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The Italian Group of Gastrointestinal Pathologists has named a committee to develop recommendations concerning the surgical pathology report for pancreatic cancer. The committee, formed by individuals with special expertise, wrote the recommendations, which were reviewed and approved by council of the Group. The recommendations are divided into several areas including an informative gross description, gross specimen handling, histopathologic diagnosis, immunohistochemistry, molecular findings, and a checklist. The purpose of these recommendations is to provide a fully informative report for the clinician., (Copyright © 2011 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd.. All rights reserved.)

Reduced-intensity conditioning regimens have reshaped the clinical presentation of graft-versus-host disease after hematopoietic stem cell transplants. However, histopathologic features of graft-versus-host disease following reduced-intensity conditioning regimens have not been fully characterized. In a series of 112 biopsies (skin, n = 60; gastrointestinal [GI] tract, n = 44; liver, n = 8), we described the morphologic profile of graft-versus-host disease following reduced-intensity conditioning and investigated whether histopathologic changes of graft-versus-host disease following reduced-intensity conditioning have a diagnostic and/or prognostic value. Forty-four patients (49.5%) experienced acute graft-versus-host disease, 2 (2.2%) late-onset acute graft-versus-host disease (grade I, n = 13; grade II-IV, n = 33), 24 (27.0%) chronic graft-versus-host disease (de novo n = 12, progressive n = 12) and 19 (21.3%) overlap syndrome. In the skin, we observed: (i) phase-nonspecific changes, such as acute graft-versus-host disease features in chronic graft-versus-host disease patients (n = 4/24; 16.6%), (ii) subtle alterations such as superficial fibrosis in widened dermal papillae (n = 8), in acute graft-versus-host disease/late-onset graft-versus-host disease (n = 6/46; 13.0%) or chronic graft-versus-host disease (n = 2/24, 8.3%) patients, and (iii) features of chronic and acute graft-versus-host disease coexisting in the same specimen in overlap syndrome (n = 3/19; 15.7%). In the GI tract, we did not demonstrate peculiar features differing from those commonly observed in the myeloablative setting. By univariate analysis, a reduced overall survival was associated with graft-versus-host disease type (chronic graft-versus-host disease P = .006, acute graft-versus-host disease P = .03), older age (P = .04), and histopathologic diagnosis of "consistent with" + definite graft-versus-host disease (P = .02). Histopathologic diagnosis retained an independent prognostic value by multivariate analysis (P = .01). The present study indicates that pathologists should be aware of the peculiar morphologic changes of cutaneous graft-versus-host disease following reduced-intensity conditioning and further recommends histopathology in the diagnostic workup of graft-versus-host disease in patients undergoing reduced-intensity conditioning regimen., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Molecular therapies targeting HER2 are part of the established drug armamentarium in breast carcinoma. Now the ToGA trial, an international multicenter phase III clinical study, involving 24 countries globally, has shown that the anti-HER2 humanized monoclonal antibody Trastuzumab is effective in prolonging survival in HER2-positive carcinoma of the stomach and the gastroesophageal junction (GEJ). Similarly to breast carcinoma, >20% of gastric cancers show HER2 overexpression and/or amplification, and this percentage increases to 33% in GEJ tumors. Thus, as in breast carcinoma, pathologists are now asked to evaluate HER2 status in gastric carcinoma samples. As validated in the ToGA trial, the HER2 testing criteria that must be used in evaluating both gastric carcinoma biopsies and surgical specimens significantly differ from those routinely applied in breast carcinoma. The main variations with regard to the pattern of reactivity in HER2-expressing cells are as follows: the completeness of membrane staining is not a "conditio sine qua non" and the number of stained cells necessary to consider a case as positive is different. We must also take note of the much more frequent heterogeneity of HER2 positivity in gastric cancer compared with breast carcinoma and the less stringent correlation between HER2 amplification and protein overexpression that is observed in gastric carcinoma, where more than 20% of cases may carry HER2 amplification, although of low level, without HER2 expression. In these patients, in the ToGA trial, there was no apparent benefit from adding Trastuzumab to chemotherapy: for this reason the European Medicines Agency, while approving usage of Trastuzumab for metastatic adenocarcinoma treatment, indicated HER2 testing by immunohistochemistry as first evaluation assay, followed by fluorescence in situ hybridization in 2+ equivocal cases. HER2 testing in gastric carcinoma is a new field, opening several opportunities: for patients with gastric cancer, this is a new promising therapeutic option; for pathologists, strengthening our role in therapy selection and emphasizing our duty of providing accurate and reproducible HER2 testing results; for all interested in understanding the biology of gastric and GEJ cancer and in discovering new possible molecular therapy targets.

