Eva C. Vaquero

Impact of Wide-Angle, High-Definition Endoscopy in the Diagnosis of Colorectal Neoplasia: A Randomized Controlled Trial

BACKGROUND & AIMS It is essential to optimize standard colonoscopy technique to be able to increase polyp detection. We sought to compare the performance of colonoscopy using a high-definition, wide-angle endoscope (HDE) versus a standard colonoscope (SC) for the detection of colorectal neoplasia. PATIENTS AND METHODS All consecutive consenting adult patients referred from primary care centers were included and randomly assigned at a 1:1 ratio to undergo HDE or SC. Times to reach and withdraw from the cecum were measured. Morphology, size, location, and pathologic diagnosis of each polyp were recorded. Sample size calculation resulted in a total of 682 patients needed. RESULTS A total of 693 consecutive patients fulfilled all inclusion criteria (73 excluded owing to insufficient bowel preparation). Each arm included 310 patients with no baseline characteristic differences. Time to reach the cecum was slightly superior for SC (8.9 +/- 4.8 minutes vs 8.2 +/- 4.5 minutes; P = .055). Pathology examination was feasible in 418 lesions (272 adenomas, 109 hyperplastic polyps, and 37 inflammatory lesions). Both techniques detected a similar number and type of lesions, and there were no differences in the distribution along the colon, in the degree of dysplasia, or morphology of adenomas. The per-patient basis analyses demonstrated that there were no differences between the 2 arms of the study in the detection rates of polyps (SC, 0.84 +/- 1.59; HDE, 0.83 +/- 1.30), adenomas (0.45 +/- 1.07 vs 0.43 +/- 0.87), small adenomas (0.22 +/- 0.71 vs 0.28 +/- 0.78), flat adenomas (0.30 +/- 0.91 vs 0.21 +/- 0.63), or hyperplastic polyps (0.16 +/- 0.50 vs 0.18 +/- 0.54). CONCLUSION HDE did not detect significantly more colorectal neoplasia than SC.

Serous cystic neoplasm of the pancreas: a multinational study of 2622 patients under the auspices of the International Association of Pancreatology and European Pancreatic Club (European Study Group on Cystic Tumors of the Pancreas)

Objectives Serous cystic neoplasm (SCN) is a cystic neoplasm of the pancreas whose natural history is poorly known. The purpose of the study was to attempt to describe the natural history of SCN, including the specific mortality. Design Retrospective multinational study including SCN diagnosed between 1990 and 2014. Results 2622 patients were included. Seventy-four per cent were women, and median age at diagnosis was 58 years (16–99). Patients presented with non-specific abdominal pain (27%), pancreaticobiliary symptoms (9%), diabetes mellitus (5%), other symptoms (4%) and/or were asymptomatic (61%). Fifty-two per cent of patients were operated on during the first year after diagnosis (median size: 40 mm (2–200)), 9% had resection beyond 1 year of follow-up (3 years (1–20), size at diagnosis: 25 mm (4–140)) and 39% had no surgery (3.6 years (1–23), 25.5 mm (1–200)). Surgical indications were (not exclusive) uncertain diagnosis (60%), symptoms (23%), size increase (12%), large size (6%) and adjacent organ compression (5%). In patients followed beyond 1 year (n=1271), size increased in 37% (growth rate: 4 mm/year), was stable in 57% and decreased in 6%. Three serous cystadenocarcinomas were recorded. Postoperative mortality was 0.6% (n=10), and SCNs related mortality was 0.1% (n=1). Conclusions After a 3-year follow-up, clinical relevant symptoms occurred in a very small proportion of patients and size slowly increased in less than half. Surgical treatment should be proposed only for diagnosis remaining uncertain after complete workup, significant and related symptoms or exceptionally when exists concern with malignancy. This study supports an initial conservative management in the majority of patients with SCN. Trial registration number IRB 00006477.

