Interdisciplinary Management of Cystic Neoplasms of the Pancreas

Cystic neoplasms of the pancreas are increasingly recognized due to the frequent use of abdominal imaging. It is reported that up to 20% of abdominal cross-sectional scans identify incidental asymptomatic pancreatic cysts. Proper characterization of pancreatic cystic neoplasms is important not only to recognize premalignant lesions that will require surgical resection, but also to allow nonoperative management of many cystic lesions that will not require resection with its inherent morbidity. Though reliable biomarkers are lacking, a wide spectrum of diagnostic modalities are available to evaluate pancreatic cystic neoplasms, including radiologic, endoscopic, laboratory, and pathologic analysis. An interdisciplinary approach to management of these lesions which incorporates recent, specialty-specific advances in the medical literature is herein suggested

Mass Spectrometry-Based Proteomics for Translational Research: A Technical Overview

Mass spectrometry-based investigation of clinical samples enables the high-throughput identification of protein biomarkers. We provide an overview of mass spectrometry-based proteomic techniques that are applicable to the investigation of clinical samples. We address sample collection, protein extraction and fractionation, mass spectrometry modalities, and quantitative proteomics. Finally, we examine the limitations and further potential of such technologies. Liquid chromatography fractionation coupled with tandem mass spectrometry is well suited to handle mixtures of hundreds or thousands of proteins. Mass spectrometry-based proteome elucidation can reveal potential biomarkers and aid in the development of hypotheses for downstream investigation of the molecular mechanisms of disease

A Proteomic Comparison of Formalin-Fixed Paraffin-Embedded Pancreatic Tissue from Autoimmune Pancreatitis, Chronic Pancreatitis, and Pancreatic Cancer

Content Formalin-fixed paraffin-embedded (FFPE) tissue is a standard for specimen preservation, and as such FFPE tissue banks are an untapped resource of histologically-characterized specimens for retrospective biomarker investigation for pancreatic disease. Objectives We use liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) to compare FFPE specimens from three different diseases of the exocrine pancreas. Design We investigated the proteomic profile of FFPE pancreatic tissue from 9 archived specimens that were histologically classified as: autoimmune pancreatitis (n=3), chronic pancreatitis (n=3), and pancreatic cancer (n=3), using LC-MS/MS. Setting This is a proteomic analysis experiment of FFPE pancreatic tissue in an academic center. Patients FFPE tissue specimens were provided by Dana-Farber/Harvard Cancer Center (Boston, MA, USA). Interventions FFPE tissue specimens were collected via routine surgical resection procedures. Main outcome measures We compared proteins identified from chronic pancreatitis, autoimmune pancreatitis, and pancreatic cancer FFPE pancreatic tissue. Results We identified 386 non-redundant proteins from 9 specimens. Following our filtering criteria, 73, 29, and 53 proteins were identified exclusively in autoimmune pancreatitis, chronic pancreatitis, and pancreatic cancer specimens, respectively. Conclusions We report that differentially-expressed proteins can be identified among FFPE tissues specimens originating from individuals with different histological diagnoses. These proteins merit further confirmation with a greater number of specimens and orthogonal validation, such as immunohistochemistry. The mass spectrometry-based methodology used herein has the potential to enhance diagnostic biomarker and therapeutic target discovery, further advancing pancreatic research.Image: Distribution of proteins among the AIP, CP, and PC cohorts

Subcellular fractionation enhances proteome coverage of pancreatic duct cells

Durante a década de sessenta, numa altura em que o mundo ia assistindo à consolidação triunfante dos independentismos anticoloniais, a ditadura portuguesa persistia em manter o seu domínio ultramarino. Apesar de educados numa certa "mística imperial" e limitados nos seus direitos de expressão e associação, alguns sectores da sociedade, essencialmente enraizados nos territórios estudantis, foram construindo um horizonte de intervenção fortemente crítico do colonialismo do regime. Este texto pretende caracterizar a prática e o discurso de uma destas áreas, no caso a pulverizada corrente maoísta, contextualizando previamente a ideia de violência nas leituras sobre os 'longos anos sessenta' e a especificidade do maoísmo emergente nesse tempo

The Utility of the Systemic Inflammatory Respsonse [Response] Syndrome Score on Admission in Children With Acute Pancreatitis

