern medical treatment, a direct comparison is warranted. The 3-year interim results of a randomised study comparing both the efficacy and safety of LARS and esomeprazole (ESO) are reported. METHODS: LOTUS is an open, parallel-group multicentre, randomised and controlled trial conducted in dedicated centres in 11 European countries. LARS was completed according to a standardised protocol, comprising a total fundoplication and a crural repair. Medical treatment comprised ESO 20 mg once daily, which could be increased stepwise to 40 mg once daily and then 20 mg twice daily in the case of incomplete GORD control. The primary outcome variable was time to treatment failure (Kaplan-Meier analysis). Treatment failure was defined on the basis of symptomatic relapse requiring treatment beyond that stated in the protocol. RESULTS: 554 patients were randomised, of whom 288 were allocated to LARS and 266 to ESO. The two study arms were well matched. The proportions of patients who remained in remission after 3 years were similar for the two therapies: 90% of surgical patients compared with 93% medically treated for the intention to treat population, p = 0.25 (90% vs 95% per protocol). No major unexpected postoperative complications were experienced and ESO was well tolerated. However, postfundoplication complaints remain a problem after LARS. CONCLUSIONS: Over the first 3 years of this long-term study, both laparoscopic total fundoplication and continuous ESO treatment were similarly effective and well-tolerated therapeutic strategies for providing effective control of GORD.

Gastro-oesophageal reflux symptoms, oesophagitis and Barrett's oesophagus in the general population: the Loiano-Monghidoro study.

OBJECTIVE: Existing endoscopy-based data on gastro-oesophageal reflux disease (GORD) in the general population are scarce. This study aimed to evaluate typical symptoms and complications of GORD, and their associated risk factors, in a representative sample of the Italian population. METHODS: 1533 adults from two Italian villages were approached to undergo symptom assessment using a validated questionnaire and upper gastrointestinal endoscopy. Data were obtained from 1033 individuals (67.4% response rate). RESULTS: The prevalence of reflux symptoms was 44.3%; 23.7% of the population experienced such symptoms on at least 2 days per week (frequent symptoms). The prevalence rates of oesophagitis and Barrett's oesophagus in the population were 11.8% and 1.3%, respectively. Both frequent (relative risk (RR) 2.6; 95% confidence interval (CI) 1.7 to 3.9) and infrequent (RR 1.9; 95% CI 1.2 to 3.0) reflux symptoms were associated with the presence of oesophagitis. No reflux symptoms were reported by 32.8% of individuals with oesophagitis and 46.2% of those with Barrett's oesophagus. Hiatus hernia was associated with frequent reflux symptoms and oesophagitis, and was present in 76.9% of those with Barrett's oesophagus. We found no association between body mass index and reflux symptoms or oesophagitis. CONCLUSIONS: GORD is common in Italy, but the prevalence of Barrett's oesophagus in the community is lower than has been reported in selected populations. Both frequent and infrequent reflux symptoms are associated with an increased risk of oesophagitis. Individuals with oesophagitis and Barrett's oesophagus often have no reflux symptoms.

OLGA staging for gastritis: a tutorial.

Atrophic gastritis (resulting mainly from long-standing Helicobacter pylori infection) is a major risk factor for (intestinal-type) gastric cancer development and the extent/topography of the atrophic changes significantly correlates with the degree of cancer risk. The current format for histology reporting in cases of gastritis fails to establish an immediate link between gastritis phenotype and risk of malignancy. The histology report consequently does not give clinical practitioners and gastroenterologists an explicit message of use in orienting an individual patient's clinical management. Building on current knowledge of the biology of gastritis and incorporating experience gained worldwide by applying the Sydney System for more than 15 years, an international group of pathologists (Operative Link for Gastritis Assessment) has proposed a system for reporting gastritis in terms of stage (the OLGA staging system). Gastritis staging arranges the histological phenotypes of gastritis along a scale of progressively increasing gastric cancer risk, from the lowest (stage 0) to the highest (stage IV). This tutorial aims to provide unequivocal information on how to consistently apply the OLGA staging system in routine diagnostic histology practice.

The impact of biopsy number and site on the accuracy of intestinal metaplasia detection in the stomach A morphometric study based on virtual biopsies.

