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Screening for pancreatic cancer in high-risk individuals
Full text linkAbstract
Introduction: Surveillance programs on high-risk individuals (HRIs) can detect premalignant lesions or early pancreatic cancer (PC). We report the results of the first screening round of the Italian multicenter program supported by the Italian Association for the study of the Pancreas (AISP).
Methods: The multicenter surveillance program included asymptomatic HRIs with familial (FPC) or genetic frailty (GS: BRCA1/2, p16/CDKN2A, STK11/LKB1 and PRSS1) predisposition to PC. The surveillance program included at least an annual magnetic resonance cholangiopancreatography (MRCP). Endoscopic ultrasound (EUS) was proposed to patients who refused or could not be submitted to MRCP.
Results: One-hundreds eighty-seven HRIs underwent a first-round screening examination with MRCP (174;93.1%) or EUS (13;6.9%) from September 2015 to March 2018.The mean age was 51 years (range 21-80).One-hundreds sixty-five (88.2%) FPC and 22 (11.8%) GF HRIs were included. MRCP detected 27 (21.9%) presumed branch-duct intraductal papillary mucinous neoplasms (IPMN), 1 invasive carcinoma/IPMN and one low-grade mixed-type IPMN, respectively. EUS detected 4 PC (2.1%): 1 was resected, 1 was found locally advanced intraoperatively and 2 were metastatic. Age>50 (OR 3.3, 95%CI 1.4-8), smoking habit (OR 2.8, 95%CI 1.1-7.5), and having >2 relatives with PC (OR 2.7, 95%CI 1.1-6.4) were independently associated with detection of pre-malignant and malignant lesions. The diagnostic yield for MRCP/EUS was 20.3% for cystic lesions. The overall rate of surgery was 2.6% with nil mortality.
Discussion: The rate of malignancies found in this cohort was high (2.6%). According to the International Cancer of the Pancreas Screening Consortium the screening goal achievement was high (1%).ABSTRACT Background: Data on surveillance for pancreatic ductal adenocarcinoma (PDAC) in high-risk individuals (HRIs) with “familiar pancreatic cancer” (FPC) and specific syndromes are limited and heterogeneous.
Objective: We conducted a systematic review and meta-analysis of PDAC surveillance studies.
Methods: Prevalence of solid/cystic pancreatic lesions and of lesions considered a successful target of surveillance (proven resectable PDAC and high-grade precursors) was pooled across studies. The rate of lesions diagnosed by EUS/MRI and across different HRIs groups were calculated.
Results: Sixteen studies incorporating 1588 HRIs included. The pooled prevalence of pancreatic solid and cystic lesions was 5.8% and 20.2%, respectively. The pooled prevalence of patients with lesions considered a successful target of surveillance was 3.3%, being similar with EUS or MRI and varied across subgroups, being 3% in FPC, 4% in hereditary pancreatitis, 5% in familiar
melanoma, 6.3% in hereditary breast/ovarian cancer and 12.2% in Peutz Jeghers. The pooled estimate rate of lesions considered a successful target of surveillance during follow-up was 5/1000 person-years.
Conclusion: Surveillance programs identifiy successful target lesions in 3.3% of HRIs with similar yield of EUS and MRI and an annual risk of 0.5%. A higher rate of target lesions was reported in HRIs with specific DNA mutations.Background and Aims: Different pancreatic abnormalities (e.g. chronic pancreatitis like features, cystic lesions, solid lesions) have been reported in in high-risk individuals (HRIs) with “familiar pancreatic cancer” (FPC) and specific syndromes undergoing surveillance protocols for pancreatic ductal adenocarcinoma (PDAC). Previous studies compared pancreatic parenchymal alterations detected by endoscopic ultrasonography (EUS) in HRIs to those seen in controls reporting that abnormal changes occur more frequently in HRIs than in controls. However, while magnetic resonance imaging (MRI) with Magnetic Resonance Cholangiopancreatography (MRCP) is the most frequently employed method for HRI surveillance, no studies compared the rate of abnormal pancreatic finding in HRIs investigated by MRI/MRCP to those seen in controls. We therefore conducted a case-control study enrolling HRIs who underwent surveillance with MRI/MRCP and controls without pancreatic disorders to compare the rate and type of pancreatic abnormalities.
Methods: A single-centre case control study was conducted. Cases were HRIs meeting the CAPS criteria who underwent surveillance for the risk of pancreatic cancer and controls were consecutive patients undergoing MRI/MRCP for benign biliary disease without history of pancreatic disorders.
