Endoscopic Ultrasound-guided Fine Needle Aspiration Of Solid Pancreatic Lesions Research Articles

Comparison of the diagnostic yield of rapid versus non-rapid onsite evaluation in endoscopic ultrasound-guided fine-needle aspiration cytology of solid pancreatic lesions.

The role of rapid on-site evaluation (ROSE) for endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of pancreatic lesions is debatable. In this study, we aimed to compare the diagnostic yield of ROSE vs. non-ROSE in solid pancreatic lesions. This retrospective single-center study included patients undergoing EUS-FNA of solid pancreatic lesions from 2019-2021. Patients with cystic lesions, those undergoing fine-needle core biopsy, those undergoing repeat procedures, and patients with non-diagnostic smears with less than 6-month follow up were excluded. The diagnostic yield, need for repeat procedures and number of passes required with and without ROSE were analyzed in these patients. Of the 111 patients included, 56 underwent ROSE. The majority of lesions were malignant in both groups (79.6% ROSE vs. 75% non-ROSE). The diagnostic yield was 96.4% in the ROSE group and 94.5% in the non-ROSE group. Repeat samples were needed in 1 ROSE and 2 non-ROSE patients. The median number of passes made was significantly fewer in the ROSE group (3.5, interquartile range - 3,4) compared with the non-ROSE group (4, interquartile range - 3,5) P=0.01. However, the frequency of procedure-related complications was similar in both groups. The utilization of ROSE during EUS-FNA of solid pancreatic lesions does not affect the diagnostic yield or the need for repeat samples, but reduces the number of passes needed for acquiring samples.

The impact of biliary stents on the diagnostic yield of endoscopic ultrasound-guided fine needle aspiration for solid pancreatic lesions: A single-center retrospective study and meta-analysis.

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is widely used for the pathological diagnosis of solid pancreatic lesions but in cases with obstructive jaundice, transpapillary sampling can be performed during endoscopic retrograde cholangiopancreatography with transpapillary biliary stent placement. Thus, it is still controversial whether EUS-FNA should be performed prior to endoscopic retrograde cholangiopancreatography with biliary stent placement or only after negative transpapillary sampling. The accuracy, sensitivity, and specificity of EUS-FNA for solid pancreatic lesions with or without indwelling biliary stents were retrospectively studied in patients undergoing EUS-FNA between January 2017 and December 2021. We also conducted a meta-analysis including our data to compare the accuracy and sensitivity of EUS-FNA with or without biliary stents. A total of 509 patients (40 with biliary stents and 469 without biliary stents) were included. The accuracy (77.5% vs. 94.5%, p < 0.001) and sensitivity (71.0% vs. 91.7%, p < 0.001) were lower in EUS-FNA with biliary stents. A meta-analysis confirmed that accuracy (odds ratio [OR] of 0.43, 95% confidence interval [CI] 0.29-0.62, p < 0.001) and sensitivity (OR of 0.46, 95% CI 0.33-0.64, p < 0.001) were lower in EUS-FNA with biliary stents. There were no statistically significant differences between plastic stents and self-expandable metallic stents for accuracy or sensitivity. The presence of biliary stents had a negative impact on the diagnostic performance of EUS-FNA, and EUS-FNA prior to endoscopic retrograde cholangiopancreatography with biliary stent placement should be considered in cases with obstructive jaundice.

Rapid on-site evaluation improves the sensitivity of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) for solid pancreatic lesions irrespective of technique: A single-centre experience.