This paper gives practical guidelines for diagnosis and treatment of chronic pancreatitis. Statements have been elaborated by working teams of experts, by searching for and analysing the literature, and submitted to a consensus process by using a Delphi modified procedure. The statements report recommendations on clinical and nutritional approach, assessment of pancreatic function, treatment of exocrine pancreatic failure and of secondary diabetes, treatment of pain and prevention of painful relapses. Moreover, the role of endoscopy in approaching pancreatic pain, pancreatic stones, duct narrowing and dilation, and complications was considered. Recommendations for most appropriate use of various imaging techniques and of ultrasound endoscopy are reported. Finally, a group of recommendations are addressed to the surgical treatment, with definition of right indications, timing, most appropriate procedures and techniques in different clinical conditions and targets, and clinical and functional outcomes following surgery., (Copyright © 2010 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd.. All rights reserved.)

Background: Celiac disease (CD) is a gluten-dependent enteropathy. The current standard for diagnosing CD involves obtaining 4 biopsy samples from the descending duodenum. It has been suggested that duodenal bulb biopsies may also be useful., Objective: To assess the utility of bulbar biopsies for the diagnosis of CD in pediatric patients., Design: Prospective study., Setting: Single center., Patients: Forty-seven consecutively enrolled pediatric patients with celiac serologies and a clinical suspicion of CD., Interventions: All patients underwent EGD, and 4 biopsy samples were obtained from the duodenal bulb and 4 from the descending duodenum of each child., Main Outcome Measurements: The pathologist blindly reported the Marsh histological grade for the diagnosis of CD of the bulb and descending duodenum., Results: The diagnosis of CD was histologically confirmed in 89.4% (42/47) of the cases of biopsy samples obtained from the descending duodenum and in all 47 obtained from the bulb. In 35 patients (74.5%), histology was the same in the bulb and duodenum; in 11 (23.4%) cases, the grade of atrophy was higher in the bulb than in the descending duodenum, and 5 (10.6%) had bulb histology positive for CD but negative duodenal findings. One child (2.1%) had a higher histological grade in the duodenum than in the bulb. The diagnostic gain with bulbar biopsies was 10.6%., Limitations: Small sample and absence of a comparison group (asymptomatic children with normal CD antibodies)., Conclusions: We suggest examining 4 biopsy samples from the duodenal bulb and 4 from the descending duodenum to improve diagnostic accuracy of CD., (Copyright 2010 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.)

Pancreatic endocrine tumors (PETs) may be part of hereditary multiple endocrine neoplasia type 1 (MEN1) syndrome. While MEN1 gene mutation is the only ascertained genetic anomaly described in PETs, no data exist on the cellular localization of MEN1-encoded protein, menin, in normal pancreas and PETs. A total of 169 PETs were used to assess the i) MEN1 gene mutational status in 100 clinically sporadic PETs by direct DNA sequencing, ii) immunohistochemical expression of menin in normal pancreas and 140 PETs, including 71 cases screened for gene mutations, and iii) correlation of these findings with clinical-pathological parameters. Twenty-seven PETs showed mutations that were somatic in 25 patients and revealed to be germline in 2 patients. Menin immunostaining showed strong nuclear and very faint cytoplasmic signal in normal islet cells, whereas it displayed abnormal location and expression levels in 80% of tumors. PETs harboring MEN1 truncating mutations lacked nuclear protein, and most PETs with MEN1 missense mutations showed a strong cytoplasmic positivity for menin. Menin was also misplaced in a significant number of cases lacking MEN1 mutations. In conclusion, the vast majority of PETs showed qualitative and/or quantitative alterations in menin localization. In 30% of cases, this was associated with MEN1 mutations affecting sequences involved in nuclear localization or protein-protein interaction. In cases lacking MEN1 mutations, the alteration of one of the menin interactors may have prevented its proper localization, as suggested by recent data showing that menin protein shuttles between the nucleus and cytoplasm and also affects the subcellular localization of its interactors.