Myofibroblast proliferation, fibrosis, and defective pancreatic repair induced by cyclosporin in rats

BACKGROUND Full recovery is always achieved after caerulein induced pancreatitis. Cyclosporin stimulates transforming growth factor β (TGF-β) and may interfere with pancreatic regeneration. AIM To investigate the effects of cyclosporin after caerulein induced pancreatitis or after caerulein injury. METHODS Protocol A: rats received cyclosporin daily (20 mg/kg) and caerulein pancreatitis was induced on days 2 and 8. Protocol B: six courses of caerulein pancreatitis were induced at weekly intervals. Cyclosporin was administered on induction and the day before. Rats recovered for two weeks before being killed. Control groups received saline, cyclosporin, or caerulein alone. RESULTS Protocol A: plasma TGF-β1 and tissue collagenase rose after pancreatitis but decreased towards baseline values on day 15, matching a low collagen content. Morphology disclosed minimal inflammatory infiltration and some interstitial cells immunoreactive for smooth muscle α-actin (SMA). TGF-β1 increased, and remained high in cyclosporin treated groups (cyclosporin alone and cyclosporin plus caerulein). Rats treated with cyclosporin and caerulein showed severe pancreatic weight reduction, abundant inflammatory infiltrates, increased SMA immunoreactive interstitial cells, high collagen content, and delayed collagenase response. No SMA immunoreactive cells were detected in normal rats. Cyclosporin alone also increased SMA immunoreactive cells, despite the absence of inflammatory infiltration and fairly conserved pancreatic structure. Protocol B: the combined pulse treatment induced appreciable collagen deposition and resulted in a smaller pancreas than controls. Morphological examination showed atrophy, fibrosis, fibroblast proliferation, and mononuclear infiltrates. CONCLUSION Cyclosporin greatly distorts pancreatic repair, transforming caerulein induced pancreatitis into a fibrotic chronic-like disease. The mechanism involves TGF-β, myofibroblasts, and defective collagenase activation.

The Spanish Pancreatic Club's recommendations for the diagnosis and treatment of chronic pancreatitis: part 2 (treatment).

Chronic pancreatitis (CP) is a complex disease with a wide range of clinical manifestations. This range comprises from asymptomatic patients to patients with disabling symptoms or complications. The management of CP is frequently different between geographic areas and even medical centers. This is due to the paucity of high quality studies and clinical practice guidelines regarding its diagnosis and treatment. The aim of the Spanish Pancreatic Club was to give current evidence-based recommendations for the management of CP. Two coordinators chose a multidisciplinary panel of 24 experts on this disease. These experts were selected according to clinical and research experience in CP. A list of questions was made and two experts reviewed each question. A draft was later produced and discussed with the entire panel of experts in a face-to-face meeting. The level of evidence was based on the ratings given by the Oxford Centre for Evidence-Based Medicine. In the second part of the consensus, recommendations were given regarding the management of pain, pseudocysts, duodenal and biliary stenosis, pancreatic fistula and ascites, left portal hypertension, diabetes mellitus, exocrine pancreatic insufficiency, and nutritional support in CP.

Gene expression dynamics after murine pancreatitis unveils novel roles for Hnf1α in acinar cell homeostasis

Objectives During pancreatitis, specific transcriptional programmes govern functional regeneration after injury. The objective of this study was to analyse the dynamic regulation of pancreatic genes and the role of transcriptional regulators during recovery from pancreatitis. Design Wild-type and genetically modified mice (Hnf1α−/− and Ptf1a+/−) were used. After caerulein or l-arginine induced pancreatitis, blood or pancreata were processed for enzymatic assays, ELISA, histology, immunohistochemistry, western blotting and quantitative reverse transcriptase-PCR. Nr5a2 promoter reporter and chromatin immunoprecipitation assays for Hnf1α were also performed. Results After caerulein pancreatic injury, expression of acinar and endocrine genes rapidly decreased, but eventually recovered, depicting distinct cell-type-specific patterns. Pdx1 and Hnf1α mRNAs underwent marked downregulation, matching endocrine/exocrine gene expression profiles. Ptf1a, Pdx1 and Hnf1α protein levels were also reduced and recovered gradually. These changes were associated with transient impairment of exocrine and endocrine function, including abnormal glucose tolerance. On l-arginine pancreatitis, changes in Ptf1a, Pdx1 and Hnf1α gene and protein expression were recapitulated. Reduced Hnf1α and Ptf1a levels after pancreatitis coincided with increased acinar cell proliferation, both in Hnf1α−/− and Ptf1a+/− mice. Moreover, Hnf1α−/− mice had reduced Ptf1a protein as well as transcripts for Ptf1a and digestive enzymes. Dispersed acini from Hnf1α−/− mice showed suboptimal secretory responses to caerulein. Bioinformatics analysis did not support a role for Hnf1α as a direct regulator of digestive enzyme genes. Instead, it was found that Hnf1α binds to, and regulates, the promoter of Nr5a2, coding an orphan nuclear receptor that regulates acinar gene expression. Conclusions Dynamic changes in gene expression occur on pancreatitis induction, determining altered exocrine and endocrine function. This analysis uncovers roles for Hnf1α in the regulation of acinar cell determination and function. This effect may be mediated, in part, through direct regulation of Nr5a2.

