Hippocampal Microglia Activation Induced by Acute Pancreatic Injury in Rats.

BACKGROUND: Acute pancreatitis is an inflammation of the pancreatic glandular parenchyma that causes injury with or without the destruction of pancreatic acini. Clinical and experimental evidence suggest that certain systemic proinflammatory mediators may be responsible for initiating the fundamental mechanisms involved in microglial reactivity. Here, we investigated the possible repercussions of acute pancreatitis (AP) on the production of inflammatory mediators in the brain parenchyma focusing on microglial activation in the hippocampus. METHODS: The acute pancreatic injury in rats was induced by a pancreas ligation surgical procedure (PLSP) on the splenic lobe, which corresponds to approximately 10% of total mass of the pancreas. Blood samples were collected via intracardiac puncture for the measurement of serum amylase. After euthanasia, frozen or paraffin-embedded brains and pancreas were analyzed using qRT-PCR or immunohistochemistry, respectively. RESULTS: Immunohistochemistry assays showed a large number of Iba1 and PU.1-positive cells in the CA1, CA3, and dentate gyrus (DG) regions of the hippocampus of the PLSP group. TNF-α mRNA expression was significantly higher in the brain from PLSP group. NLRP3 inflammasome expression was found to be significantly increased in the pancreas and brain of rats of the PLSP group. High levels of BNDF mRNA were found in the rat brain of PLSP group. In contrast, NGF mRNA levels were significantly higher in the control group versus PLSP group. CONCLUSION: Our findings suggest that AP has the potential to induce morphological changes in microglia consistent with an activated phenotype.

Morphological characteristics, classifications and difficulties in the use of diagnostic criteria for serrated lesions of the large intestine

Abstract: Introduction Colorectal carcinoma (CRC) is the most common gastrointestinal neoplasm in the world, accounting for 15% of cancer-related deaths. This condition is related to different molecular pathways, among them the recently described serrated pathway, whose characteristic entities, serrated lesions, have undergone important changes in their names and diagnostic criteria in the past thirty years. The multiplicity of denominations and criteria over the last years may be responsible for the low interobserver concordance (IOC) described in the literature. Objectives: The present study aims to describe the evolution in classification of serrated lesions, based on the last three publications of theWorld Health Organization (WHO) and the reproducibility of these criteria by pathologists, based on the evaluation of the IOC. Methods: A search was conducted in the PubMed, ResearchGate and Portal Capes databases, with the following terms: sessile serrated lesion; serrated lesions; serrated adenoma; interobserver concordance; andreproducibility.Articlespublished since 1990were researched. Results and Discussion: The classification of serrated lesions in the past thirty years showed different denominations and diagnostic criteria. The reproducibility and IOC of these criteria in the literature, based on the kappa coefficient, varied in most studies, from very poor to moderate. Conclusions: Interobserver concordance and the reproducibility of microscopic criteria may represent a limitation for the diagnosis andappropriatemanagementof these lesions. It is necessary to investigate diagnostic tools to improve the performance of the pathologist's evaluation, for better concordance, and, consequently, adequate diagnosis and treatment. (AU)

Colonic tuberculosis presenting as intestinal subocclusion in a patient with neuroendocrine tumor: a case report.

Extra-pulmonary tuberculosis (EPT) is responsible for approximately 14% of all tuberculosis cases in Brazil. The incidence of EPT is increasing slightly and is often associated with human immunodeficiency virus infection and other causes of immunosuppression. The association of EPT and cancer is poorly documented. Here we present a rare case of intestinal subocclusion that was supposed to be caused by cancer and was caused by colonic tuberculosis (CT) in a patient with metastatic neuroendocrine tumor (NET). A 61-year-old woman presented with one-year history of abdominal pain, diarrhea and weight loss. An abdominal CT scan (ACTS) showed liver, peritoneal and lymph nodes metastasis. Colonoscopy revealed a subocclusive lesion in the descendent colon. She underwent an urgent laparoscopy and transverse colostomy. The liver biopsy revealed a well differentiated grade 2 NET and the mycobacterial culture confirmed tuberculosis in the colonic lesion. Anti-tuberculosis was prescribed, and somatostatin analogue therapy was introduced one month later. The tuberculosis treatment was finished, and the patient remained on somatostatin analogue for 21 months. During this time the symptoms of abdominal pain and diarrhea disappeared and her body weight increased 35% over her baseline weight. Then, diarrhea, flushing and abdominal pain returned, and a new ACTS confirmed progressive disease. Interferon was added to her treatment with satisfactory control of symptoms. She was forwarded to another hospital to be treated with 177Lu-DOTATOC. The symptoms improved and the patient remained symptom free for more than a year, and now she has a new disease progression. The patient will be evaluated for retreatment with 177Lu-DOTATOC. Advanced NET may be a devastating disease enough to predispose the patient to EPT. We must keep this hypothesis in the differential diagnosis of our patients since symptoms of CT are usually nonspecific. At colonoscopy, radiological features are strictures, colitis and polypoidal lesions and complications such as bowel perforation or fistula must be in mind. It is particularly important those with advanced disease in endemic areas of tuberculosis.