Background: Ablative therapies such as radiofrequency and cryotechnology are widely used in oncological intervention but not in the pancreatic field because of their high operative risks. A new flexible bipolar ablation device (Cryotherm probe [CTP]) was developed combining radiofrequency and cryotechnology., Objective: To evaluate the efficacy of the CTP in destroying neoplastic tissue of explanted pancreatic tumors of patients with pancreatic adenocarcinoma., Design: Ex vivo clinical study., Setting: Inpatient hospital setting., Patients: This study involved 16 explanted pancreatic tumors from 16 patients., Interventions: CTP application was performed on explanted pancreatic tumors. Anatomic specimens were divided into 4 groups; each group received a predefined application time of 120 to 600 seconds., Main Outcome Measurements: The coagulation diameter (short axis) perpendicular to the device's longitudinal axis was used as the primary outcome measure., Results: All pancreatic specimens showed histological signs of coagulative necrosis. There was a positive correlation between the short axis of the obtained necrosis and duration of application (r = 0.74)., Limitations: This study was an ex vivo study with all limitations typical of this kind of study., Conclusions: The CTP is effective in destroying neoplastic pancreatic tissue, creating an ablation zone, the extent of which is related to the duration of application., (Copyright 2010 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.)

Background: Previous studies have demonstrated that the presence of serum IgA antibodies against actin filaments (AAA) in patients with celiac disease (CD) is strongly associated with mucosal damage and severe degrees of villous atrophy.The aims of the present study were (1) to verify the effectiveness of IgA-AAA in newly diagnosed CD patients in a clinical setting (2) to compare the immunofluorescence assay with ELISA assay; (3) to compare the correlation of our IgA anti-tissue transglutaminase antibodies (tTG-Ab) class with mucosal intestinal lesions., Methods: 90 patients underwent endoscopy and multiple biopsies for suspected CD on the basis of symptoms, in presence of positive tTG-Ab tests. Twenty biopsied and 25 not-biopsied subjects with negative tTG-Ab were tested as control groups. IgA-AAA assays were performed by indirect immunofluorescence using rat epithelial intestinal cells, and by ELISA with a commercial kit. tTG-Ab assay was a radio-binding assay. Intestinal specimens were collected by upper endoscopy and the histological study was done according to the Marsh's classification modified by Oberhuber (M/O). Auto-antibodies assays and histological evaluation have been performed blindly by skilled operators., Results: CD diagnosis was confirmed in 82 patients (type I M/O in 2 patients, IIIA in 18 patients, IIIB in 29 patients and IIIC in 33 patients). Two patients with type 1 lesion in presence of positive tTG-Ab and abdominal complaints, started a gluten free diet. The rate of IgA-AAA positivity (sensitivity) by IFI and ELISA in histologically proven celiac disease patients, were 5.5% and 25% patients in IIIA, 27.5% and 34.4% patients in IIIB, 78.8% and 75% in IIIC patients, respectively.Patients with normal or nearly normal mucosa, regardless of tTG-Ab status, presented negative IgA-AAA IFI assay. On the other hand, 1 patient with normal mucosa but positive tTG-Ab, also presented positive IgA-AAA ELISA. All healthy non biopsied controls had negative IgA-AAA. tTG-Ab serum concentration was significantly correlated with more severe intestinal lesion (IIIB, IIIC M/O)., Conclusions: IgA-AAA may be undetectable in presence of severe mucosal damage. Histology is still necessary to diagnose celiac disease and IgA-AAA cannot be included in usual screening tests, because it has little to offer if compared to the well-established tTG-Ab.IgA-AAA could be an adjunctive, very useful tool to support the diagnosis of CD in case of suboptimal histology, when the biopsy is to be avoided for clinical reasons, or in case of negative parents' consensus.