Ethanol Feeding Aggravates Morphological and Biochemical Parameters in Experimental Chronic Pancreatitis

Background and Aims: Instillation of trinitrobenzene sulfonic acid (TNBS) into the rat pancreatic ducts induces morphological changes resembling human chronic pancreatitis. In humans, alcoholism is commonly associated with chronic pancreatitis, but ethanol feeding fails to induce pancreatitis in experimental animals. We hypothesized that ethanol would manifest its pathogenetic effects on a duct-injured pancreas. Methods: Chronic pancreatitis was induced in rats by instillation of TNBS into pancreatic ducts. Thereafter, rats were fed a normal chow diet with or without ethanol supplementation. Control rats received vehicle and a normal diet. A separate group of vehicle-treated rats were also fed with ethanol. At 2 and 4 weeks pancreata were excised and processed for morphological examination or for biochemical assays. From crude homogenates, protein and hydroxyproline were quantified. After sonication, homogenates were also assayed for amylase and DNA. An oral glucose tolerance test was performed on the fourth week. Results: TNBS induced chronic fibrogenic pancreatitis that was associated with a reduction in pancreatic weight, DNA, protein and amylase as compared to control rats. Ethanol feeding to TNBS-treated animals slowed weight gain, increased fasting glucose and impaired glucose tolerance test. Larger areas of gland atrophy were observed with a striking disruption of the normal architecture of the islets. Ethanol accelerated pancreatic involution and collagen deposition as measured by total amylase, protein, DNA and hydroxyproline content. Conclusions: In TNBS chronic pancreatitis, active fibrogenesis is associated with progressive atrophy of glandular elements. Morphological and biochemical parameters are aggravated by sustained ethanol intake.

The Spanish Pancreatic Club recommendations for the diagnosis and treatment of chronic pancreatitis: Part 1 (diagnosis)

Chronic pancreatitis (CP) is a relatively uncommon, complex and heterogeneous disease. The absence of a gold standard applicable to the initial phases of CP makes its early diagnosis difficult. Some of its complications, particularly chronic pain, can be difficult to manage. There is much variability in the diagnosis and treatment of CP and its complications amongst centers and professionals. The Spanish Pancreatic Club has developed a consensus on the management of CP. Two coordinators chose a multidisciplinary panel of 24 experts on this disease. A list of questions was drafted, and two experts reviewed each question. Then, a draft was produced and shared with the entire panel of experts and discussed in a face-to-face meeting. This first part of the consensus addresses the diagnosis of CP and its complications.

Evidence-based Guidelines for the Management of Exocrine Pancreatic Insufficiency After Pancreatic Surgery

Objective: To provide evidence-based recommendations for the management of exocrine pancreatic insufficiency (EPI) after pancreatic surgery. Background: EPI is a common complication after pancreatic surgery but there is certain confusion about its frequency, optimal methods of diagnosis, and when and how to treat these patients. Methods: Eighteen multidisciplinary reviewers performed a systematic review on 10 predefined questions following the GRADE methodology. Six external expert referees reviewed the retrieved information. Members from Spanish Association of Pancreatology were invited to suggest modifications and voted for the quantification of agreement. Results: These guidelines analyze the definition of EPI after pancreatic surgery, (one question), its frequency after specific techniques and underlying disease (four questions), its clinical consequences (one question), diagnosis (one question), when and how to treat postsurgical EPI (two questions) and its impact on the quality of life (one question). Eleven statements answering those 10 questions were provided: one (9.1%) was rated as a strong recommendation according to GRADE, three (27.3%) as moderate and seven (63.6%) as weak. All statements had strong agreement. Conclusions: EPI is a frequent but under-recognized complication of pancreatic surgery. These guidelines provide evidence-based recommendations for the definition, diagnosis, and management of EPI after pancreatic surgery.