CD57 as a routine neuroendocrine marker for liver metastasis.

BACKGROUND: The characterization of hepatic metastases as having neuroendocrine origins is essential and the main markers currently used are chromogranin A (CgA) and synaptophysin (Syn). However, these markers may exhibit certain limitations, and the use of CD56 and CD57 can also be considered, although, due to low specificity, their use is discouraged. AIM: This study sought to compare the immunohistochemical expression of these markers in hepatic metastases of neuroendocrine neoplasms (NEN). MATERIALS AND METHODS: Eighteen samples, were used for immunohistochemical staining with CgA, Syn, CD56, and CD57 antibodies. The immunostaining reactions were compared according to its intensity (I), the percentage of labeled cells (P), and a final score (I × P). Statistical agreement between the markers was also evaluated. RESULTS: CD57 was expressed in the highest number of cases and also showed the most intense expression. CgA showed the highest number of cases with more than 80% positively stained area (72.2%), followed by CD57 (61.1%). The highest average score (I × P) was obtained for CD57 (9.1 ± 4.1). The best indices of agreement were between CgA and CD57 with respect to positivity (P = 0.021) and score (P = 0.014). According to the primary site, stomach/duodenum, lungs, and undetermined subgroups showed the highest average scores for CD57, followed by CgA. For the small bowel subgroup, the highest average score was obtained for CgA, followed by CD57. CONCLUSION: Our results highlight the importance of CD57 in the evaluation of hepatic metastases of NEN and indicate that this marker should be included with CgA and Syn in routine diagnostic panels.

Fibrosis assessment using FibroMeter combined to first generation tests in hepatitis C.

AIM: To evaluate the performance of FibroMeterVirus3G combined to the first generation tests aspartate aminotransferase-to-platelet ratio index (APRI) or Forns index to assess significant fibrosis in chronic hepatitis C (CHC). METHODS: First generation tests APRI or Forns were initially applied in a derivation population from Rio de Janeiro in Brazil considering cut-offs previously reported in the literature to evaluate significant fibrosis. FibroMeterVirus3G was sequentially applied to unclassified cases from APRI or Forns. Accuracy of non-invasive combination of tests, APRI plus FibroMeterVirus3G and Forns plus FibroMeterVirus3G was evaluated in the Brazilian derivation population. APRI plus FibroMeterVirus3G combination was validated in a population of CHC patients from Angers in France. All patients were submitted to liver biopsy staged according to METAVIR score by experienced hepatopathologists. Significant fibrosis was considered as METAVIR F ≥ 2. The fibrosis stage classification was used as the reference for accuracy evaluation of non-invasive combination of tests. Blood samples for the calculation of serum tests were collected on the same day of biopsy procedure or within a maximum 3 mo interval and stored at -70 °C. RESULTS: Seven hundred and sixty CHC patients were included (222 in the derivation population and 538 in the validation group). In the derivation population, the FibroMeterVirus3G AUROC was similar to APRI AUROC (0.855 vs 0.815, P = 0.06) but higher than Forns AUROC (0.769, P < 0.001). The best FibroMeterVirus3G cut-off to discriminate significant fibrosis was 0.61 (80% diagnostic accuracy; 75% in the validation population, P = 0.134). The sequential combination of APRI or Forns with FibroMeterVirus3G in derivation population presented similar performance compared to FibroMeterVirus3G used alone (79% vs 78% vs 80%, respectively, P = 0.791). Unclassified cases of significant fibrosis after applying APRI and Forns corresponded to 49% and 54%, respectively, of the total sample. However, the combination of APRI or Forns with FibroMeterVirus3G allowed 73% and 77%, respectively, of these unclassified cases to be correctly evaluated. Moreover, this combination resulted in a reduction of FibroMeterVirus3G requirement in approximately 50% of the entire sample. The stepwise combination of APRI and FibroMeterVirus3G applied to the validation population correctly identified 74% of patients with severe fibrosis (F ≥ 3). CONCLUSION: The stepwise combination of APRI or Forns with FibroMeterVirus3G may represent an accurate lower cost alternative when evaluating significant fibrosis, with no need for liver biopsy.

Immunohistochemical angiogenic biomarkers in hepatocellular carcinoma and cirrhosis: correlation with pathological features.