Currently used histopathologic criteria for the diagnosis of pancreatic endocrine tumors are still under discussion as far as to their capacity to identify prognostically different tumor subsets, which are potentially helpful for patient management. A recently developed TNM staging system and a variety of proposed histologic and clinicopathologic parameters still need to be fully validated. One hundred fifty-five pancreatic endocrine tumors encompassing all the main histologic types and stages, operated with intention to cure and then followed up for a median 126 months, were carefully investigated histologically to identify prognostically informative parameters at univariable, bivariable, and multivariable analysis. Ki67 index, mitotic rate, neuroinvasion with or without vascular, peritumoral or stromal infiltrative patterns, as well as tumor size, and association with endocrine syndromes other than insulinoma proved effective in predicting recurrence and disease-specific death among well-differentiated tumors. Poorly differentiated histologic features, more than 10 mitoses/10 high power fields, and necrosis were helpful in the identification of high-grade cancers with an invariably poor prognosis. The TNM system proved to be highly predictive of patient outcome and easy to combine with histologic and clinicopathologic parameters to classify pancreatic endocrine tumors into groups of increasing malignant potential.

Pancreatic carcinoma is a very aggressive disease with dismal prognosis. Although evidences for tumor-specific T cell immunity exist, factors related to tumor microenvironment and the presence of immunosuppressive cytokines in patients' sera have been related to its aggressive behavior. Carcinoembryonic Ag (CEA) is overexpressed in 80-90% of pancreatic carcinomas and contains epitopes recognized by CD4(+) T cells. The aim of this study was to evaluate the extent of cancer-immune surveillance and immune suppression in pancreatic carcinoma patients by comparing the anti-CEA and antiviral CD4(+) T cell immunity. CD4(+) T cells from 23 normal donors and 44 patients undergoing surgical resection were tested for recognition of peptides corresponding to CEA and viral naturally processed promiscuous epitopes by proliferation and cytokine release assays. Anti-CEA CD4(+) T cell immunity was present in a significantly higher number of normal donors than pancreatic cancer patients. Importantly, whereas CD4(+) T cells from normal donors produced mainly GM-CSF and IFN-gamma, CD4(+) T cells from the patients produced mainly IL-5, demonstrating a skew toward a Th2 type. On the contrary, the extent of antiviral CD4(+) T cell immunity was comparable between the two groups and showed a Th1 type. The immunohistochemical analysis of tumor-infiltrating lymphocytes showed a significantly higher number of GATA-3(+) compared with T-bet(+) lymphoid cells, supporting a Th2 skew also at the tumor site. Collectively, these results demonstrate that Th2-immune deviation in pancreatic cancer is not generalized but tumor related and suggests that the skew might be possibly due to factor(s) present at the tumor site.

