366 research outputs found
GERD evaluation: Time for a new paradigm?
No full text© 2007 Lippincott Williams & Wilkins, Inc.Irvin M. Modlin, Peter Malfertheiner, Richard H. Hunt, David Armstrong, Gerald Holtmann, Eamon M. Quigley, Stuart J. Spechle
Molecular Genomic Assessment Using a Blood-based mRNA Signature (NETest) is Cost-effective and Predicts Neuroendocrine Tumor Recurrence With 94% Accuracy
No full textINTRODUCTION: Identification of residual disease after neuroendocrine tumor (NET) resection is critical for management. Post-surgery imaging is insensitive, expensive, and current biomarkers ineffective. We evaluated whether the NETest, a multigene liquid biopsy blood biomarker, correlated with surgical resection and could predict recurrence. METHODS: Multicenter evaluation of NET resections over 24 months (n = 103): 47 pancreas, 26 small bowel, 26 lung, 2 appendix, 1 duodenum, 1 stomach. Surgery: R0 (83), R1/R2 (20). One millilitre of blood was collected at D0 and posroperative day (POD) 30. Transcript quantification by polymerase chain reaction (normal: ≤20), CgA by NEOLISA (normal ≤108 ng/mL). Standard-of-care (SoC) follow-up costs were calculated and compared to POD30 NETest-stratification approach. Analyses: Wilcoxon-paired test, Chi-square test. D BIOMARKERS: NETest: 103 of 103 (100%)-positive, whereas 23 of 103 (22%) were CgA-positive (Chi-square = 78, P < 0.0001).In the R0 group, the NETest decreased 59 ± 28 to 26 ± 23 (P < 0.0001); 36% (30/83) remained elevated. No significant decrease was evident for CgA. In the R1/R2 group the NETest decreased but 100% remained elevated. CgA levels did not decrease.An elevated POD30 NETest was present in R0 and 25 (83%) developed radiological recurrences. Normal score R0 s (n = 53) did not develop recurrence (Chi-square = 56, P < 0.0001). Recurrence prediction was 94% accurate with the NETest. COST EVALUATION: Using the NETest to stratify postoperative imaging resulted in a cost-savings of 42%. CONCLUSION: NETest diagnosis is more accurate than CgA (100% vs 22%). Surgery significantly decreased NETest. An elevated POD30 NETest predicted recurrence with 94% accuracy and post-surgical POD30 NETest follow-up stratification decreased costs by 42%. CgA had no surgical utility. Further studies would define the accuracy and cost-effectiveness of the NETest in the detection of postoperative recurrent disease
Neuroendocrine Tumor Disease- An Evolving Landscape.
No full textGastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) represent a heterogeneous group of tumors arising from a variety of neuroendocrine cell types. The incidence and prevalence of GEP-NENs has markedly increased over the last three decades. Symptoms are often absent with early disease, or vague and non-specific even with advanced disease. Delayed diagnosis is thus common. Chromogranin A is the most commonly used bio marker but has substantial limitations. Identification of circulating tumor-derived mRNA transcripts presents a novel approach to predict development of metastases. The proliferative marker Ki-67\% is utilized for tumor grading and determination of therapy; it, however, has limitations. The development of a multidimensional prognostic nomogram may be valuable in predicting tumor behavior and guiding therapy. Identification of NENs that express somatostatin receptors allow for somatostatin receptor scintigraphy and PET imaging utilizing novel radiolabelled compounds. Complete surgical resection of limited disease or endoscopic ablation of small lesions localized in stomach or rectum can provide cure, however, the majority of GEP-NENs are metastatic (most frequently the liver and/or mesenteric lymph nodes) at diagnosis. Selected patients with metastatic disease may benefit from advanced surgical techniques including hepatic resection or liver transplantation. Somatostatin analogs are effective for symptomatic treatment and exhibit some degree of antiproliferative activity. With exception of streptozotozin in management pancreatic NENs there is little place for standard chemotherapy although new agents targeting either mTOR or angiogenic pathways pathways have shown efficacy in these lesions