OBJECTIVE: To investigate immunohistochemical markers of angiogenesis and their association with pathological prognostic features in hepatocellular carcinoma and cirrhotic liver. METHODS: Vascular endothelial growth factor, CD105, and cyclooxygenase-2 were immunohistochemically detected in 52 hepatocellular carcinoma tissue samples and 48 cirrhotic liver tissue samples. Semiquantitative measurements of vascular endothelial growth factor and cyclooxygenase-2 were evaluated considering the degree and intensity of immunostaining based on a 7-point final scoring scale. CD105 microvascular density (MVD-CD105) was measured using automated analysis. Morphological aspects evaluated in the hepatocellular carcinoma samples included size (≤2 and >2 cm), differentiation grade, and microvascular invasion. RESULTS: The mean vascular endothelial growth factor immunoreactivity score was slightly higher in the hepatocellular carcinoma samples (4.83±1.35) than the cirrhotic liver (4.38±1.28) samples. There was a significant and direct correlation between these mean scores (rs=0.645, p=0.0001). Cyclooxygenase-2 was expressed in all the cirrhotic liver samples but was only found in 78% of the hepatocellular carcinoma samples. The mean cyclooxygenase-2 score was higher in the cirrhotic liver samples (4.85±1.38) than the hepatocellular carcinoma samples (2.58±1.68), but there was no correlation between the scores (rs=0.177, p=0.23). The mean CD105 percentage in the hepatocellular carcinoma samples (11.2%) was lower than that in the cirrhotic samples (16.9%). There was an inverse relationship in MVD-CD105 expression between the hepatocellular carcinoma and cirrhotic samples (rs=-0.78, p=0.67). There were no significant associations between vascular endothelial growth factor expression and morphological characteristics. Cyclooxygenase-2 and CD105 were associated with hepatocellular carcinoma differentiation grade (p=0.003 and p=0.05, respectively). CONCLUSION: Vascular endothelial growth factor, cyclooxygenase-2, and MVD-CD105 were highly expressed in cirrhotic liver compared to hepatocellular carcinoma and might be involved in liver carcinogenesis. Additionally, cyclooxygenase-2 and CD105 might be involved in hepatocellular carcinoma differentiation grade.

Immunohistochemical angiogenic biomarkers in hepatocellular carcinoma and cirrhosis: correlation with pathological features

OBJECTIVE To investigate immunohistochemical markers of angiogenesis and their association with pathological prognostic features in hepatocellular carcinoma and cirrhotic liver. METHODS Vascular endothelial growth factor, CD105, and cyclooxygenase-2 were immunohistochemically detected in 52 hepatocellular carcinoma tissue samples and 48 cirrhotic liver tissue samples. Semiquantitative measurements of vascular endothelial growth factor and cyclooxygenase-2 were evaluated considering the degree and intensity of immunostaining based on a 7-point final scoring scale. CD105 microvascular density (MVD-CD105) was measured using automated analysis. Morphological aspects evaluated in the hepatocellular carcinoma samples included size (≤2 and >2 cm), differentiation grade, and microvascular invasion. RESULTS The mean vascular endothelial growth factor immunoreactivity score was slightly higher in the hepatocellular carcinoma samples (4.83±1.35) than the cirrhotic liver (4.38±1.28) samples. There was a significant and direct correlation between these mean scores (rs=0.645, p=0.0001). Cyclooxygenase-2 was expressed in all the cirrhotic liver samples but was only found in 78% of the hepatocellular carcinoma samples. The mean cyclooxygenase-2 score was higher in the cirrhotic liver samples (4.85±1.38) than the hepatocellular carcinoma samples (2.58±1.68), but there was no correlation between the scores (rs=0.177, p=0.23). The mean CD105 percentage in the hepatocellular carcinoma samples (11.2%) was lower than that in the cirrhotic samples (16.9%). There was an inverse relationship in MVD-CD105 expression between the hepatocellular carcinoma and cirrhotic samples (rs=-0.78, p=0.67). There were no significant associations between vascular endothelial growth factor expression and morphological characteristics. Cyclooxygenase-2 and CD105 were associated with hepatocellular carcinoma differentiation grade (p=0.003 and p=0.05, respectively). CONCLUSION Vascular endothelial growth factor, cyclooxygenase-2, and MVD-CD105 were highly expressed in cirrhotic liver compared to hepatocellular carcinoma and might be involved in liver carcinogenesis. Additionally, cyclooxygenase-2 and CD105 might be involved in hepatocellular carcinoma differentiation grade.

Histopathological study comparing native and post-transplant recurrent chronic hepatitis C with emphasis on confounders with acute cellular rejection / Estudo histopatológico comparativo da hepatite crônica C nativa e recorrente pós-transplante com ênfase em achados semelhantes à rejeição celular aguda

ABSTRACT Introduction: Histological analyses of post-transplant liver biopsies may be difficult in distinguishing recurrent chronic hepatitis C (CHC) from other causes of graft dysfunction, especially acute cellular rejection (ACR). Objective: The aim of this study was to compare the histological characteristics of liver biopsies with CHC in transplant and non-transplant patients with hepatitis C virus (HCV) infection and assess the occurrence of findings common to ACR. Methods: We studied 40 biopsies from non-transplant and 30 biopsies from post-transplant patients, according to the Ishak score for necroinflammatory activity grade and stage of fibrosis. We also assessed the inflammatory infiltrate, steatosis, ductal changes, portal endotheliitis and central perivenulitis. Results: We found predominance of mild grade and stage in both groups. The portal inflammatory infiltrate was also mild and mainly lymphocytic in the two groups. Ductal changes were more frequent in the non-transplant patients. Steatosis was also mild in both groups, but predominated in non-transplant CHC patients. Portal endotheliitis occurred in 42.5% and 40% in non-transplant and post-transplant CHC, respectively. The frequency of centrilobular endotheliitis was similar in both groups. Conclusion: Histological findings in chronic hepatitis C are similar in non-transplant and post-transplant patients. In addition, morphological features characteristic of ACR are also observed in HCV infection of native livers as well as in the graft of patients with recurrent infection after transplantation.