Tumor perineural dissemination is a hallmark of human pancreatic ductal adenocarcinoma (PDAC) and represents a major source of local tumor recurrence after surgery. In this study, we provide in vitro and in vivo evidence that the chemokine receptor CX3CR1 may be involved in the neurotropism of PDAC cells to local peripheral nerves. Neoplastic cells from PDAC cell lines and surgical specimens express the chemokine receptor CX3CR1, absent in normal pancreatic ducts. Its unique ligand, the transmembrane chemokine CX3CL1, is expressed by neurons and nerve fibers. CX3CR1 + PDAC cell lines migrated in response to human recombinant CX3CL1 and specifically adhered to CX3CL1-expressing cells of neural origin via mechanisms involving activation of G proteins, beta1 integrins, and focal adhesion kinase. In vivo experiments with transplanted PDAC showed that only CX3CR1-transfected tumor cells infiltrated the local peripheral nerves. Immunohistochemistry of CX3CR1 in PDAC specimens revealed that 90% of the samples were positive with a heterogeneous pattern of expression. High receptor score was significantly associated with more prominent tumor perineural infiltration evaluated histologically (P = 0.026). Regression analyses (univariate and multivariate) showed that high CX3CR1 expression and perineural invasion were strongly associated with local and earlier tumor recurrence (P = 0.007). Collectively, this study shows that the CX3CR1 receptor may be involved in PDAC tumor neurotropism and is a relevant and independent risk factor to predict an early local tumor relapse in resected patients. Thus, the CX3CR1-CX3CL1 axis could represent a valuable therapeutic target to prevent tumor perineural dissemination in pancreatic cancer.

The cytological Ki-67 expression measured on cytological samples collected by endoscopic ultrasonography-guided fine needle aspiration cytology (EUS-FNAC) may provide pre-operative indications for pancreatic endocrine tumours (PETs) management. The aim of our study was to assess reliability of Ki-67 expression measured on cytological samples obtained by EUS-FNAC in patients with PETs. Eighteen patients with PETs underwent EUS-FNAC before surgery. Ki-67 expression was measured on FNACs and on histological sections. Using a cut-off of 2%, percent agreement of Ki-67 expression on cytological and histological samples was 89% (k-statistic: 0.78, 95% confidence intervals (95% CI): 0.5, 1.0). Using cut-off values of 2 and 10%, percent agreement was 78% (k-statistic: 0.65, 95% CI: 0.3, 0.9). Ki-67 expression measured on cytological samples obtained by EUS-FNAC before surgery showed good agreement with that measured on histological samples.

Background and Aim: Celiac disease (CD) is a common condition but often it goes unrecognized because characteristic histopathological abnormalities must be found to confirm the diagnosis. A way is needed to select patients who need biopsy of the duodenal mucosa to detect CD. No data are currently available on the use of in vivo optical coherence tomography (OCT), during real-time endoscopic imaging, in the small intestine and, particularly, in the diagnosis of CD. The aim of the present study was to test the utility of OCT in patients undergoing esophagogastroduodenoscopy (EGD) for histological diagnosis., Methods: Eighteen patients with suspected CD (positive for antigliadin, antiendomysial and antitransglutaminase antibodies) and 22 dyspeptic subjects (negative for these antibodies) who were also examined by EGD, were prospectively enrolled. OCT scans of descending duodenum were taken during diagnostic EGD, with biopsies of the same duodenal area. OCT images and histological specimens were evaluated blindly, analysis being done independently by a gastroenterologist and a pathologist. Three patterns of intestinal villous morphology were considered (1, no atrophy; 2, mild atrophy; 3, marked atrophy)., Results: Concordance was total between OCT and histology for villi morphology in both patients and normal subjects., Conclusions: OCT appears to be a promising method for correctly identifying villous atrophy; it may help in selecting patients for intestinal biopsies, considering the limited usefulness of endoscopic criteria, and may also help the endoscopist to perform target biopsies in mucosal areas where the villi are damaged or absent, considering that CD often causes patchy mucosal lesions.