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is the first-line technique for the sampling of pancreatic lesions. Many factors can influence the diagnostic performance of this procedure, including the use of rapid on-site evaluation (ROSE). The primary aim of this study was to compare the adequacy, diagnostic yield, accuracy, sensitivity and specificity of EUS-FNA for solid pancreatic lesions before and after the introduction of ROSE. This retrospective single-centre study evaluated all consecutive patients who underwent EUS-FNA for suspicious, solid pancreatic masses from April 2012 to March 2015. We compared the findings of EUS-FNA procedures performed during the first and second years following the adoption of ROSE ("ROSE1" and "ROSE2", respectively) to those performed the year before ROSE introduction (the "pre-ROSE" group). Ninety-one consecutive patients with a total of 93 pancreatic lesions were enrolled. For the pre-ROSE, ROSE1 and ROSE2 groups, the adequacy rates were 96.2%, 96.6% and 100%, the diagnostic yield values were 76.9%, 89.7% and 92.1% and accuracy values were 69.2%, 86.2% and 89.5% (p = NS). Sensitivity for malignancy improved from 63.7% in the pre-ROSE group to 91.7% and 91.2% in the post-ROSE groups (p < 0.05). Specificity for malignancy was 100% in all groups. ROSE can improve the diagnostic performance of EUS-FNA for solid pancreatic lesions, although only sensitivity reached statistical significance.

Diagnostic yield and agreement on fine-needle specimens from solid pancreatic lesions: comparing the smear technique to liquid-based cytology

Background and study aims The traditional “smear technique” for processing and assessing endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is sensitive to artifacts. Processing and evaluation of specimens collected in a liquid medium, liquid-based cytology (LBC) may be a solution. We compared the diagnostic value of EUS-FNA smears to LBC in pancreatic solid lesions in the absence of rapid on-site evaluation (ROSE). Patients and methods Consecutive patients who required EUS-FNA of a solid pancreatic lesion were included in seven hospitals in the Netherlands and followed for at least 12 months. Specimens from the first pass were split into two smears and a vial for LBC (using ThinPrep and/or Cell block). Smear and LBC were compared in terms of diagnostic accuracy for malignancy, sample quality, and diagnostic agreement between three cytopathologists. Results Diagnostic accuracy for malignancy was higher for LBC (82 % (58/71)) than for smear (66 % (47/71), P = 0.04), but did not differ when smears were compared to ThinPrep (71 % (30/42), P = 0.56) or Cell block (62 % (39/63), P = 0.61) individually. Artifacts were less often present in ThinPrep (57 % (24/42), P = 0.02) or Cell block samples (40 % (25/63), P < 0.001) than smears (76 % (54/71)). Agreement on malignancy was equally good for smears and LBC (ĸ = 0.71 versus ĸ = 0.70, P = 0.98), but lower for ThinPrep (ĸ = 0.26, P = 0.01) than smears. Conclusion After a single pass, LBC provides higher diagnostic accuracy than the conventional smear technique for EUS-FNA of solid pancreatic lesions in the absence of ROSE. Therefore, LBC, may be an alternative to the conventional smear technique, especially in centers lacking ROSE.

Finding a needle in a haystack: Endoscopic ultrasound-guided fine-needle aspiration for solid pancreatic masses in the setting of chronic pancreatitis.

Background:The mainstay for the definitive diagnosis of pancreatic lesions is endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). However, there is evidence that EUS-FNA has low sensitivity in the setting of chronic pancreatitis (CP). This single-center retrospective study aimed to compare and analyze the diagnostic yield of EUS-FNA for solid pancreatic lesions in the presence and absence of CP, and to further investigate strategies for overcoming the low diagnostic yield in the setting of CP.Methods:This study identified patients who underwent EUS-FNA at Sanford USD Medical Center (SD, USA) for a solid pancreatic lesion between July 15, 2011, and November 30, 2017. Data on demographics, clinical features, cross-sectional imaging findings, EUS findings, cytology/pathology, and clinical follow up were collected.Results:The final diagnosis was adenocarcinoma in 156 patients (67%), neuroendocrine tumor in 27 (12%), lymphoma in 6 (3%), metastatic malignancy in 8 (4%), and benign etiologies in 35 (15%). CP was identified in 44/234 (19%) patients. The overall diagnostic sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for EUS-FNA were 92.9%, 97.1%, 99.5%, 70.8%, and 93.5%, respectively. The sensitivity (80% vs. 95%, P=0.020) and accuracy (86% vs. 95%, P=0.043) were significantly lower in patients with CP compared to those without CP.Conclusion:CP can significantly affect the EUS-FNA diagnostic yield of solid pancreatic neoplasms. A high index of clinical suspicion is required in these cases to make a definitive diagnosis.

