Endoscopic ultrasound-guided fine-needle aspiration: sampling, pitfalls, and quality management

A deep learning model to triage and predict adenocarcinoma on pancreas cytology whole slide imaging

Pancreatic fine-needle aspirations are the gold-standard diagnostic procedure for the evaluation of pancreatic ductal adenocarcinoma. A suspicion for malignancy can escalate towards chemotherapy followed by a major surgery and therefore is a high-stakes task for the pathologist. In this paper, we propose a deep learning framework, MIPCL, that can serve as a helpful screening tool, predicting the presence or absence of cancer. We also reproduce two deep learning models that have found success in surgical pathology for our cytopathology study. Our MIPCL significantly improves over both models across all evaluated metrics (F1-Score: 87.97% vs 88.70% vs 91.07%; AUROC: 0.9159 vs. 0.9051 vs 0.9435). Additionally, our model is able to recover the most contributing regions on the slide for the final prediction. We also present a dataset curation strategy that increases the number of training examples from an existing dataset, thereby reducing the resource burden tied to collecting and scanning additional cases.

Endoscopic ultrasound-guided tissue acquisition with or without rapid on-site evaluation for solid pancreatic lesions: five years of experience from a single center

BACKGROUND

Endoscopic ultrasound (EUS)-guided tissue acquisition (TA) by EUS-guided fine needle aspiration (FNA) or fine needle biopsy (FNB) is a standard diagnostic procedure for solid pancreatic lesions. Whether rapid on-site evaluation (ROSE) should be used to support EUS-TA remains controversial. Here we assessed the diagnostic performance of EUS-TA with or without self-ROSE for solid pancreatic masses.

METHODS

Three hundred and seventy EUS-TA cases with self-ROSE and 244 cases without ROSE were retrospectively enrolled between August 2018 and June 2022. All procedures including ROSE were performed by the attending endoscopist. Clinical data, EUS characteristics, and diagnostic performance for distinguishing benign from malignant solid pancreatic masses including accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were compared between groups.

RESULTS

Self-ROSE improved the diagnostic accuracy of solid pancreatic lesions by 16.7% in the EUS-TA group (p < 0.001) and by 18.9% in the EUS-FNA alone group (p < 0.001). Self-ROSE also improved the diagnostic sensitivity by 18.6% in the EUS-TA group (p < 0.001) and by 21.2% in the EUS-FNA alone group (p < 0.001). Improvements in the diagnostic accuracy by self-ROSE in the EUS-FNB group were not significant. 2.2 ± 0.7, 2.4 ± 0.9, 2.3 ± 0.7, 2.5 ± 0.9, 2.1 ± 0.6, and 2.1 ± 0.7 needle passes were required in the EUS-TA, EUS-FNA, and EUS-FNB with or without self-ROSE groups, respectively.

CONCLUSIONS

Self-ROSE significantly improved the accuracy and sensitivity of EUS-FNA alone and EUS-TA diagnosis of solid pancreatic lesions and helped to reduce needle passes during the procedure. Whether self-ROSE benefits EUS-FNB and whether EUS-FNB alone is comparable to EUS-FNA with self-ROSE require further clarification.

Endoscopic ultrasound (EUS)-guided fine needle biopsy alone vs. EUS-guided fine needle aspiration with rapid onsite evaluation in pancreatic lesions: a multicenter randomized trial

BACKGROUND

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is the standard in the diagnosis of solid pancreatic lesions, in particular when combined with rapid onsite evaluation of cytopathology (ROSE). More recently, a fork-tip needle for core biopsy (FNB) has been shown to be associated with excellent diagnostic yield. EUS-FNB alone has however not been compared with EUS-FNA + ROSE in a large clinical trial. Our aim was to compare EUS-FNB alone to EUS-FNA + ROSE in solid pancreatic lesions.