RESUMO Introdução: A análise histológica de biópsias hepáticas pós-transplante pode trazer dificuldades na distinção entre hepatite crônica C (HCC) recorrente e outras causas de disfunção do enxerto, sobretudo rejeição celular aguda (RCA). Objetivo: Comparar as características histológicas de biópsias hepáticas de pacientes transplantados e não transplantados portadores de HCC, além de avaliar a presença de achados comuns à RCA. Métodos: Foram estudadas 40 biópsias de pacientes não transplantados e 30 de transplantados, de acordo com o escore de Ishak para grau de atividade necroinflamatória e estágio de fibrose. Foram ainda avaliadas as características do infiltrado inflamatório, da esteatose, das alterações ductais e da endotelite portal e da perivenulite central. Resultados: Em ambos os grupos, houve predomínio de leve grau de atividade necroinflamatória e leve fibrose. O infiltrado inflamatório portal também foi leve e predominantemente linfocítico em ambos os grupos. Alterações ductais foram mais frequentes em pacientes não transplantados. Esteatose também foi leve em ambos os grupos, mas predominou nos pacientes não transplantados. Endotelite portal ocorreu em 42,5% e 40% em HCC não transplantada e HCC pós-transplante, respectivamente. A frequência de endotelite centrolobular foi semelhante nos dois grupos. Conclusão: Os achados histológicos na HCC são semelhantes em pacientes transplantados e não transplantados. Além disso, características morfológicas da RCA estão presentes na HCC, tanto em fígados nativos como em enxertos de pacientes com infecção recorrente após transplante.

RASSF1A and DOK1 Promoter Methylation Levels in Hepatocellular Carcinoma, Cirrhotic and Non-Cirrhotic Liver, and Correlation with Liver Cancer in Brazilian Patients.

Hepatocellular carcinoma (HCC) is the second most common cause of cancer mortality worldwide. Most cases of HCC are associated with cirrhosis related to chronic hepatitis B virus or hepatitis C virus infections. Hypermethylation of promoter regions is the main epigenetic mechanism of gene silencing and has been involved in HCC development. The aim of this study was to determine whether aberrant methylation of RASSF1A and DOK1 gene promoters is associated with the progression of liver disease in Brazilian patients. Methylation levels were measured by pyrosequencing in 41 (20 HCC, 9 cirrhotic, and 12 non-cirrhotic) liver tissue samples. Mean rates of methylation in RASSF1A and DOK1 were 16.2% and 12.0% in non-cirrhotic, 26.1% and 19.6% in cirrhotic, and 59.1% and 56.0% in HCC tissues, respectively, showing a gradual increase according to the progression of the disease, with significantly higher levels in tumor tissues. In addition, hypermethylation of RASSF1A and DOK1 was found in the vast majority (88%) of the HCC cases. Interestingly, DOK1 methylation levels in HCC samples were significantly higher in the group of younger (<40 years) patients, and higher in moderately differentiated than in poorly differentiated tumors (p < 0.05). Our results reinforce the hypothesis that hypermethylation of RASSF1A and DOK1 contributes to hepatocarcinogenesis and is associated to clinicopathological characteristics. RASSF1A and DOK1 promoter hypermethylation may be a valuable biomarker for early diagnosis of HCC and a potential molecular target for epigenetic-based therapy.

Exogenous pulmonary surfactant prevents the development of intra-abdominal adhesions in rats.

Intra-abdominal adhesions are major post-operative complications for which no effective means of prevention is available. We aimed to evaluate the efficacy of exogenous pulmonary surfactant administration in the prevention of post-operative abdominal adhesions. Rats were randomly assigned to undergo laparotomy (L) or gastroenterostomy (GE) and then treated with surfactant (groups L-S and GE-S, respectively). Intra-abdominal adhesions, collagen fibre content, metalloproteinase (MMP)-9, expression of growth factors (TGF-ß, KGF and VEGF), type III procollagen (PCIII) and pro-caspase 3, as well as isolectin B4 and ED1-positive cells expressing MMP-9, were evaluated. Groups treated with surfactant (GE-S and L-S) exhibited fewer adhesions. A significant reduction in collagen fibre content was observed in GE-S compared to GE animals (P < 0.001). In situ and gelatin zymography analysis showed higher MMP-9 expression and activity in the GE-S group compared to the GE group (P < 0.05). ED1-positive cell counts were significantly higher in the GE-S group (P < 0.001) than in the GE group. Virtually all cells positive for ED1 were MMP-9+. Double-labelling of MMP-9 with IB4 showed no significant differences between GE-S and GE groups. TGF-ß, KGF, PCIII and pro-caspase-3 mRNA expression decreased significantly in GE-S compared to GE animals (P < 0.05). Surfactant administration also reduced apoptosis in the GE-S group. These findings suggest that surfactant reduces the intra-abdominal adhesions triggered by laparotomy and gastrointestinal anastomosis, thus preventing fibrosis formation at the peritoneal surfaces. This preclinical study suggests an innovative treatment strategy for intra-abdominal adhesions with surfactant and to endorse its putative mechanism of action.