Congenital Hyperinsulinism of Infancy (CHI) is a genetically heterogeneous disorder characterized by profound hypoglycemia related to inappropriate insulin secretion. Two histopathologically and genetically distinct groups are recognized among patients with CHI due to ATP-sensitive potassium channel (KATP) defects: a diffuse type (Di-CHI), which involves the whole pancreas, and a focal form (Fo-CHI), which shows adenomatous islet-cell hyperplasia of a particular area within the normal pancreas. The beta-cell KATP channel consists of two essential subunits: Kir6.2 encoded by the KCNJ11 gene which is the pore-forming unit and belongs to the inwardly rectifying potassium channel family, and SUR1 (sulfonylurea receptor 1) encoded by the ABCC8 gene, which belongs to the ATP-binding cassette (ABC) transporter family. The KATP channel is an octameric complex of four Kir6.2 and four SUR1 subunits. More than one hundred mutations have been found in KATP channel genes ABCC8 and KCNJ11, but to date only twenty mutations have been identified in KCNJ11, most of them are missense mutations and only one is a single base deletion. The Fo-CHI has been demonstrated to arise in individuals who have a germline mutation in the paternal allele of ABCC8 or KCNJ11 in addition to a somatic loss of the maternally derived chromosome region 11p15 in adenomatous pancreatic beta-cells, while Di-CHI predominantly arises from the autosomal recessive inheritance of KATP channel gene mutations. Here we describe the molecular findings in nine children who presented, in the neonatal period, with signs and symptoms of hypoglycemia and diagnosed affected by CHI according to international diagnostic criteria. Direct sequencing of the complete coding exon and promoter region of KCNJ11 gene showed, in two Italian patients, two new heterozygous mutations which result in the appearance of premature translation termination codons resulting in the premature end of Kir6.2. Interestingly most of the CHI mutations detected in other population studies are situated in the ABCC8 gene.

Background & Aims: The Marsh-Oberhuber classification of duodenojejunal mucosal lesions is currently used for celiac disease. A more simplified classification, which is based on 3 villous morphologies (A, non-atrophic; B1, atrophic, villous-crypt ratio <3:1; B2, atrophic, villi no longer detectable) and an intraepithelial lymphocyte count of >25/100 enterocytes, has recently been proposed. The aim of the study was to asses the interobserver agreement between different pathologists in classifying celiac disease lesions according to both Marsh-Oberhuber and the new classification system., Methods: Sixty patients were selected for the study: 10 subjects without celiac disease, 13 celiac patients with normal villi but a pathologic increase in intraepithelial lymphocytes >25/100 and hyperplastic crypts, and 37 patients with celiac disease with villous atrophy. Sixty slides were sent to 6 pathologists, who were blinded to each other and were not given any clinical information. Each pathologist received the set of biopsy specimens on 2 separate occasions and had to evaluate them according to both grading systems in a random order. The kappa statistic was used to assess agreement between each pair of pathologists., Results: Overall, mean kappa values were 0.35 (fair) for the Marsh-Oberhuber classification versus 0.55 (moderate) for the new classification system., Conclusions: The new classification for duodenal pathology in celiac disease gives better interobserver agreement compared with the more cumbersome Marsh-Oberhuber classification and contributes to the validity of diagnosis in celiac disease.

Background: Optical coherence tomography (OCT) permits high-resolution, real-time, infrared-generated imaging of tissue microstructures by a probe inserted through the endoscope operative channel. Resolution is approximately 10 microm and the penetration depth of the near-focus probe is about 1 mm. The probe can be inserted into the main pancreatic duct (MPD) through a standard endoscopic retrograde cholangiopancreatography catheter., Aims and Methods: To assess the ability of OCT to identify the structure of the MPD, to distinguish normal and malignant MPD epithelium, and to assess intra- and interobserver reproducibility of OCT images. Multiple sections of neoplastic and non-neoplastic segments of 10 consecutive surgical pancreatic specimens were obtained from patients with pancreatic head adenocarcinoma who had undergone Whipple resection, and repeated OCT radial and longitudinal scanning was done within 1 h of resection and before pathological examination. We compared 249 good-quality images with 100 histopathological sections., Results: OCT recognized a definite, different pattern in 82.9% of tumor-free and in 97.6% of tumor-involved specimens; sensitivity and specificity for discrimination between adenocarcinoma and normal tissue were 78.6% and 88.9%, respectively. Inflammatory and dysplastic changes of the MPD showed an OCT pattern similar to that of the normal tissue in 53.3% of images. Overall, intraobserver reproducibility ranged from 85.1% to 100% and interobserver reproducibility ranged from 69.9% to 100% and from 89.7% to 100% for tumor-free and tumor-involved segments, respectively., Conclusions: OCT identified the neoplastic and non-neoplastic MPD layer structure and appeared to be a reproducible technique. In non-neoplastic conditions, OCT appeared unable to differentiate between normal and abnormal tissues in about half of the cases.