OBJECTIVES: Pediatric patients with acute pancreatitis (AP) may meet criteria at admission for the systemic inflammatory response syndrome (SIRS). Early SIRS in adults with AP is associated with severe disease. Our aim was to evaluate the importance of SIRS in children presenting with AP on various outcomes. METHODS: This is a retrospective cohort study of children hospitalized with AP at Boston Children\u27s Hospital in 2010. Increased length of stay (LOS) and/or admission to the intensive care unit (ICU) served as the primary outcomes. Statistical analyses of measures studied included the presence of SIRS, demographic, and clinical information present on admission. RESULTS: Fifty encounters, in which AP was the primary admitting diagnosis, were documented. Patients had a median LOS of 4.5 (interquartile range, 2-9) days. Systemic inflammatory response syndrome was present in 22 (44%) of 50 patients at admission. Systemic inflammatory response syndrome at admission was an independent predictor of increased LOS (odds ratio, 7.99; P = 0.045) as well as admission to the ICU (odds ratio, 12.06; P = 0.027). CONCLUSIONS: The presence of SIRS criteria on admission serves as a useful and easy-to-calculate predictor of increased LOS and admission to ICU in children with AP

Urinary 1H-NMR Metabolomics Can Distinguish Pancreatitis Patients from Healthy Controls

Context The characterization of the urinary metabolome may yield biomarkers indicative of pancreatitis. Objectives We establish a non-invasive technique to compare urinary metabolic profiles in patients with acute and chronic pancreatitis to healthy controls. Methods Urine was obtained from healthy controls (HC, n=5), inpatients with mild acute pancreatitis (AP, n=5), and outpatients with chronic pancreatitis (CP, n=5). Proton nuclear magnetic resonance spectra were obtained for each sample. Metabolites were identified and quantified in each spectrum; resulting concentrations were normalized to account for differences in dilution among samples. Kruskal-Wallis test, post-hoc Mann-Whitney U tests, and principal component analysis were performed to identify metabolites that discriminate healthy controls, acute pancreatitis, and chronic pancreatitis. Results Sixty metabolites were identified and quantified; five were found to differ significantly (P<0.05) among the three groups. Of these, citrate and adenosine remained significant after validation by random permutation. Principal component analysis demonstrated that healthy control urine samples can be differentiated from patients with chronic pancreatitis or acute pancreatitis; chronic pancreatitis patients could not be distinguished from acute pancreatitis patients. Conclusions This metabolomic investigation demonstrates that this non-invasive technique offers insight into the metabolic states of pancreatitis. Although the identified metabolites cannot conclusively be defined as biomarkers of disease, future studies will validate our findings in larger patient cohorts.Image: Boxplots of two significant metabolites

Incidence and clinical sequelae of portal and hepatic venous thrombosis following percutaneous cryoablation of liver tumors.

PURPOSE: To assess the incidence and sequelae of portal and hepatic venous thrombosis after percutaneous cryoablation of hepatic tumors. METHODS: From November 1998 through December 2010, 223 hepatic tumors were cryoablated during 170 ablation procedures in 135 patients. 24-h post-procedure MR images were reviewed retrospectively by two abdominal radiologists in consensus to identify tumor ablations that developed one or more new portal or hepatic venous thromboses in or outside the ablation zone. On follow-up MRI and CT examinations the outcomes of thromboses were classified as resolved, partially recanalized, persistent, or propagated. RESULTS: Venous thrombosis developed in association with 54 (24%) of 223 tumor ablations treated during 53 (31%) ablation procedures in 39 (28.8%) patients (15 women, 24 men; age range 40-82 years, mean 59 years). Of these 54 thromboses, 49 (91%) were located in portal vein branches, four (7%) in both portal and hepatic vein branches, and one (2%) in a hepatic vein branch. Thrombosed veins were outside but abutted the ablation zone in 36 (66.7%), and within it in 18 (33.3%). On follow-up imaging (n = 49), thrombi resolved in 29 (59%), partially recanalized in two (4%), persisted in 18 (37%) and propagated from sub-segmental or segmental branches to the left or right portal branches in five (10%). No thrombus propagated to the main portal vein or inferior vena cava. CONCLUSION: Portal and hepatic vein branch thromboses are common in small branches following percutaneous cryoablation of hepatic tumors and most resolve spontaneously without sequelae

Analysis of Endoscopic Pancreatic Function Test (ePFT)-Collected Pancreatic Fluid Proteins Precipitated Via Ultracentrifugation