Intermediate fibrosis staging in hepatitis C: a problem not overcome by optimal samples or pathologists' expertise.

BACKGROUND AND AIMS: The prediction of intermediate stage of fibrosis in chronic hepatitis C represents a prognostic factor for disease progression. Studies evaluating biopsy performance in intermediate stage considering current patterns of liver samples and pathologists' variability are scarce. We aimed to evaluate the effect of optimal liver specimens (≥ 20 mm and/or ≥ 11 portal tracts) and pathologists' expertise on agreement for intermediate stage of fibrosis in chronic hepatitis C. MATERIAL AND METHODS: Guided biopsies with large TruCut needle were initially scored by four pathologists with different expertise in liver disease and posteriorly reviewed by a reference hepatopathologist to evaluate fibrosis agreement. RESULTS: Of the 255 biopsies initially selected, 240 met the criteria of an optimal fragment (mean length 24 ± 5 mm; 16 ± 6 portal tracts) and were considered for analysis. The overall agreement among all fibrosis stages was 77% (κ = 0.66); intraobserver and interobserver agreement was, respectively, 97% (k = 0.96) and 73% (κ = 0.60). Excluded samples (< 20 mm and < 11 portal tracts) presented a lower agreement (40%; κ = 0.24). Stratifying fibrosis stages, an interobserver agreement of 42% was found in intermediate stage (F2), ranging from 0 to 56% according to pathologists' expertise, compared to 97% in mild (F0-F1) and 72% in advanced fibrosis (≥ F3) (p < 0.001). Of the 23% misclassified cases, fibrosis understaging occurred in 82% of specimens, predominantly in F2, even when evaluated by a hepatopathologist. CONCLUSIONS: Liver biopsy presents intrinsic limitations to assess intermediate stage of fibrosis not overcome by optimal samples and experienced pathologists' analysis, and should not be considered the gold standard method to evaluate intermediate fibrosis in chronic hepatitis C.

Prognostic angiogenic markers (endoglin, VEGF, CD31) and tumor cell proliferation (Ki67) for gastrointestinal stromal tumors.

AIM: To evaluate the correlation between the immunoexpression of angiogenic markers [CD31, CD105 and vascular endothelial growth factor (VEGF)], proliferative index (Ki67), and prognosis of patients with gastrointestinal stromal tumors (GIST). METHODS: This is a retrospective study of 54 GIST cases. Medical records were searched to obtain the GIST patients' demographic and clinical data, and paraffin-embedded blocks of tumor samples were retrieved from the hospital archives to conduct a new immunohistochemical evaluation. The tumor samples of GIST patients were subject to immunohistochemical evaluation for endoglin (CD105), CD31, VEGF, and Ki67 expression. The CD105 and CD31 intratumoral microvascular density (IMVD) was measured using automated analysis. We determined the correlation between the immunoexpression of CD105, CD31, VEGF, Ki67 and prognosis. In addition, we conducted a cutoff analysis using the receiver-operating characteristic curve. VEGF positivity was classified as either null/weak or strong. Ki67 was evaluated using a cutoff of 5% positive cells. The prognosis was classified as good (patient alive without recurrence) or poor (patient with recurrence/death). RESULTS: The distribution of tumor sites among the 54 analyzed samples was as follows: 27 (50%) in the stomach, 20 (37.1%) in the small intestine, 6 (11.1%) in the colon, and 1 (1.8%) in the esophagus. The size of the tumors ranged from 2 to 33 cm (median: 8 cm); in 12 cases (22.2%), the tumor was below 5 cm at the largest diameter, but in 42 cases (77.7%), the tumor was larger than 5 cm. The means of CD105 and CD31 were significantly higher in the group with poor prognosis (P < 0.001). The cut-off values of CD105 (> 1.2%) and CD31 (> 2.5%) in the receiver-operating characteristic curve were related to a poorer prognosis. Cases with a better prognosis showed significantly null/weak staining for VEGF (P < 0.001). Ki-67 expression of ≥ 5% was strongly correlated with a worse prognosis (P < 0.001). In the multivariate analysis, CD105 was the variable that most strongly correlated with prognosis. CONCLUSION: The IMVD cutoff values for the angiogenic markers CD105 and CD31, may be prognostic factors for GIST, in addition to VEGF and Ki67.