METHODS

A multicenter, non-inferiority, randomized controlled trial involving seven centers was performed. Solid pancreatic lesions referred for EUS were considered for inclusion. The primary end point was diagnostic accuracy. Secondary end points included sensitivity/specificity, mean number of needle passes, and cost.

RESULTS

235 patients were randomized: 115 EUS-FNB alone and 120 EUS-FNA + ROSE. Overall, 217 patients had malignant histology. The diagnostic accuracy for malignancy of EUS-FNB alone was non-inferior to EUS-FNA + ROSE at 92.2 % (95 %CI 86.6 %-96.9 %) and 93.3 % (95 %CI 88.8 %-97.9 %), respectively (P = 0.72). Diagnostic sensitivity for malignancy was 92.5 % (95 %CI 85.7 %-96.7 %) for EUS-FNB alone vs. 96.5 % (93.0 %-98.6 %) for EUS-FNA + ROSE (P = 0.46), while specificity was 100 % in both. Adequate histological yield was obtained in 87.5 % of the EUS-FNB samples. The mean (SD) number of needle passes and procedure time favored EUS-FNB alone (2.3 [0.6] passes vs. 3.0 [1.1] passes [P < 0.001]; and 19.3 [8.0] vs. 22.7 [10.8] minutes [P = 0.008]). EUS-FNB alone cost on average 45 US dollars more than EUS-FNA + ROSE.

CONCLUSION

EUS-FNB alone is non-inferior to EUS-FNA + ROSE and is associated with fewer needle passes, shorter procedure time, and excellent histological yield at comparable cost.

Impact of biliary stents on the diagnostic accuracy of EUS-guided fine-needle biopsy of solid pancreatic head lesions: A multicenter study

BACKGROUND AND OBJECTIVES

There is no clear evidence of a negative impact of biliary stents on the diagnostic yield of EUS-guided fine-needle biopsy (EUS-FNB) for diagnosing pancreatic head lesions. We aimed to evaluate the association between the presence of biliary stents and the diagnostic accuracy of EUS-FNB.

MATERIALS AND METHODS

A multicenter retrospective study including all jaundiced patients secondary to pancreatic head masses was performed. Patients were divided into two groups according to the presence of a biliary stent placed before EUS-FNB. Pathological results were classified according to the Papanicolaou classification and compared against the final diagnosis. Diagnostic measures in the two groups were compared. Multivariate logistic regression analyses including potential factors affecting EUS-FNB accuracy were performed.

RESULTS

Overall, 842 patients were included, 495 (58.8%) without and 347 (41.2%) with biliary stent. A plastic or a metal stent was placed in 217 (62.5%) and 130 (37.5%) cases, respectively. Diagnostic sensitivity and accuracy were significantly higher in patients without biliary stent than in those with stent (91.9% and 92.1% vs. 85.9% and 86.4%, P = 0.010 At multivariate analyses, lesion size (odds ratio [OR]: 1.05, 95% confidence interval [CI]: 1.02-1.09, P = 0.01) and presence of biliary stent (OR: 0.51, 95% CI: 0.32-0.89, P = 0.01) were independently associated with diagnostic accuracy. In the subgroup of patients with biliary stent, the type of stent (plastic vs. metal) did not impact EUS-FNB yield, whereas the use of larger bore needles enhanced diagnostic accuracy (OR: 2.29, 95% CI: 1.28-4.12, P = 0.005).

CONCLUSIONS

In this large retrospective study, an indwelling biliary stent negatively impacted the diagnostic accuracy of EUS-FNB. Preferably, EUS-FNB should precede endoscopic retrograde cholangiopancreatography, especially in the case of small tumors.

Endoscopic Ultrasound-Guided Fine-Needle Aspiration (EUS-FNA) with Image Enhancement

Although endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is useful in the differential diagnosis of solid pancreatic lesions, lymph nodes, and liver lesions, inadequate sampling may result in an incorrect pathological diagnosis. The accuracy of EUS for the evaluation of pancreatobiliary lesions may be increased by image enhancement technologies, including contrast-enhanced harmonic (CH)-EUS and EUS-elastography. These methods can provide information that complement EUS-FNA for the diagnosis and staging of pancreatobiliary cancer, and can help to identify the EUS-FNA target, reducing the requirement for repeat FNA.