Context We have shown previously that trichloroacetic acid precipitation is an effective method of protein extraction from pancreatic fluid for downstream biomarker discovery, compared to other common extraction methods tested. Objective We aim to assess the utility of ultracentrifugation as an alternative method of protein extraction from pancreatic fluid. Design Proteins extracted from trichloroacetic acid- and ultracentrifugation-precipitated pancreatic fluid were identified using mass spectrometry techniques (in-gel tryptic digestion followed by liquid chromatography-tandem mass spectrometry; GeLC-MS/MS). Data were analyzed using Proteome Discoverer and Scaffold 3. Setting This is a proteomic analysis experiment of endoscopically collected fluid in an academic center. Patients The study population included adult patients referred to the Center for Pancreatic Disease at Brigham and Women’s Hospital, Boston, MA, USA for the evaluation of abdominal pain and gastrointestinal symptoms. Interventions Secretin-stimulated pancreatic fluid was collected as standard of care for the evaluation of abdominal pain and gastrointestinal symptoms. Main outcome measures We compared proteins identified via standard trichloroacetic acid precipitation and this alternative ultracentrifugation strategy. Results A subset of pancreatic fluid proteins was identified via the ultracentrifugation method. Of these proteins, similar numbers were obtained from fully tryptic or semi-tryptic database searching. Proteins identified in the ultracentrifugation-precipitated samples included previously identified biomarker candidates of chronic pancreatitis. Conclusions This alternative ultracentrifugation strategy requires less time and fewer handling procedures than standard trichloroacetic acid precipitation, at the expense of higher sample volume. As such, this method is well suited for targeted assays (i.e., dot blotting or targeted mass spectrometry) if the protein of interest is among those readily identified by ultracentrifugation-promoted precipitation.Image: SDS-PAGE protein fractionation

Utility of Commercial DNA Analysis in Detecting Malignancy within Pancreatic Cysts

Context Pancreatic cysts raise concern because of their malignant potential. Our aims were to assess accuracy of DNA analysis in detecting malignant pancreatic cysts at EUS-FNA and to determine whether DNA analysis added to imaging and cyst fluid studies enhanced International Association of Pancreatology (IAP) guidelines for resection of pancreatic cysts. Methods This is a retrospective study including pancreatic cysts undergoing EUS-FNA and DNA analysis with k-ras and loss of heterozygosity testing. Diagnostic models of 2006 and 2012 IAP guidelines, DNA analysis alone, and DNA combined with 2012 IAP guidelines were developed, and area under receiver operator characteristic curves (AUC) compared to determine the added value of DNA for detecting malignant cysts at the time of EUS-FNA. Results Two-hundreds and fifty-seven patients were included with 8 (3.1%) malignant cysts. Solid component (P<0.001), main pancreatic duct dilation (P=0.012), suspicious or malignant cytology (P=0.001), and high DNA quantity (P<0.001) were associated with malignancy. Concurrent high amplitude k-ras with loss of heterozygosity mutations was highly specific (98.4%) though insensitive (12.5%) for malignancy. The 2012 IAP guideline (AUC=0.87; 95% CI: 0.82-0.91) was superior to 2006 IAP guideline (AUC=0.54; 95% CI: 0.47-0.60) and DNA analysis alone (AUC=0.60; 95% CI: 0.53-0.66) for detecting malignant cysts (P=0.004 and P=0.002, respectively). Addition of DNA did not improve performance of the 2012 IAP guideline (AUC=0.84; 95% CI: 0.79-0.88). Conclusions Commercial DNA analysis does not add useful information beyond imaging and cytology for detection of malignant pancreatic cysts. The 2012 IAP guideline better predicted malignant cysts than the 2006 IAP guideline.Image: DNA double heli

Differentiating Branch Duct and Mixed IPMN in Endoscopically Collected Pancreatic Cyst Fluid via Cytokine Analysis

Background. Differentiating branch duct from mixed intraductal papillary mucinous neoplasm (BD-IPMN) is problematic, but clinically important as mixed IPMNs are managed surgically, while some BD-IPMN may be followed. Inflammatory mediator proteins (IMPs) have been implicated in acute and chronic inflammatory and malignant pancreatic diseases. Aim. To compare IMP profile of pancreatic cyst fluid collected endoscopically from BD-IPMN and mixed IPMN. Methods. Pancreatic cyst fluid from ten patients (5 BD-IPMN and 5 mixed IPMN) was collected by endoscopic ultrasound-guided fine needle aspiration or endoscopic retrograde cholangiopancreatography. Concentrations of 89 IMPs in these samples were determined using a multiplexed bead-based microarray protein assay and compared between BD-IPMN and mixed IPMN. Results. Eighty-six of 89 IMPs were detected in at least one of the 10 samples. Fourteen IMPs were detected only in mixed IPMN, while none were only in BD-IPMN. Of these, TGF-β1 was most prevalent, present in 3 of 5 mixed IPMNs. Seventy-two IMPs were detected in both BD-IPMN and mixed IPMNs. Of these, only G-CSF (P<0.05) was present in higher concentrations in mixed IPMNs. Conclusion. TGF-β1 and G-CSF detected in endoscopically collected pancreatic cyst fluid are potential diagnostic biomarkers capable of distinguishing mixed IPMN from BD-IPMN