Instant messenger smartphone application for endosonographer/cytopathologist real-time interaction at a distance in EUS-FNA for solid pancreatic lesions.

Background and study aims Telecytopathology (TCP) may allow proper and timely evaluation of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) specimens. The aim of this study was to evaluate the feasibility of TC through a multiplatform instant messenger smartphone application to evaluate specimens of EUS-FNA of pancreatic solid lesions. Patients and methods Twenty-three patients (14 male/9 female; median age: 56 yr.; age range: 33 – 86) with a solid pancreatic lesion were included. Exclusion criteria were as follows: age < 18 yr and predominantly cystic lesions. During each EUS-FNA, after each pass, the aspirated material was spread over a glass slide and was stained by the endoscopist. The glass slide was then reviewed on a microscope with a smartphone fitted in, and the most representative fields were captured and sent to the cytopathologist using WhatsApp Messenger. Results In initial evaluation using TCP rapid on-site evaluation (ROSE), adequate cellularity of the glass slide was detected in 16 of 23 patients (69.6 %). An initial diagnosis of malignancy (positive or suspicious) was possible in 14 of 23 patients (60.8 %). Conclusion The current study demonstrated the feasibility of a low-cost, Internet-based, telecytopathology system using WhatsApp Messenger to provide ROSE of EUS-FNA slides in patients with solid pancreatic lesions.

Diagnostic yield of EUS-FNA of small (≤15 mm) solid pancreatic lesions using a 25-gauge needle

BackgroundEarly detection of small solid pancreatic lesions is increasingly common. To date, few and contradictory data have been published about the relationship between lesion size and endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) diagnostic yield. The aim of this study was to assess the relation between the size of solid pancreatic lesions and the diagnostic yield of EUS-FNA using a 25-gauge needle in a center without available rapid on-site evaluation. MethodsIn the retrospective cohort study, we selected patients who underwent EUS-FNA for solid pancreatic lesions with a 25-gauge needle from October 2014 to October 2015. Patients were divided into three groups (≤15 mm, 16–25 mm and >25 mm), and the outcomes were compared. ResultsWe analyzed 163 patients. Overall adequacy, sensitivity, specificity and accuracy were 85.2%, 81.8%, 93.7%, and 80.4%, respectively. When stratified by size, the sensitivity and accuracy correlated with size (P = 0.016 and P = 0.042, respectively). Multivariate analysis showed that lesion size was the only independent factor (P = 0.019, OR = 4.76) affecting accuracy. The role of size as an independent factor affecting accuracy was confirmed in a separate multivariate analysis, where size was included in the model as a covariate (P = 0.018, OR = 1.08). ConclusionOur study demonstrates that, in the absence of rapid on-site evaluation, mass size affects the accuracy of EUS-FNA of solid pancreatic lesions.

Diagnostic efficacy of liquid-based cytology for solid pancreatic lesion samples obtained with endoscopic ultrasound-guided fine-needle aspiration: Propensity score-matched analysis.