The rate of pancreatic findings was compared with Fisher extact test and logistic regression analysis was performed to examine factors associated with pancreatic findings.
Results: 28 HRIs and 26 controls were included in the study. HRIs were subjects belonging to FPC families (70%), Peutz-Jeghers syndrome (14%), familial atypical multiple mole melanoma syndrome (7%) , BRCA1/2 mutation carriers (7%) . Cases and controls did not differ in terms of sex distribution and age (male 50% vs 53.6, p=0.5; mean age 55.6 vs 59.6 years p = 0.1). The overall rate of any pancreatic abnormality was similar between cases and controls (64.3% vs 53.8%; p=0.58) and parenchymal atrophy was the most common abnormal finding (32% vs 38%, p= 0.8). Branch-duct IPMNs were diagnosed in 25% of cases and 23% of controls (p= 1)(mean diameter 6.4 vs 5 mm respectively). Notably, however, at the first year of follow-up two further HRIs were diagnosed with IPMNs, bringing this rate to 32%.
Conclusion: The rate of pancreatic changes observed in HRIs at the first round of surveillance with MRI/MRCP does not differ from that of controls. Most abnormalities do not have clinical significance, the most common being parenchymal atrophy and small BD-IPMNs without worrisome features. These results differ from those previously reported regarding EUS, possibly suggesting that EUS might diagnose more frequently subtle pancreatic changes as compared to MRI in HRIs.Background & Aims: Pancreatic cystic lesions (PCLs) are frequent incidental findings. As most PCLs require costly diagnostic evaluation and active surveillance, it is important to clarify their prevalence in asymptomatic individuals. We therefore aimed at performing a systematic review and meta-analysis to determine it.
Methods: a systematic search was conducted and studies meeting inclusion criteria were included. The prevalence of PCLs was pooled across studies. A random effect model was used with assessment of heterogeneity.
Results: 17 studies, with 48,860 patients, were included. Only 3 were prospective; 5 studies were conducted in the US, 7 in Europe, 4 in Asia and 1 in Brazil. The pooled prevalence of PCLs was 8% (95% CI 4-14) with considerable heterogeneity (I2=99.5%). This prevalence was higher in studies of higher quality, examining older subjects, smaller cohorts, and employing MRCP (24.8%
vs 2.7% with CT-scan). The pooled rate of PCLs was four times higher in studies conducted in the US than in Asia (12.6% vs 3.1%). 7 studies reported the prevalence of mucinous lesions, with a
pooled rate of 4.3% (95% CI 2-10; I2=99.2%), but of 0.7% only for worrisome features or high risk stigmata.
Conclusion: The rate of incidentally detected PCLs is of 8%. Mucinous lesions are the most common incidentally detected PCLs, although they rarely present with potential indication for surgery. The observed different rates in the US and other geographic Areas suggest that different protocols might be necessary to help balancing costs and effectiveness of follow-up investigations in asymptomatic subject
Endoscopy-guided ablation of pancreatic lesions: technical possibilities and clinical outlook
No full textRepeated transabdominal ultrasonography is a simple and accurate strategy to diagnose a biliary etiology of acute pancreatitis.
No full textTransabdominal ultrasonography (US) usually reveals diagnosis of biliary acute pancreatitis (AP). Guidelines suggest repeating US in AP patients without cause at first examination. This approach has been poorly investigated, as well as the accuracy of repeated US as compared with that of magnetic resonance cholangiopancreatography. This study aims at evaluating the diagnostic accuracy of repeated US for biliary AP.The accuracy of each test for diagnosis of biliary AP was evaluated according to the final diagnosis. Comparison between tests was obtained by examining the areas under the receiver operating characteristic curves.Among 155 patients, the etiology was biliary in 52\% and alcoholic in 20\%. The accuracy of the first US alone and of the 2 combined examinations for a biliary etiology were 66\% and 83\%, respectively. Comparison of receiver operating characteristic curves showed a better performance of repeated US (difference between areas under the curve, 0.135; 95\% confidence interval, 0.02-0.24; P = 0.021). Magnetic resonance cholangiopancreatography had high specificity (93\%) but low sensitivity (62\%), with 76\% accuracy. The accuracy of the combination of the 2 US examinations and of elevated alanine transferase was 87\%.Repeated US is effective for biliary AP diagnosis. The combination of repeated US examinations and biochemical tests seems an effective approach, whereas magnetic resonance cholangiopancreatography might be restricted to selected cases
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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