BACKGROUND: Intestinal metaplasia is a risk factor for gastric carcinoma. So far few studies have focused on the efficacy of endoscopic biopsies in detecting intestinal metaplasia in relation with the site and number of biopsies performed. The present study is aimed to assess the efficacy of single and multiple gastric biopsies in the detection and staging of intestinal metaplasia. MATERIAL AND METHODS: The study was conducted on 455 gastrectomies. We defined the extent of intestinal metaplasia on surgical specimens sampled by the "Swiss roll" technique and assessed the efficiency of an increasing number of "virtual" biopsies performed on the same rolls in recognising the true extent of intestinal metaplasia in the antro-angular region. RESULTS: Seventy-four out of 455 cases showed intestinal metaplasia in more than 5% of the antro-angular mucosa. The correlation between antro-angular intestinal metaplasia on rolls and on virtual biopsies was always highly significant, both when a single biopsy was considered and when groups of multiple biopsies (from 2 to 6 samples) were taken into account (por=20% and intestinal metaplasia <20% groups (p<0.0001). The highest value of concordance between intestinal metaplasia extent in virtual biopsies and in rolls was recorded for a set of 4 antral+1 angular biopsies whereas a set of 2 antral+1 angular biopsies turned out to be the most effective in terms of number/efficacy. CONCLUSIONS: A three biopsy set (2 antral+1 angular) allows correct detection of intestinal metaplasia extent in 90% of cases.

Cell proliferation of squamous epithelium in gastro-oesophageal reflux disease: correlations with clinical, endoscopic and morphological data.

BACKGROUND: The microscopic assessment of squamous epithelium lesions in gastro-oesophageal reflux disease (GERD) is subjective. The Ki67 nuclear antigen expressed by proliferating cells provides an objective measure of regeneration in the squamous epithelium. AIM: To evaluate Ki67 expression in GERD patients and controls, in comparison with histological lesions, pH-metry and endoscopic data. METHODS: Eighty-seven patients with GERD symptoms and 20 symptom-free controls underwent endoscopy and 24-h pH monitoring. Oesophageal biopsies (4 cm, 2 cm and Z-line) were stained with Ki67/MIB-1 antibodies; the Ki67-positive nuclear area was assessed with an image analysis system and expressed as percentage of the whole epithelial area (Ki67-%). RESULTS: Ki67-% was significantly higher in 32 patients with erosive oesophagitis, 44 endoscopy-negative GERD and 11 patients with functional heartburn than in controls (P = 0.0001). Both controls and patients showed a progressive increase in Ki67-% from 4 cm to the Z-line (P < 0.0001). Ki67-% showed a significant correlation with other conventional histological lesions (P ranged between 0.0151 and <0.0001). CONCLUSIONS: Ki67 evaluation provides quantitative and objective data on squamous epithelium proliferative activity. This marker can be applied in the distinction of endoscopy-negative GERD from healthy controls.

Non-antigen-specific CD8(+) T suppressor lymphocytes in diseases characterized by chronic immune responses and inflammation.

Recent studies on regulatory lymphocytes demonstrate that CD8(+) T suppressor (Ts) cells may have great relevance in controlling immune system homeostasis and avoiding development of chronic inflammatory diseases. Among the three subpopulations of CD8(+) Ts cells so far recognized in humans, the type 2 (non-antigen-specific) cell is characterized by the capacity to inhibit both T cell proliferation and cytotoxic T lymphocyte activity through secretion of soluble factors. Previous work has shown the impairment of in vitro generation of type 2 CD8(+) Ts cells from the peripheral blood of relapsed patients with multiple sclerosis, systemic lupus erythematosus, or systemic sclerosis. Here, similar findings are demonstrated for patients with human immunodeficiency virus or chronic hepatitis C virus infection. Furthermore, the presence of type 2 CD8(+) Ts cells infiltrating diseased tissues in patients with autoimmune thyroiditis or cancer is shown. Collectively, these findings suggest that type 2 CD8(+) Ts cells may be involved in the control of pathologic chronic immune responses, contributing in some cases to the pathogenesis of the disease.

Radial distribution of dilated intercellular spaces of the esophageal squamous epithelium in patients with reflux disease exhibiting discrete endoscopic lesions.