There is a paucity of data on the diagnostic efficacy of liquid-based cytology (LBC) for pancreatic samples obtained by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). Using propensity score matching, we retrospectively analyzed the additional diagnostic value of LBC compared to a conventional Papanicolaou smear (CPS) for samples of solid pancreatic lesions obtained by EUS-FNA. This cohort study included 126 matched patients who underwent initial EUS-FNA for solid pancreatic lesions between January 2009 and August 2014. CPS was used for cytology of EUS-FNA samples obtained until May 2012 (63 patients). Subsequently, LBC was used for cytological analysis (63 patients). Diagnostic yields of CPS and LBC for malignancy were compared. Risk factors for cytological misdiagnosis with LBC were investigated. Overall rate of malignancy was 86% after matching. LBC had higher diagnostic sensitivity and accuracy than CPS (96.6% vs 84.0%, P = 0.03; and 96.8% vs 87.3%, P = 0.05). LBC was significantly more sensitive for diagnosing pancreatic head lesions (96.4% vs 78.1%, P = 0.04). The sensitivity for pancreatic ductal adenocarcinoma (PDAC) with LBC was higher (98.1% vs 83.0%, P = 0.009). Multivariate analysis revealed that malignant tumors other than PDAC (P = 0.004) and lesion size ≤20 mm (P = 0.046) were risk factors for LBC misdiagnosis in all participants. For solid pancreatic lesions, LBC of EUS-FNA samples contributes to the diagnosis of malignancy. Malignant tumors other than PDAC and small tumors are difficult to diagnose using EUS-FNA and LBC.

Effect of the time of day and queue position in the endoscopic schedule on the performance characteristics of endoscopic ultrasound-guided fine-needle aspiration for diagnosing pancreatic malignancies.

Background and Objectives:Recent reports have indicated that the time of day may impact the detection rate of abnormal cytology on gynecologic cytology samples. The aim of this study was to determine if procedure time or queue position affected the performance characteristics of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for diagnosing solid pancreatic malignancies.Patients and Methods:We conducted a retrospective study evaluating patients with solid pancreatic lesions in whom EUS-FNA was performed. Three timing variables were evaluated as surrogate markers for endoscopist fatigue: Procedure start times, morning versus afternoon procedures, and endoscopy queue position. Statistical analyses were performed to determine whether the timing variables predicted performance characteristics of EUS-FNA.Results:We identified 609 patients (mean age: 65.8 years, 52.1% males) with solid pancreatic lesions who underwent EUS-FNA. The sensitivity of EUS-FNA was 100% for procedures that started at 7 AM while cases that started at 4 PM had a sensitivity of 81%. Using start time on a continuous scale, each elapsed hour was associated with a 1.9% decrease in EUS-FNA sensitivity (P = 0.003). Similarly, a 10% reduction in EUS-FNA sensitivity was detected between morning and afternoon procedures (92% vs. 82% respectively, P = 0.0006). A linear regression comparing the procedure start time and diagnostic accuracy revealed a decrease of approximately 1.7% in procedure accuracy for every hour later a procedure was started. A 16% reduction in EUS-FNA accuracy was detected between morning and afternoon procedures (100% vs. 84% respectively, P = 0.0009). When the queue position was assessed, a 2.4% reduction in accuracy was noted for each increase in the queue position (P = 0.013).Conclusion:Sensitivity and diagnostic accuracy of EUS-FNA for solid pancreatic lesions decline with progressively later EUS starting times and increasing numbers of procedures before a given EUS, potentially from endoscopist fatigue and cytotechnologist fatigue.

Comparison of Capillary Versus Aspiration Technique in Endoscopic Ultrasound-Guided Fine-Needle Aspiration for Solid Pancreatic Lesions: Presidential Poster