Several reports suggest that enteric cholinergic neurons are subject to a tonic inhibitory modulation, whereas few studies are available concerning the role of facilitatory pathways. Glutamate, the main excitatory neurotransmitter in the central nervous system (CNS), has recently been described as an excitatory neurotransmitter also in the guinea-pig enteric nervous system (ENS). The present study aimed at investigating the presence of glutamatergic neurons in the ENS of the human colon. At this level, the presence of ionotropic glutamate receptors of the NMDA type, and their possible interaction with the enteric cholinergic function was also studied. In the human colon, L-glutamate and NMDA concentration dependently enhance spontaneous endogenous acetylcholine overflow in Mg2+-free buffer, both effects being significantly reduced by the antagonists, (+/-)-2-amino-5-phosphonopentanoic acid (+/- AP5) and 5,7-diCl-kynurenic acid. In the presence of Mg2+, the facilitatory effect of L-glutamate changes to inhibition, while the effect of NMDA is significantly reduced. In addition, morphological investigations reveal that glutamate- and NR1-immunoreactivities are present in enteric cholinergic neurons and glial cells in both myenteric and submucosal plexus. These findings suggest that, as described for the guinea-pig ileum, glutamatergic neurons are present in enteric plexuses of the human colon. Modulation of the cholinergic function can be accomplished through NMDA receptors.

Angiogenesis, a process related to tumor growth and malignancy, is stimulated by several growth factors. Among these is vascular endothelial growth factor (VEGF), which acts on endothelial cells by binding with 2 specific receptors, VEGFR1 and VEGFR2. Recent studies have demonstrated that VEGF expression is correlated with microvessel density (MVD) and tumor progression. Digestive endocrine tumors are heterogeneous neoplasms exhibiting variable biological aggressiveness and behavior that often are not predictable on morphologic grounds alone. The aims of this study were to evaluate the expression of VEGF, VEGFR1, and VEGFR2 in digestive endocrine tumors and to examine its correlation with MVD and malignancy. A total of 84 specimens from endocrine neoplasms and normal gut and pancreatic tissue were immunohistochemically studied using specific antibodies directed against VEGF, VEGFR1, VEGFR2, endothelial antigens, and gastroenteropancreatic hormones. Ultrastructural immunocytochemistry was performed to identify the cellular localization of VEGF and the VEGFRs. In normal tissues, VEGF immunoreactivity was detected in G cells and PP cells. Ultrastructurally, VEGF was localized within secretory granules. The VEGFRs were not significantly expressed by normal endocrine cells. VEGF-immunoreactive (IR) cells were detected in 40 of 83 tumors, mainly G cell and enterochromaffin cell neoplasms. VEGFR1-IR cells were found in 44 of 82 tumors, and VEGFR2-IR cells were found in 55 of 82 tumors, with no predilection for any specific tumor type. The expression of VEGF and its receptors did not correlate with MVD or malignancy. These results suggest that in normal tissues, endothelial functions may be regulated by VEGF produced by some endocrine cells and that a VEGF/VEGFR binding mechanism may be involved in tumorigenesis, but not in tumor progression and aggressiveness., (Copyright 2003, Elsevier Science (USA). All rights reserved.)

In this presentation the gastrointestinal pancreatic endocrine tumors (ETs) are subdivided into well differentiated ETs and poorly differentiated ETs. Well differentiated ETs are subclassified into ETs with benign behavior, ETs with uncertain behavior and well differentiated endocrine carcinomas. The criteria allowing a distinction among these main types of neoplasms are listed according to the site of origin of the ETs. In addition, the main functional types of ETs of the pancreas, stomach, duodenum, jejunum, ileum, appendix and large bowel are briefly described.