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.

Endoscopic ultrasound-guided sampling of solid pancreatic masses: the fine needle aspiration or fine needle biopsy dilemma. Is the best needle yet to come?

Fine needle aspiration (FNA) is currently the standard of care for sampling pancreatic solid masses by using endoscopic ultrasound (EUS). The accuracy of the technique is reported to be high, especially if coupled with the rapid on site evaluation (ROSE), and it has a high safety profile. However, FNA presents some limitations, such as the small amount of tissue that can be collected and the inability of obtaining a core tissue with intact histological architecture, which is relevant to perform immunohistochemical analysis, molecular profiling and, therefore, targeted therapies. Moreover, the presence of the ROSE by an expert cytopathologist is very important to maximize the diagnostic yield of FNA technique; however, it is not widely available, especially in small centers. Hence, the introduction of EUS fine needle biopsy (FNB) with a new generation of needles, which show a high safety profile too and a satisfying diagnostic accuracy even in the absence of ROSE, could be the key to overcome the limitations of FNA. However, FNB has not yet shown diagnostic superiority over FNA. Considering all the technical aspects of FNA and FNB, the different types of needle currently available, comparisons in term of diagnostic yield, and the different techniques of sampling, a tailored approach should be used in order to determine the needle that is most appropriate for the different specific scenarios.

Diagnostic Endoscopic Ultrasound: Technique, Current Status and Future Directions

Endoscopic ultrasound (EUS) is now well established as an important tool in clinical practice. From purely diagnostic imaging, it has progressed to include tissue acquisition, which provided the basis for therapeutic procedures. Even as interventional EUS developed, there has been ongoing progress in EUS diagnostic capabilities due to improved imaging systems, better needles for tissue acquisition and development of enhanced imaging functions such as contrast harmonic EUS (CHEUS) and EUS elastography. EUS is well established for differentiation of subepithelial lesions, for T-staging of luminal gastrointestinal and pancreaticobiliary malignancies, for differentiation of benign pancreaticobiliary disorders and for diagnostic tissue acquisition, which can be achieved by EUS-guided fine needle aspiration or by EUS-guided fine needle biopsy using dedicated biopsy needles. This review briefly describes the technique of performing EUS and then discusses its clinical utility in terms of gastrointestinal cancer staging, the evaluation of pancreaticobiliary disorders and tissue acquisition. Enhanced imaging techniques such as CHEUS and EUS elastography are briefly reviewed.

Endoscopic Ultrasound-Guided Tissue Acquisition: Techniques and Challenges

Endoscopic ultrasound-guided fine needle aspiration (EUS FNA) has made pathological diagnosis of pancreatic neoplasms, diseases involving lymph nodes at various mediastinal and abdominal sites, gastrointestinal submucosal lesions, perirectal lesions, adrenal lesions, and mediastinal masses easy. EUS-guided FNA is a multistep procedure that involves assessment of proper clinical indication, correct selection of FNA needles, and adoption of evidence-based techniques for tissue sampling. EUS FNA is done by needles that are available in different sizes, mainly 25, 22, and 19-gauge needle. The need of onsite cytopathologist, dependence on histology/core biopsy occasionally to get a diagnosis, and inability to reliably assess for molecular markers are important limitations of EUS FNA. EUS-guided fine needle biopsy (FNB) that samples the core of tissue is an exciting new development in the field of diagnostic EUS. FNB needles are expensive than FNA needles, and although the initial results are encouraging, more studies with robust evidence proving their superiority beyond any doubt are needed before they can be widely used.