Introduction: Application of suction during endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of solid pancreatic lesions is still controversial. The fine-needle stylet “capillary technique,” which uses only capillary aspiration achieved by slow withdrawal of the stylet has recently been proposed. The aim of this study was to compare the performance characteristics of EUS-FNA for evaluating solid pancreatic lesions using the standard “suction” and the “capillary” techniques. Methods: A retrospective review of consecutive patients with solid pancreatic lesions who underwent EUS-FNA using a 22 G needle from 2006 to 2013 was performed. Patients were divided into 2 groups: a) between 2002 and 2012, EUS-FNA was performed using the “suction” technique, and b) beginning 2013, FNA was performed using the “capillary” technique. Performance characteristics of EUS-FNA including the sensitivity, specificity, and the number of needle passes to obtain diagnosis were compared between the 2 groups. Results: A total of 973 patients (51% male; mean age 65.7 years) were evaluated. There was no difference between the groups in age, sex, and size of pancreatic mass. Cytological final diagnosis was adenocarcinoma in 81.8% cases, neuroendocrine tumor 4.7%, intraductal papillary mucosal neoplasms with high-grade dysplasia in 5.4%, metastatic disease in 4.4%, and negative for malignant cells in 3.7%. The sensitivity and specificity of EUS-FNA were higher in the “capillary” group when compared to the “suction” group (96.9, 100%, and 90.3, 81.7%, respectively; p=0.002). The numbers of passes required to obtain a diagnosis in the capillary group was two-thirds that of the suction group (incidence rate ratio 0.65; p<0.001). The mean number of needle passes required to make a diagnosis in the capillary group was significantly less when compared to the suction group (1.9 vs. 2.9, respectively; p=0.05). Conclusion: The “capillary” technique is superior to the traditional “suction” technique in EUS-FNA of solid pancreatic lesions in overall sensitivity, specificity, and on a per-pass basis. It can acquire a definitive tissue diagnosis on cytological smear in fewer passes and can potentially decrease risk to the patient.

Impact of rapid on-site evaluation on the adequacy of endoscopic-ultrasound guided fine-needle aspiration of solid pancreatic lesions: a systematic review and meta-analysis.

Rapid on-site evaluation (ROSE) has the potential to improve adequacy rates for endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) of solid pancreatic lesions, but its impact is context-dependent. No studies exist that summarize the relationship between ROSE, number of needle passes, and resulting adequacy rates. To analyze data from previous studies to establish if ROSE is associated with improved adequacy rates; to evaluate the relationship between ROSE, number of needle passes, and the resulting adequacy rates of EUS-FNA for solid pancreatic lesions. Systematic review and meta-analysis of studies reporting the adequacy rates for EUS-FNA of solid pancreatic lesions. The search produced 3822 original studies, of which 70 studies met our inclusion criteria. The overall average adequacy rate was 96.2% (95% confidence interval: 95.5, 96.9). ROSE was associated with a statistically significant improvement of up to 3.5% in adequacy rates. There was heterogeneity in adequacy rates across all subgroups. No association between the assessor type and adequacy rates was found. Studies with ROSE have high per-case adequacy and a relatively high number of needle passes in contrast to non-ROSE studies. ROSE is an effect modifier of the relationship between number of needle passes and adequacy. ROSE is associated with up to 3.5% improvement in adequacy rates for EUS-FNA of solid pancreatic lesions. ROSE assessor type has no impact on adequacy rates. ROSE is an effect modifier on the relationship between needle passes and per-case adequacy for EUS-FNA of solid pancreatic lesions.

Rapid on‐site evaluation for endoscopic ultrasound‐guided fine‐needle biopsy of the pancreas decreases the incidence of repeat biopsy procedures

Rapid on-site evaluation (ROSE) for endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) biopsy of the pancreas provides immediate feedback regarding cellular adequacy to aid in obtaining a definitive diagnosis and has the potential to avoid repeat procedures. The objective of the current study was to measure the impact of ROSE service on the incidence of repeat EUS FNA biopsy procedures. Over a consecutive 3-year period, the pathology database at Washington University Medical Center was searched for patients with both an initial and subsequent EUS FNA biopsy demonstrating a solid lesion of the pancreas. These were divided temporally between the time before and after the introduction of ROSE service. Reports were reviewed and results were recorded. A total of 379 patients underwent ROSE service and 377 patients did not. The percentage of repeat non-ROSE EUS FNA cases was 5.8% and the percentage of repeat ROSE EUS FNA cases was 2.9%. The use of the ROSE service was found to decrease the number of repeat procedures by approximately 50% (P = .024). For those patients who underwent a repeat EUS-FNA procedure, the ROSE service provided a higher rate of definitive diagnosis among patients undergoing repeat procedures (67%) versus the non-ROSE cohort (27%). The use of ROSE for EUS-FNA biopsy of the pancreas was found to result in fewer patients undergoing repeat procedures. Patients who required a repeat procedure with the use of ROSE had a higher percentage of definitive diagnostic categorization on the repeat biopsy. Initial use of ROSE for EUS-FNA of solid pancreatic lesions was found to decrease the number of patients who required a repeat procedure.