Measurement of circulating transcripts and gene cluster analysis predicts and defines therapeutic efficacy of peptide receptor radionuclide therapy (PRRT) in neuroendocrine tumors
No full textBackground Peptide receptor radionuclide therapy (PRRT) is an effective method for treating neuroendocrine tumors (NETs). It is limited, however, in the prediction of individual tumor response and the precise and early identification of changes in tumor size. Currently, response prediction is based on somatostatin receptor expression and efficacy by morphological imaging and/or chromogranin A (CgA) measurement. The aim of this study was to assess the accuracy of circulating NET transcripts as a measure of PRRT efficacy, and moreover to identify prognostic gene clusters in pretreatment blood that could be interpolated with relevant clinical features in order to define a biological index for the tumor and a predictive quotient for PRRT efficacy. Methods NET patients (n = 54), M: F 37:17, median age 66, bronchial: n = 13, GEP-NET: n = 35, CUP: n = 6 were treated with Lu-177-based-PRRT (cumulative activity: 6.5-27.8 GBq, median 18.5). At baseline: 47/54 low-grade (G1/G2; bronchial typical/atypical), 31/49 (18)FDG positive and 39/54 progressive. Disease status was assessed by RECIST1.1. Transcripts were measured by real-time quantitative reverse transcription PCR (qRT-PCR) and multianalyte algorithmic analysis (NETest); CgA by enzyme-linked immunosorbent assay (ELISA). Gene cluster (GC) derivations: regulatory network, protein:protein interactome analyses. Statistical analyses: chi-square, non-parametric measurements, multiple regression, receiver operating characteristic and Kaplan-Meier survival. Results The disease control rate was 72 %. Median PFS was not achieved (follow-up: 1-33 months, median: 16). Only grading was associated with response (p < 0.01). At baseline, 94 % of patients were NETest-positive, while CgA was elevated in 59 %. NETest accurately (89 %, chi(2) = 27.4; p = 1.2 x 10(-7)) correlated with treatment response, while CgA was 24 % accurate. Gene cluster expression (growth-factor signalome and metabolome) had an AUC of 0.74 +/- 0.08 (z-statistic = 2.92, p < 0.004) for predicting response (76 % accuracy). Combination with grading reached an AUC: 0.90 +/- 0.07, irrespective of tumor origin. Circulating transcripts correlated accurately (94 %) with PRRT responders (SD+PR+CR; 97 %) vs. non-responders (91 %). Conclusions Blood NET transcript levels and the predictive quotient (circulating gene clusters+grading) accurately predicted PRRT efficacy. CgA was non-informative
Diagnosis and management of non-erosive reflux disease - The Vevey NERD Consensus Group
No full text<i>Background/Aims:</i> Although considerable information exists regarding gastroesophageal reflux disease with erosions, much less is known of non-erosive reflux disease (NERD), the dominant form of reflux disease in the developed world. <i>Methods:</i> An expert international group using the modified Delphi technique examined the quality of evidence and established levels of agreement relating to different aspects of NERD. Discussion focused on clinical presentation, assessment of clinical outcome, pathobiological mechanisms, and clinical strategies for diagnosis and management. <i>Results:</i> Consensus was reached on 85 specific statements. NERD was defined as a condition with reflux symptoms in the absence of mucosal lesions or breaks detected by conventional endoscopy, and without prior effective acid-suppressive therapy. Evidence supporting this diagnosis included: responsiveness to acid suppression therapy, abnormal reflux monitoring or the identification of specific novel endoscopic and histological findings. Functional heartburn was considered a separate entity not related to acid reflux. Proton pump inhibitors are the definitive therapy for NERD, with efficacy best evaluated by validated quality-of-life instruments. Adjunctive antacids or H<sub>2</sub> receptor antagonists are ineffective, surgery seldom indicated. <i>Conclusions:</i> Little is known of the pathobiology of NERD. Further elucidation of the mechanisms of mucosal and visceral hypersensitivity is required to improve NERD management.I.M. Modlin, R.H. Hunt, P. Malfertheiner, P. Moayyedi, E.M. Quigley, G.N.J. Tytgat, J. Tack, R.C. Heading, G. Holtman and S.F. Moss on behalf of the Vevey NERD Consensus Grou