Alterations of DNA mismatch repair (MMR) genes are involved in carcinogenesis of sporadic and inherited human cancers characterised by instability of DNA microsatellite sequences (MSI). MSI tumours are usually identified using molecular analysis. In the present investigation, hMLH1 and hMSH2 immunohistochemistry was tested in order to evaluate the utility of this method in predicting MMR deficiency. Colorectal (72), gastric (68), endometrial (44) and ovarian (17) carcinomas were independently evaluated for familial history, histological type of tumour, MSI status and immunohistochemical results. Loss of expression of either hMLH1 or hMSH2 was observed in 51 of 55 (92.8%) MSI tumours, while 145 of 146 microsatellite stable (MSS) tumours expressed both the hMLH1 and hMSH2 gene products. Independently of tumour site, an overall agreement between immunohistochemical and molecular results was observed in 15 hereditary non-polyposis colorectal cancer-related tumours. Among sporadic tumours, only 2 of 60 colorectal and 2 of 66 gastric carcinomas, displaying MSI, expressed both hMLH1 and hMSH2 gene products. All 39 endometrial and 16 ovarian tumours presented a concordant molecular and immunohistochemical profile. These data show that immunohistochemistry is an accurate and rapid method to predict the presence of defective DNA MMR genes and to identify both sporadic and familial MSI tumours.

Aims and Background: Epidemiological investigations on the frequency of hereditary nonpolyposis colorectal cancer (HNPCC) syndrome are few and have shown a variable worldwide incidence ranging from 1% to 7% of all colorectal cancers (CRCs). In Italy, relevant differences have been observed: 2.8-3% of all CRCs in northern regions and less than 1% in southern regions. The aim of the present study was to investigate the HNPCC incidence in a selected area of northern Italy belonging to the Lombardy Cancer Registry., Methods and Study Design: We analyzed 197 consecutive patients with newly diagnosed CRCs, histologically verified, and resident in two areas of the Lombardy Cancer Registry. For each case, genetic counseling with at least three generations pedigree reconstruction, HNPCC classification according to Amsterdam criteria, molecular analysis for microsatellite instability and immunohistochemistry for hMLH1 and hMSH2 were performed., Results: A very low frequency (0.5%) of HNPCC fulfilling the Amsterdam criteria was found in comparison to the other Italian areas. Such an incidence seems to be due to actual population differences and reflects a genetic heterogeneity., Conclusions: The data underline the importance of a precise knowledge of actual HNPCC incidence in different populations in order to optimize effectiveness and efficiency of screening programs for the disease.

Background: Microsatellite instability (MI) is a biological characteristic of most tumors involved in hereditary non-polyposis colorectal cancer (HNPCC). This disease appears to be caused by germline mutations in mismatch repair (MMR) genes, which are responsible for repairing single base-pair mismatches. At least five human genes participate in MMR. MI also occurs in 10%-15% of sporadic colorectal cancers. Because MI detection has been suggested as an alternative diagnostic tool for identification of HNPCC families, in this study we analyzed the MI pattern in 100 consecutive colorectal carcinomas in order to correlate them with the clinicopathologic features and family histories of the patients., Patients and Methods: A series of 100 colorectal cancers was evaluated for MI with 10 polymerase chain reaction primer sets. Instability results were compared with family history and other clinical and biological characteristics., Results: MI was detected in 36 of 100 cancers, 27 of which showed low instability and nine a high instability. The low- and high-instability cases showed similar clinicopathological characteristics, and significantly positive associations were observed between MI and mucinous histological type (P = 0.0001) and MI and peritumoral lymphocytic infiltration (P = 0.01). A single HNPCC family was identified in the high-grade MI group, while two families belonged to the MI-negative group., Conclusions: Our data suggest that MI screening is probably not an efficient strategy for identifying HNPCC cases. MI does, however, appear capable of defining a category of colorectal cancers with favourable prognostic features and should be investigated at least in all cases of mucinous adenocarcinomas.