Comparative study of the different degrees of risk of gastrointestinal stromal tumor.

OBJECTIVE: To evaluate the applicability of the main categories of risk and morphological factors in the prognosis of gastrointestinal stromal tumors. METHODS: we retrospectively studied fifty-four cases of GIST, assessing the main prognostic factors of this neoplasis: risk levels, topography, size, mitotic index, necrosis, histological subtype and immunophenotype. We also verified their association and the reduction of overall survival. RESULTS: Univariate analysis showed that tumors with mitoses number greater than 5 per 50CGA (high-power fields), the presence of necrosis and a high risk for both the systems proposed by Fletcher and Miettinen had a significant association with reduced survival (p = 0.00001, 0.0056, 0.03 and 0.009, respectively). The remaining analyzed factors (size, histological subtype, topography and immunophenotype) had no such association. Multivariate analysis (Jacard index) showed that the Miettinen degree of risk was the one that best correlated with prognosis. CONCLUSION: the risk criteria of Fletcher and Miettinen are important in assessing the prognosis of patients with gastrointestinal stromal tumors, especially the latter, which adds to the mitotic index and the presence of tumor necrosis.

Comparative study of the different degrees of risk of gastrointestinal stromal tumor / Estudo comparativo dos diferentes graus de risco no tumor estromal gastrointestinal

OBJECTIVE: To evaluate the applicability of the main categories of risk and morphological factors in the prognosis of gastrointestinal stromal tumors. METHODS: we retrospectively studied fifty-four cases of GIST, assessing the main prognostic factors of this neoplasis: risk levels, topography, size, mitotic index, necrosis, histological subtype and immunophenotype. We also verified their association and the reduction of overall survival. RESULTS: Univariate analysis showed that tumors with mitoses number greater than 5 per 50CGA (high-power fields), the presence of necrosis and a high risk for both the systems proposed by Fletcher and Miettinen had a significant association with reduced survival (p = 0.00001, 0.0056, 0.03 and 0.009, respectively). The remaining analyzed factors (size, histological subtype, topography and immunophenotype) had no such association. Multivariate analysis (Jacard index) showed that the Miettinen degree of risk was the one that best correlated with prognosis. CONCLUSION: the risk criteria of Fletcher and Miettinen are important in assessing the prognosis of patients with gastrointestinal stromal tumors, especially the latter, which adds to the mitotic index and the presence of tumor necrosis.

OBJETIVO: Avaliar a aplicabilidade das principais categorias de risco e de fatores morfológicos no prognóstico tumor estromal gastrointestinal. MÉTODOS: cinquenta e quatro casos de GIST foram estudados retrospectivamente considerando-se os principais fatores prognósticos da neoplasia: graus de risco, topografia, tamanho, índice mitótico, necrose, subtipo histológico e imunofenótipo. Foi também verificada a sua associação e a redução da sobrevida global dos pacientes. RESULTADOS: a análise univariada mostrou que os tumores com número de mitoses maior que 5/50CGA (campos de grande aumento), a presença de necrose, de alto risco tanto para os sistemas propostos por Fletcher, quanto para Miettinen tiveram associação significativa com redução da sobrevida (p=0,00001, 0,0056, 0,03 e 0,009, respectivamente). Enquanto que os demais fatores analisados (tamanho, subtipo histológico, topografia e imunofenótipo) não tiveram tal associação. A análise multivariada (índice de Jacard) demonstrou que o grau de risco de Miettinen foi aquele que melhor se relacionou com o prognóstico. CONCLUSÃO: os critérios de risco de Fletcher e de Miettinen são importantes na avaliação do prognóstico de pacientes com tumor estromal gastrointestinal, principalmente este último, que se soma ao índice mitótico e a necrose tumoral.

As mucinas e o NCAM (CD56) na colangiocarcinogênese intra-hepática / Mucins and NCAM (CD56) in intrahepatic cholangiocarcinogenesis

Introduction: Cholangiocarcinoma is the second most common malignant neoplasm of the hepatobiliary system. During cholangiocarcinogenesis phenotypic changes occur in the ductal epithelium, including the expression of mucins (MUC). However, the evaluating studies of the expression of mucins in the different stages of cholangiocarcinogenesis are scarce. CD56 has also contributed in differentiating benign ductal proliferation and cholangiocarcinoma; however, its expression has not been evaluated in dysplastic epithelium of the bile duct yet. Objective: To assess immunohistochemical profile of (MUC) 1, 2, 5, 6, and CD56 in cholangiocarcinoma, pre-neoplastic and reactive lesions in the epithelium of intrahepatic bile ducts. Material and methods: Immunohistochemical expression of MUC 1, 2, 5, 6, and CD56 were studied for 11 cases of cholangiocarcinoma and 83 intrahepatic bile ducts (67 reactive and 16 dysplastic). Variables were considered significant when p < 0.05. Results: The expression of MUC1 occurred in about 90% of the cholangiocarcinomas, contrasting with the low frequency of positive cases in reactive and dysplastic bile ducts (p < 0.001). However, there was no statistically significant difference in the expression of MUC5, MUC6 and CD56 between the reactive or dysplastic lesions and cholangiocarcinoma. The anti-MUC2 antibody was negative in all cases. Conclusions: MUC1 contributed for the differential diagnosis between cholangiocarcinoma and pre-neoplastic and reactive/regenerative lesions of intrahepatic bile ducts, and it should compose the antibodies panel aiming at improvement of these differential diagnoses. In contrast, MUC2, MUC5, MUC6 and CD56 were not promising in differentiating all the phases of cholangiocarcinogenesis...