Is It Time to Take a Pass on the Increased Number of Passes in EUS-FNA?

Despite the extensive use of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), there still exists a wide variation in the number of samples required to ensure acquisition of diagnostic material from pancreatic lesions. Although multiple passes can be performed during EUSFNA, prolonging the procedure likely increases risk, decreases procedural efficiency, and increases the probability of samples being tainted with blood. It has been 21 years since EUS-FNA was used to obtain pancreatic tissue for cytologic analysis [1, 2], 16 years since the publication of the first reports evaluating the clinical impact and staging of pancreatic lesions sampled by EUSFNA [3], and 14 years since the publication of the initial reports of the evaluation of the number of passes needed to obtain a diagnostic yield and the significance of on-site cytopathology during the procedure [4–7]. During this time, the focus has been on determining the necessity of on-site cytopathologic evaluation, the optimal number of needle passes, and the most effective needle type used for tissue acquisition. Despite numerous studies addressing these issues, many endoscopists are still perplexed about the nature of the best practices needed to ensure optimal results, in particular with regard to the need for on-site cytopathology for skilled and experienced endosonographers practicing at a high-volume center. To date, multiple meta-analyses have confirmed the diagnostic accuracy, cost-effectiveness, accuracy, and safety of EUS-FNA for solid pancreatic lesions [8–12]. Moreover, structured literature reviews have concluded that rapid on-site evaluation (ROSE) improves diagnostic accuracy [8, 9]. Notwithstanding these considerable successes, ongoing refinements to EUS-FNA continue to be explored. Regardless of the likelihood that increasing numbers of passes raises the risk of needle failure, tissue injury, postprocedural complications, and medical expenses, the endosonographer is caught between the need to provide adequate tissue needed to optimize diagnostic yield weighed against the cost and risk of making additional passes. Failed EUS-FNA often engenders additional risk and expense due to the need to repeat EUS or to obtain tissue with radiologic or surgical guidance. Moreover, as treatment options for pancreatic cancer advance, rendering an onsite diagnosis alone may not be adequate, since additional tissue may be required to perform ancillary studies and molecular mapping. Nevertheless, ROSE may not be financially viable due to excess time commitment, limited resources, relatively low reimbursements, and acceptable adequacy rates achieved by more experienced endosonographers. In order to have a sustainable EUS practice with optimal clinical outcomes, it may be beneficial to provide some degree of ROSE training for endosonographers incorporating the ‘‘fanning’’ FNA technique combined with an algorithmic approach to needle selection [13–15]. In this issue of Digestive Diseases and Sciences, Schmidt et al. [16] examined current practices of lesion sampling, weighing diagnostic accuracy against the probability of adverse events in the presence and absence of ROSE. The authors provide empirical data regarding the diagnostic yield and performance characteristics of EUS-FNA of solid pancreatic lesions using mathematical modeling to determine the likelihood of adverse events with a fixed number of passes (no-ROSE) versus a variable number of passes (ROSE) while controlling for other variables. Schmidt and colleagues used a discrete-event simulation model to conclude that ROSE reduces the number of passes, thereby reducing the S. Hebert-Magee R. H. Hawes S. Varadarajulu (&) Center for Interventional Endoscopy, Florida Hospital, 601 East Rollins Street, Orlando, FL 32803, USA e-mail: svaradarajulu@yahoo.com