Endoscopic ultrasonography-guided tissue acquisition: How to achieve excellence

Endoscopic ultrasound (EUS)-guided tissue acquisition is a basic forte of an endosonographer. The multiple skills required to accomplish successful results include not only the puncture itself, but also proper lesion identification, correct puncture sequence, collaboration with the pathologist onsite or remotely, proper handling of the specimens, choosing one or more of cytology, cell-block, and/or tissue core preparation and, last, deciding the immunohistochemistry (IHC) panels and ancillary tests which may be needed for the current case. Error in any of these decisions may lead to incomplete or inconclusive information from the procedure, even if the aspirate is 'adequate.' In the present review, we will describe the technical aspects of EUS-guided tissue acquisition, current needles available and how to choose between them, and how to appropriately handle the specimen. We will also discuss the optimal approach to common targets including lymph nodes, pancreatic masses, pancreatic cysts, and subepithelial lesions.

Endoscopic ultrasound-guided fine-needle aspiration can target right liver mass

Background and Objectives:

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has been established as a safe and accurate method for diagnosing and staging intra-abdominal mass. However, few studies investigated its feasibility, efficacy, and safety for targeting liver mass. We evaluated the efficacy and safety of EUS-FNA in patients with liver masses including the right lobe.

Patients and Methods:

The technical feasibility, safety, and diagnostic yield were determined in 47 patients (30 in the left lobe and 17 in the right lobe) presenting with liver masses between September 2010 and February 2016.

Results:

Thirty-eight patients (80.9%) had malignancies whereas nine patients (19.1%) had benign liver masses. Technical success rate was 97.9% (46/47). EUS-FNA was diagnostic in 38 of 42 patients (90.5%). When the outcomes of EUS-FNA between right liver mass and left mass were accessed, the technical success rates were similar in both lobes (100% vs. 94.1%, P = 0.2). The median tumor size on EUS (25.5 mm, interquartile range [IQR] 13.8–30.3 vs. 28 mm, IQR 18.5–43.5, P = 0.24) and number of needle passes (3, IQR 3–4 vs. 3, IQR 3–3, P = 0.24) were not significantly different. Adequate specimen obtained was statistically higher in the left lobe (28/30, 93.3% vs. 14/17, 82.4%, P = 0.04). However, diagnostic accuracy for liver masses was not different (25/28, 89.3% vs. 13/14, 92.9%, P = 0.86). No complications developed after procedure.

Conclusions:

EUS-FNA can be a safe and efficient method for the diagnosis of liver mass and it is technically feasible even for those in the right lobe.

KRAS mutation analysis by next-generation sequencing in endoscopic ultrasound-guided sampling for solid liver masses

BACKGROUND AND AIM

KRAS mutation analysis may provide ancillary diagnostic yield in an endoscopic ultrasound (EUS)-guided histopathological evaluation. We evaluated the clinical impact of KRAS mutation analysis with cytological and histological evaluations in EUS-guided tissue sampling, using a core biopsy needle for solid liver masses.

METHODS

EUS-guided fine needle biopsy (EUS-FNB) using a core biopsy needle was performed in patients with primary or metastatic liver masses that were suspected malignancies. KRAS mutations were analyzed in all specimens obtained. The peptide nucleic acid (PNA)-mediated polymerase chain reaction (PCR) clamping method was compared with a next-generation sequencing (NGS) method for detecting KRAS mutations.

RESULTS

EUS-FNB with a core biopsy needle was performed in 28 patients with solid liver masses located in the liver's left lobe. The diagnostic accuracies for malignancy of on-site cytology, cytology using Papanicolaou staining, and histology including immunohistochemical stains were 82.1%, 85.7%, and 89.3%, respectively. KRAS gene mutations were observed in 14.3% of patients by the PNA-PCR clamping method. The NGS method detected more KRAS mutations than the PNA-PCR clamping method: in 25% of patients. Adding the results of KRAS mutation analysis to the cytohistopathological evaluation, the overall diagnostic accuracy of EUS-guided tissue sampling was 96.4%.