INTRODUCTION: Dilatation of intercellular spaces of the esophageal squamous epithelium has been suggested as a marker of early acid reflux-induced damage. This change is a potentially useful addition to histomorphological changes that represent so called minimal endoscopic lesions. We have assessed dilatation of intercellular spaces with regard to: (1) interobserver variability, and (2) whether the incidence of this varies between 'red streaks' and the adjacent normal looking squamous epithelium. METHODS: Esophageal biopsies from 44 patients with chronic gastro-esophageal reflux (GERD) were evaluated. At endoscopy, these patients had one or more red streaks on the tops of the mucosal folds in the distal esophagus. Biopsies were taken from the red streaks and from the normal-appearing mucosa 1 cm lateral to the red streaks. Biopsies were assessed in a blinded fashion by two independent pathologists (MV & RF). Criteria for assessing intercellular space dilatation were evaluated and agreed on prior to the study. RESULTS: Good interobserver agreement was recorded (kappa = 0.82 at the streaks and 0.77 for the control tissues) for absence/presence of intercellular space dilatation. Red streak and control biopsies differed significantly (p = 0.0001), with respect to presence of dilated intercellular spaces, with 90.5 % of the former demonstrating this as present compared to 56.1% in the controls. CONCLUSION: This study supports the concept that esophageal mucosal minimal changes due to reflux is localised and that dilatation of intercellular spaces is an early sign of reflux-induced epithelial damage. The low interobserver variability in the assessment of intercellular space dilatation suggests that this may be a useful variable for assessment of early signs of acid-reflux induced damage to the squamous epithelium of the esophagus by use of light microscopy.

Carditis in patients with gastro-oesophageal reflux disease: results of a controlled study based on both endoscopy and 24-h oesophageal pH monitoring.

BACKGROUND: There are conflicting reports on the role of gastro-oesophageal reflux disease (GERD) and Helicobacter pylori infection in the aetiology of carditis. AIM: The role of reflux and H. pylori infection in causing carditis was assessed in 113 consecutive patients with GERD and in 25 controls. METHODS: All subjects underwent endoscopy and pH test and carditis was diagnosed on biopsies taken across the squamocolumnar junction. Helicobacter pylori was assessed by histology and rapid urease test. GERD was diagnosed by endoscopic oesophagitis or abnormal pH test. RESULTS: Carditis was detected in 53 of 71 GERD patients and in 15 of 20 controls. Among patients, 18 showed absent, 39 mild and 14 marked cardia inflammation and their H. pylori infection rates were 17, 23 and 57%, respectively (P < 0.025). Most patients with carditis (68%) lacked H. pylori infection. pH-metry was abnormal in 15 of 18 patients with normal cardia, 33 of 39 with mild carditis and 12 of 14 with marked inflammation. CONCLUSIONS: Carditis is a frequent finding in GERD and controls. Mild, non-active carditis is frequent in GERD patients. Marked inflammation is associated with both H. pylori and abnormal pH testing. Thus, both GERD and H. pylori infection may play a role in inducing carditis.

Spontaneous transgenesis of human B lymphocytes.

DNA can cross the cell membrane by natural means, but the functional relevance of this phenomenon has not been fully elucidated. Here, we analyzed spontaneous transgenesis of human B cells using plasmid DNA coding for a functional immunoglobulin (Ig) heavy chain gene under the control of a B-cell-specific promoter. Using polymerase chain reaction (PCR), reverse transcriptase-PCR, and flow cytometry in combination, spontaneous transgenesis was documented in Burkitt's lymphoma cell lines, Epstein-Barr virus-transformed cell lines, and peripheral blood B lymphocytes of the mature naïve phenotype (IgM(+)/IgD(+)/CD27(-)). By immunoelectron microscopy, the internalized DNA was seen in the lysosomes/late endosomes and in the cytosol proximal to the nucleus. Importantly, spontaneously transgenic B cells processed and presented to major histocompatibility complex (MHC)-restricted T lymphocytes a peptide expressed in the transgenic product. This is the first demonstration that primary B lymphocytes possess a program for the spontaneous internalization of DNA, which in turn imparts the cell with new immunological functions. As spontaneous transgenesis is obtained using a nonviral vector, does not require prior cell activation, and is not associated with chromosomal integration, the findings reported here open new possibilities for genetic manipulations of mature naïve B lymphocytes for therapy and vaccination.

Malignant adenoma: diagnosis, staging, risk factors, lymph node involvement and problems of sampling.

Colorectal adenoma containing invasive carcinoma corresponds to a carcinoma invading the submucosa and represents the earliest form of clinically relevant colon cancer. Despite the generally favourable course after endoscopic removal, a limited risk of developing lymph node metastases still exists and the correct histologic assessment of malignant polyps can help in defining the evolutive potential. At present, histopathologic parameters alone determine whether a high (35%) or low (7%) risk of nodal metastases exists and the most relevant diagnostic criteria are the grade of differentiation of invasive adenocarcinoma, vascular invasion, the level of invasion of carcinomatous cells and the status of the resection margin.