Optimizing specimen collection and laboratory procedures reduces the non‐diagnostic rate for endoscopic ultrasound‐guided fine‐needle aspiration of solid lesions of the pancreas

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a routine technique to assess solid pancreatic lesions. The aim of this study was to analyse the effect of optimizing laboratory procedures for specimen preparation on the rate and accuracy of the procedure. All EUS-FNAs of solid pancreatic lesions performed during the year 2000 (Period 1) and from May 2003 to May 2004 (Period 2) were analysed. During Period 1, one experienced gastroenterologist performed all EUS-FNAs, making direct smears and retrieving small fragments if present on the smear for histology. In Period 2, two endoscopists performed the EUS-FNAs and all the material was emptied into a vial containing a fixative. Slide preparation was carried out in the pathology laboratory: one slide was processed using cytocentrifugation and cell blocks were made from left-over material. Neither period utilized rapid on-site evaluation. During the two periods, 67 and 102 FNAs were analysed and showed significantly different (P < 0.001) non-diagnostic rates of 22.8% and 4.2%, respectively. The increased diagnostic yield can be explained by the modified laboratory procedures and to a lesser extent by the increased experience of the gastroenterologists. Sensitivity, specificity, PPV, NPV and accuracy in the second time period were, respectively, 90.6%, 100%, 100%, 81.8% and 93.4%, not significantly different from the first time period. This study shows that accurate EUS-FNA results may be obtained with a low non-diagnostic rate comparable to those reported for rapid on-site evaluation by optimizing laboratory specimen processing in a setting of solid pancreatic lesions.

Relationship of Pancreatic Mass Size and Diagnostic Yield of Endoscopic Ultrasound-Guided Fine Needle Aspiration

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is central to discerning the diagnosis of solid pancreatic tumors through tissue acquisition. Test performance is affected by a number of factors including location of mass within the pancreas, presence of onsite cytology technologist, and number of passes with the needle. The influence of tumor size has not been well studied. The objective of the current study was to determine whether the size of mass affects the diagnostic accuracy for solid pancreatic lesions aspirated under EUS guidance. Data were collected retrospectively on all patients with solid pancreatic masses undergoing EUS-FNA from June 2003 to August 2010. The cytology samples were reported as positive, suspicious for malignancy, atypical, negative, or nondiagnostic. The gold standard for a cytological diagnosis was histological confirmation or clinical follow-up of more than 6months with repeat imaging. Patients were divided into five groups based upon lesion size as follows: (a) less than 1cm, (b) 1-2cm, (c) 2-3cm, (d) 3-4cm, and (e) greater than 4cm. Performance characteristics of EUS-FNA including sensitivity, specificity, and accuracy were compared for each group. Accuracy was defined as the ratio of the sum of true-positive and true-negative values divided by the number of lesions. We identified 583 patients with solid pancreatic lesions in which EUS-FNA was performed and adequate cellularity was obtained (47% men, mean age 65±1.4 (SE) years). Overall, 486 (83%) of lesions were pancreatic adenocarcinoma, 18 (3%) were neuroendocrine tumors, 12 (2%) were lymphomas, and 67 (12%) were benign lesions. The median size of the mass was 3cm (range, 0.5-7cm). A mean of 4.9 passes (range, 1-9 passes) was needed to obtain adequate samples from lesions. The overall yield of obtaining adequate samples for diagnosis was 85%. When stratified by size, the EUS-FNA sensitivity for lesions with size <1, 1-2, 2-3, 3-4, and >4cm was 40, 75.9, 86.9, 93.2, and 91.6%, respectively; EUS-FNA sensitivity strongly correlate with tumor size (p<0.001). Similarly, the accuracy of EUS-FNA increased as lesion size increased, ranging from 47% for tumors less than 1cm to 88% for tumors greater than 4cm (p<0.05). Location of tumor and number of needle passes did not significantly influence EUS-FNA performance characteristics. The sensitivity and diagnostic accuracy of EUS-FNA for solid pancreatic lesions is strongly correlated with tumor size. Sensitivity and accuracy decrease significantly for tumors that are smaller than 1cm.