A Nomogram to Assess Small-Intestinal Neuroendocrine Tumor (‘Carcinoid’) Survival
No full textNeuroendocrine tumors (NETs) are a heterogeneous group of cancers of which the commonest site is the small intestine (SI). Most information available to determine tumor behavior reflects univariate assessment of factors or is anecdotal or experience based. There currently exists no objective multivariate analysis of indices that defines SI NET prognosis. A key unmet need is the lack of a rigorous mathematical-based tool – a nomogram – for the assessment of parameters that define progress, determine prognosis and can guide therapy. Since prediction of NET behavior is a critical criterion in determining clinical strategy, we constructed a NET nomogram (Modlin Score) for prognosis prediction, patient group comparisons and a guide for stratification of treatment and surveillance. We used hazard ratio (HR), Cox analysis and Kaplan-Meier analysis of published data and the current Surveillance, Epidemiology and End Results (SEER) database (approx. 20,000 patients) to develop a nomogram from 15 variables demonstrated to provide significant multivariate HRs. These included age, gender, ethnicity, symptoms, urinary 5-hydroxyindoleacetic acid, plasma chromogranin A, liver function tests, tumor size, invasion, metastasis, histology, Ki-67 index, carcinoid heart disease and therapy (surgery or long-acting somatostatin analogs). Internal validation was assessed using 33 SI NET patients. A NET nomoscore (Modlin Score) was developed by HR weighting and stratification into low (<75), medium (75–95) and high risk (>95). This identified significant differences (p <0.03, Kaplan-Meier) in survival (15.5 ± 4.3, 9.7 ± 2.5 and 6.4 ± 1.1 years, respectively). The Modlin Score was significantly elevated (p <0.01) in deceased compared to alive patients. This nomogram represents an optimized construct based upon currently analyzable data, and application will facilitate accurate stratification for comparison in clinical trials. External validation and amplification by identification of additional indices, e.g. molecular biomarkers, are necessary. The development of a mathematically validated nomogram provides a platform for objective assessment of SI NET disease, a finite basis for precise prognostication and a tool to guide management strategy.</jats:p
Enrichment of rab11, a small GTP-binding protein, in gastric parietal cells
No full text Parietal cell secretion of acid requires the coordinated fusion of H(+)-K(+)-adenosinetriphosphatase (ATPase)-containing tubulovesicles with a secretory canalicular target membrane. We have previously reported the presence of rab2 on parietal cell tubulovesicles (L. H. Tang, S. A. Stoch, I. M. Modlin, and J. R. Goldenring. Biochem. J. 285: 715-719, 1992). Since 60% of the small GTP-binding protein sequences obtained from parietal cells were > 95% homologous with human rab11 (J. R. Goldenring, K. R. Shen, H. D. Vaughan, and I.M. Modlin. J. Biol. Chem. 268: 18419-18422, 1993), we sought to study rab11 in gastric parietal cells. A complete rab11 sequence was obtained, and the deduced amino acid sequence of rabbit rab11 was identical to that for human. Rab11 mRNA was present throughout the gastrointestinal mucosa. mRNA for both rab11 and rab2 were enriched in isolated parietal cells compared with chief cells. A polyclonal antiserum against rab11 labeled a single 25-kDa band in isolated parietal cells. Immunostaining of rat fundic tissue demonstrated prominent staining of parietal cells. Rab11 staining cosegregated with alpha-H(+)-K(+)-ATPase staining in enriched preparations of rabbit parietal cell tubulovesicles. These results suggest that rab11 is enriched in parietal cells and is associated with intracellular tubulovesicles. </jats:p
A multigenomic liquid biopsy biomarker for neuroendocrine tumor disease outperforms CgA and has surgical and clinical utility