Assessment of the protective effects of oral tocotrienols in arginine chronic-like pancreatitis

Tocotrienols exhibit anti-inflammatory properties over macrophages and promote cytotoxicity in activated pancreatic stellate cells, suggesting that they may limit chronic pancreatitis progression. We aimed to quantitate the effect of oral tocotrienols on a rat model of chronic pancreatic injury. Chronic-like pancreatitis was induced by repeated arginine pancreatitis. Palm oil tocotrienol-rich fraction (TRF) was given by gavage before and after pancreatitis inductions. Amylase and hydroxyproline were determined in pancreatic homogenates; collagen, fibronectin, α-smooth muscle actin (SMA), glial fibrillary acidic protein (GFAP), and phosphorylated Smad3 were assessed by Western blotting. Transforming growth factor (TGF)-β1 was measured in plasma. Morphological assessment included light microscopy, fibrosis area fraction, and collagen network fractal analysis. Arginine pancreatitis induced pancreatic atrophy and increased hydroxyproline that ameliorated after TRF. Arginine increased TGF-β1 (185 ± 40 vs. 15 ± 2 ng/ml; P <0.01) that was blunted by TRF (53 ± 19; P < 0.01). TRF reduced protease and Smad3 activation, collagen, and fibronectin. α-SMA increased and GFAP diminished in arginine pancreatitis, consistent with long-term stellate cell activation, and TRF reverted these changes to basal. Arginine pancreatitis increased fibrosis area fraction (4.5 ± 0.3% vs. 0.2 ± 0.2%), collagen network complexity (fractal dimension 1.52 ± 0.03 vs. 1.42 ± 0.01; P < 0.001), and inhomogeneity (lacunarity 0.63 ± 0.03 vs. 0.40 ± 0.02; P < 0.001), which were all reduced by TRF (1.3 ± 0.4%, 1.43 ± 0.02%, and 0.51 ± 0.03%, respectively; P < 0.01). Best correlation coefficients were obtained when comparing fibrosis area fraction with lacunarity (r = 0.88) and both parameters with pancreatic weight (r = -0.91 and -0.79, respectively). TRF administered only before pancreatitis best, but not fully, recapitulated the beneficial effects of TRF. Tocotrienols improve quantitative measures of chronic pancreatic damage. They may be of benefit in human chronic pancreatitis.

Tocotrienols Balancing the Mitochondrial Crosstalk Between Apoptosis and Autophagy

Tocotrienols are a group of natural vitamin E compounds with patent antitumoral effects, mostly based on their ability to induce apoptosis in cancer cells. In activated pancreatic stellate cells (PSCs) we have determined that tocotrienols elicit a dramatic mitochondrial destabilization followed by initiation of non-necrotic forms of programmed cell death, namely apoptosis and autophagy. PSCs are the main cell type involved in the generation of pancreatic fibrosis, and their removal is critical to limit the fibrogenic process. Noteworthy, tocotrienol death-promoting actions are exclusively directed to activated PSCs, but not to their quiescent counterparts nor to terminally differentiated acinar cells. Here, we hypothesize that the transformed phenotype of PSCs may include “activated” mitochondria, which can be used by tocotrienols to trigger autophagic and apoptotic signaling. We propose that mitochondria are the cornerstone of cell sensitivity to tocotrienols, and suggest possible mechanisms, that may be interconnected, on how tocotrienols may govern mitochondrial death pathways. Addendum to: Tocotrienols Induce Apoptosis and Autophagy in Rat Pancreatic Stellate Cells through the Mitochondrial Death Pathway M. Rickmann, E.C. Vaquero, J.R. Malagelada and X. Molero Gastroenterology 2007; 132:2518-32