Effect of dedicated and supervised training on achieving competence in EUS-FNA of solid pancreatic lesions

Background and Aim. The diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has been suggested as a benchmark of quality performance in EUS. However, there is paucity of data on the training requirement for competency in EUS-FNA of the pancreas. KO commenced the service without prior formal training in EUS-FNA. A formally trained colleague (MN) who underwent a fellowship in the same unit was appointed to a substantive post in 2007. The aims of the study were to assess if a dedicated training program in pancreaticobiliary (PB) EUS-FNA of solid lesions: (1) produced better results at the outset of independent practice than produced at the initiation of service without formal training and (2) produced results comparable with those of an experienced endosonographer. Material and methods. This is a retrospective review comparing the first 80 consecutive cases at the onset of practice of operator KO1 (2003/2004) and MN (2007/2008) as well as consecutive cases of operator KO2 (2007/2008) in the same time frame as the initial cases of operator MN. Results. There was a significant difference in EUS-FNA sensitivity for pancreatic malignancy between operator KO1 (56%) and operator MN (77%) p < 0.05. There was no significant difference in test performance between operator KO2 (82%) and MN (77%) (p > 0.05). Conclusion. Our data show that formal training in PB EUS produces test performance at the outset of independent practice that is comparable with an experienced endosonographer, in line with the published standards for EUS-FNA of the pancreas and significantly better than that achieved without training.

PTU-081 Endoscopic ultrasound-guided fine needle aspiration of solid pancreatic lesions: an observational study: Abstract PTU-081

<h3>Introduction</h3> Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) of pancreatic lesions is a valuable tool in the investigation of suspected pancreatic cancer. Recent international studies on the diagnostic utility of this technique have reported sensitivity and accuracy levels of &gt;90%. There is a paucity of UK centre data on diagnostic performance. In this retrospective observational study we aim to report the largest UK cohort and provide comparison with international standards. <h3>Methods</h3> Hammersmith Hospital is a regional pancreatobiliary referral centre. A single experienced endosonographer provides all diagnostic and therapeutic EUS services. A retrospective analysis of patients who underwent EUS-FNA for solid pancreatic lesions between Jan 2006 and Oct 2009 was performed. Cytopathology reports for cases were scrutinised. Cytological diagnosis was compared with the reference standard of surgical or biopsy histology, clinical and radiological evidence of disease progression, or in the case of benign cytology a minimum of 6 months clinical follow-up. <h3>Results</h3> A total of 113 EUS-FNAs for a solid pancreatic lesion were identified during the study period (average age 66 years, M/F ratio 1.1:1). The final outcomes were: pancreatic carcinoma (87/113, 77%), benign disease or pancreatitis (18/113, 16%) neuroendocrine tumour (5/113, 4%), metastasis (2/113, 1.7%), lymphoma (1/113, 0.8%). 15/113 cytology specimens were graded as “C4” or “highly suspicious of adenocarcinoma”, and in all the final diagnosis was pancreatic adenocarcinoma (PPV 100%). Performance characteristics were calculated both considering the C4/suspicious specimens as false negatives for malignancy and true positives (Abstract 081). Comparing the performance of EUS-guided FNA in years 2006–2007 to years 2008–2009 there was an improvement in sensitivity (78% to 92%) and accuracy (82% to 93%), respectively. <h3>Conclusion</h3> In solid pancreatic lesions FNA specimens classified cytologically as C4 have a 100% PPV for adenocarcinoma and should be considered diagnostic for this. The performance of EUS-FNA of solid pancreatic lesions in our institution, a UK regional referral centre, is comparable to international standards. A recent improvement in sensitivities and accuracy to in excess of 90% was noted. Further endosonographer experience, better case selection and routine use of “in-room” cytopathologist support may account for this and should be considered as strategies to improve accuracy further.