Introdução: O colangiocarcinoma é a segunda neoplasia maligna mais comum do sistema hepatobiliar. Durante a colangiocarcinogênese podem ocorrer alterações fenotípicas do epitélio ductal, incluindo a expressão de mucinas. Entretanto, os estudos que avaliam a expressão das mucinas nas diferentes etapas da colangiocarcinogênese são escassos. O CD56, apesar de contribuir na diferenciação entre as proliferações ductais benignas e o colangiocarcinoma, ainda não teve a sua expressão avaliada no epitélio displásico dos ductos biliares. Objetivos: Analisar o perfil das mucinas (MUC) 1, 2, 5, 6 e do CD56 no colangiocarcinoma, nas lesões pré-neoplásicas e reacionais de ductos biliares intra-hepáticos. Material e métodos: A expressão imuno-histoquímica da MUC 1, 2, 5, 6 e do CD56 foram avaliadas em 11 colangiocarcinomas e 83 ductos biliares intra-hepáticos (67 reativos e 16 displásicos). As variáveis foram consideradas como significativas quando p < 0,05. Resultados: A expressão da MUC1 ocorreu em cerca de 90% dos colangiocarcinomas, contrastando com a baixa frequência de casos positivos nos ductos biliares reativos ou displásicos (p < 0,001). Não houve diferença estatisticamente significativa na expressão de MUC5, MUC6 e CD56 entre as lesões reativas, displásicas e o colangiocarcinoma. O anticorpo anti-MUC2 foi negativo em todos os casos. Conclusão: A MUC1 contribuiu no diagnóstico diferencial entre o colangiocarcinoma e as lesões pré-neoplásicas e reacionais/regenerativas dos ductos biliares intra-hepáticos, e deve compor o painel de anticorpos a ser empregado visando o aprimorando destes diagnósticos diferenciais. Contrariamente, a MUC2, MUC5, MUC6 e o CD56 não se mostraram promissoras na diferen...

Microvascular density of regenerative nodule to small hepatocellular carcinoma by automated analysis using CD105 and CD34 immunoexpression.

BACKGROUND: Angiogenesis is a proliferative process resulting in the development of new blood vessels from existing endothelial cells and is considered crucial for tumor growth and metastasis. Tumor angiogenesis can be quantified by microvascular density (MVD), which is evaluated in highly vascularized tumor areas (hot spots) by immunohistochemical assays using CD34 and CD31 pan-endothelial antibodies. More recently, CD105 has been successfully used for some tumor types because it could discriminate neovascularization. The expression of CD34 and CD105 in hepatocellular carcinomas (HCC) and hepatic precancerous lesions has been reported-although the results for CD105 are controversial-but to the best our knowledge, CD105 has not been previously investigated in dysplastic nodules (DN). We investigated and compared MVD-CD34 and MVD-CD105 immunoexpression in tissues containing different stages of hepatocarcinogenesis, including DN. METHODS: A total of 31 regenerative nodules (RN), 26 DN and 25 small HCC from explants were used for immunohistochemical tests with CD34 and CD105 antibodies. Antibody expression was quantified by computerized image analysis measurement of MVD, areas containing highly positive endothelial cells within the nodules. RESULTS: The median MVD for CD34 was higher in HCC than in DN and RN (p < 0.01), and was higher in DN compared with RN (p = 0.033). In contrast, MVD with CD105 was higher in RN, and the difference was significant in RN and DN compared with HCC (p = 0.019 and p = 0.012, respectively). When MVD with CD34 and CD105 were compared within a single group, there was a significant predominance of CD105 in RN and DN (p < 0.01). In addition, MVD-C34 in HCC predominated compared with MVD-CD105, but the difference was not statistically significant (p = 0.128). CONCLUSIONS: This study identified a close relationship between CD105 and liver cirrhosis, and that CD34 antibody is a good endothelial marker for hepatic carcinogenesis. There was no difference between the use of CD105 and CD34 antibodies in preneoplastic lesions.

Nonalcoholic fatty liver disease: different classifications concordance and relationship between degrees of morphological features and spectrum of the disease.