No full textBackground: Biomarkers are key tools in cancer management. In neuroendocrine tumors (NETs), Chromogranin A (CgA) was considered acceptable as a biomarker. We compared the clinical efficacy of a multigenomic blood biomarker (NETest) to CgA over a 5-year period. Patients and methods: An observational, prospective, cross-sectional, multicenter, multinational, comparative cohort assessment. Cohort 1: NETest evaluation in NETs (n = 1684) and cancers, benign diseases, controls (n = 731). Cohort 2: (n = 1270): matched analysis of NETest/CgA in a sub-cohort of NETs (n = 922) versus other diseases and controls (n = 348). Disease status was assessed by response evaluation criteria in solid tumors (RECIST). NETest measurement: qPCR [upper limit of normal (ULN: 20)], CgA (EuroDiagnostica, ULN: 108 ng/ml). Statistics: Mann-Whitney U-test, AUROC, chi-square and McNemar' test. Results: Cohort 1: NETest diagnostic accuracy was 91% (P < 0.0001) and identified pheochromocytomas (98%), small intestine (94%), pancreas (91%), lung (88%), gastric (80%) and appendix (79%). NETest reflected grading: G1: 40 ± 1, G2 (50 ± 1) and G3 (52 ± 1). Locoregional disease levels were lower (38 ± 1) than metastatic (52 ± 1, P < 0.0001). NETest accurately stratified RECIST-assessed disease extent: no disease (21 ± 1), stable (43 ± 2), progressive (62 ± 2) (P < 0.0001). NETest concordance with imaging (CT/MRI/68Ga-SSA-PET) 91%. Presurgery, all NETs (n = 153) were positive (100%). After palliative R1/R2 surgery (n = 51) all (100%) remained elevated. After curative R0-surgery (n = 102), NETest levels were normal in 81 (70%) with no recurrence at 2 years. In the 31 (30%) with elevated levels, 25 (81%) recurred within 2 years. Cohort #2: NETest diagnostic accuracy was 87% and CgA 54% (P < 0.0001). NETest was more accurate than CgA for grading (chi-square = 7.7, OR = 18.5) and metastatic identification (chi-square = 180, OR = 8.4). NETest identified progressive disease (95%) versus CgA (57%, P < 0.0001). Imaging concordance for NETest was 91% versus CgA (46%) (P < 0.0001). Recurrence prediction after surgery was NETest-positive in >94% versus CgA 11%. Conclusion: NETest accurately diagnoses NETs and is an effective surrogate marker for imaging, grade, metastases and disease status compared to CgA. A multigenomic liquid biopsy is an accurate biomarker of NET disease
Error growth in poor ECMWF forecasts over the contiguous United States
No full textDue to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to [email protected], referencing the URI of the item.Includes bibliographical references.Successive improvements to the European Center for Medium-range Weather Forecasting model have resulted in improved forecast performance over the Contiguous United States (CONUS). While the overall performance of the model in this region was found to have improved during the period of the 1981-1990 winter seasons, the number of poor forecasts increased over this time. This study uses the Root Mean Square (RMS) error to measure the performance of 5-day 500 mb winter forecasts over the CONUS. Poor and good forecasts are defined in terms of the 10-year distribution of the RMS values between the 1981 and 1990 winter seasons. Subjective analysis of a subset of poor forecasts yielded no obvious patterns of error growth, location or propagation in the evolution of poor forecasts. A tendency is noted for in situ amplification of forecast errors. Additionally, successive forecasts verifying on the same day are found to have similar error patterns, with increased amplitudes at longer forecast lengths. This implies that the initial conditions are not a significant source of the error in poor forecasts. Empirical Orthogonal Function (EOF) analysis of error growth in time and space reveals significant differences between poor and good forecasts. Good forecasts are found to have the majority of RMS growth on day I while poor forecasts do not experience rapid error growth until days 3 and 4. For poor forecasts, the leading EOFs reveal a wave pattern down stream of the Rocky Mountains. This pattern evolves and propagates throughout the forecast period until it dominate the 5-day error field. No similar pattern is revealed in the error fields of good forecasts. This pattern suggests a dynamic link between the Rockies and the zonal wind, although no link with the 500 mb geostrophic wind could be established
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