The morphological features of nonalcoholic fatty liver disease (NAFLD) range from steatosis to nonalcoholic steatohepatitis (NASH) and cirrhosis. Liver biopsy remains the main tool for NASH diagnosis and many histological systems to diagnose and grade NAFLD were proposed. We evaluated the relationship among NAFLD activity score (NAS), histological diagnoses (non-NASH, possible NASH, and definite NASH), and histological algorithm proposed by Bedossa et al.; additionally the degrees of morphological features were semiquantified and correlated with non-NASH and NASH. Seventy-one liver biopsies were studied. The agreement among the three systems considering NASH and non-NASH was excellent (Κ = 0.96). Among the 22 biopsies with NAS 3-4, 72.7% showed to be NASH according to Bedossa's algorithm. The degree of steatosis, ballooning, lobular inflammation, and fibrosis stage were correlated with NASH (P < 0.001). Fibrosis stage 1 was also found in non-NASH. Over the spectrum of NAFLD, no association was observed between intensity of steatosis and fibrosis grade. The degrees of lobular inflammation showed association with fibrosis stage (P < 0.0001). In conclusion, there is agreement among different NAFLD classifications and NAS > 4 may be a better cutoff from which to consider NASH diagnosis; besides the highest degrees of steatosis, ballooning, inflammation, and fibrosis are associated with NASH.

Transforming growth factor α immunoreactivity. A study in hepatocellular carcinoma and in non-neoplastic liver tissue.

BACKGROUND: Transforming growth factor alpha (TGFα) is an important mitogen that binds to epidermal growth factor receptor and is associated with the development of several tumors. AIMS: Assessment of the immunoexpression of TGFα in hepatocellular carcinoma (HCC) and in non-neoplastic liver tissue and its relationship to morphological patterns of HCC. MATERIAL AND METHODS: The immunohistochemical expression of TGFα was studied in 47 cases of HCC (27 multinodular, 20 nodular lesions). Five lesions measured up to 5 cm and 15 lesions above 5 cm. Thirty-two cases were graded as I or II and 15 as III or IV. The non-neoplastic tissue was examined in 40 cases, of which 22 had cirrhosis. HBsAg and anti-HCV were positive in 5/38 and 15/37 patients, respectively. The statistical analysis for possible association of immunostaining of TGFα and pathological features was performed through chi-square test. RESULTS: TGFα was detected in 31.9% of the HCC and in 42.5% of the non-neoplastic. There was a statistically significant association between the expression of TGFα and cirrhosis (OR = 8.75, 95% CI = [1.93, 39.75]). The TGFα was detected more frequently in patients anti-HCV(+) than in those HBsAg(+). The immunoexpression of TGFα was not found related to tumor size or differentiation. In conclusion the TGFα is present in hepatocarcinogenesis in HBV negative patients. Further analysis is needed to examine the involvement of TGFα in the carcinogenesis associated with HCV and other possible agents. In addition, TGFα has an higher expression in hepatocyte regeneration and proliferation in cirrhotic livers than in HCC.

[Multiple focal nodular hyperplasia of the liver: mixed hyperplastic and adenomatous subtype]. / Hiperplasia nodular focal múltipla do fígado: subtipo misto hiperplásico/adenomatoso.

Focal Nodular Hyperplasia is a benign lesion of the liver, which usually presents with one or two localizations. We report the uncommon case of a 51-year-old female who presents with right upper quadrant pain that worsened in the previous month, without association with feeding. Four hepatic lesions were evidenced at Computerized tomography, the largest being of 8 cm in diameter, of atypical behavior. She was submitted to hepatic segmentectomy of the segment III. The pathologic diagnosis returned focal nodular hyperplasia mixed hyperplastic and adenomatous sub-type. The patient had a good postoperative evolution and is in ambulatory follow-up.

Expanded polytetrafluoroethylene in canine bile duct injury: a critical analysis.

PURPOSE: Analyze the morphological and structural outcomes of a patch of expanded polytetrafluoroethylene in the treatment of an iatrogenic injury of the common bile duct. METHODS: In Group 1 (Sham), 7 dogs underwent 3 laparotomies with intervals of 30 days between them. In Group 2, 10 dogs underwent transient common bile duct obstruction. After 30 days, this biliary occlusion was undone and a patch of expanded polytetrafluoroethylene replaced a fragment removed from the duct's wall. Thirty days after this last surgery, cholangiographic assessment of prosthesis patency and macro and microscopic evaluation of the biliary tract were performed. Daily clinical inspection completed the study outcomes. The Wilcoxon non-parametric test was used for statistical analysis. RESULTS: In all dogs enlargement of the biliary tree diameter was observed 30 and 60 days after the first surgical procedure. Partial adhesion of the patch to the common bile duct as a free luminal foreign body was found in 6 dogs. The prosthesis was completely integrated to surrounding tissue in the remaining four. CONCLUSION: Although a feasible option for the treatment of biliary duct iatrogenic lesions, the expanded polytetrafluoroethylene prosthesis must be used with caution considering the potential risks for complications.