CONCLUSIONS

EUS-guided tissue sampling for solid liver masses in the left lobe provided high diagnostic accuracy from cytological and histological evaluations. KRAS mutation analysis provided additional diagnostic yield in patients with inconclusive cytohistopathological results from EUS-guided tissue sampling. The NGS method detected additional KRAS mutations in patients with negative PNA-mediated PCR clamping test results.

Efforts to improve the diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration for pancreatic tumors

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is widely used to obtain a definitive diagnosis of pancreatic tumors. Good results have been reported for its diagnostic accuracy, with high sensitivity and specificity of around 90%; however, technological developments and adaptations to improve it still further are currently underway. The endosonographic technique can be improved when several tips and tricks useful to overcome challenges of EUS-FNA are known. This review provides various techniques and equipment for improvement in the diagnostic accuracy in EUS-FNA.

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.

Endoscopic Ultrasound-Guided Fine-Needle Aspiration of Pancreatic Lesions: A Systematic Review of Technical and Procedural Variables

Endoscopic ultrasound (EUS)-guided tissue acquisition has emerged over the last decade as an invaluable diagnostic tool in approaching the different pancreatic lesions. Given the safety and minimal invasiveness of this approach combined with the high diagnostic yield, it became the standard of care when dealing with different pancreatic pathologies. However, some variables regarding this procedure remain not fully understood. These can influence the diagnostic yield of the procedure and include the presence of the on-site cytopathologist, the type and size of the needle used as well as obtaining aspiration versus core biopsy, the number of passes and the sampling technique, and the role of suction and stylet use among others. We performed a comprehensive literature search using PubMed, Google Scholar, and Embase for studies that assessed these variables. Eligible studies were analyzed using several parameters such as technique and procedure, with the aim of reviewing results from an evidence-based standpoint.

AMG 900, a potent inhibitor of aurora kinases causes pharmacodynamic changes in p-Histone H3 immunoreactivity in human tumor xenografts and proliferating mouse tissues

BACKGROUND

The Aurora family of serine-threonine kinases are essential regulators of cell division in mammalian cells. Aurora-A and -B expression and kinase activity is elevated in a variety of human cancers and is associated with high proliferation rates and poor prognosis. AMG 900 is a highly potent and selective pan-aurora kinase inhibitor that has entered clinical evaluation in adult patients with advanced cancers. In mice, oral administration of AMG 900 blocks the phosphorylation of histone H3 on serine-10 (p-Histone H3), a proximal substrate of aurora-B and inhibits the growth of multiple human tumor xenografts, including multidrug-resistant models.

METHODS

In order to establish a preclinical pharmacokinetic-pharmacodynamic (PK-PD) relationship for AMG 900 that could be translated to the clinic, we used flow cytometry and laser scanning cytometry detection platforms to assess the effects on p-Histone H3 inhibition in terms of sensitivity, precision, and specificity, in human tumor xenografts in conjunction with mouse skin and bone marrow tissues. Mice with established COLO 205 tumors were administered AMG 900 at 3.75, 7.5, and 15 mg/kg and assessed after 3 hours.

RESULTS

Significant suppression of p-Histone H3 in mouse skin was only observed at 15 mg/kg (p <0.0001), whereas in mouse bone marrow and in tumor a dose-dependent inhibition was achieved at all three doses (p ≤ 0.00015). These studies demonstrate that AMG 900 inhibits p-Histone H3 in tumors and surrogate tissues (although tissues such as skin may be less sensitive for assessing PD effects). To further extend our work, we evaluated the feasibility of measuring p-Histone H3 using fine-needle aspirate (FNA) tumor xenograft biopsies. Treatment with AMG 900 significantly inhibited p-Histone H3 (>99% inhibition, p <0.0001) in COLO 205 tumors. Lastly, we illustrate this LSC-based approach can detect p-Histone H3 positive cells using mock FNAs from primary human breast tumor tissues.

CONCLUSION

Phosphorylation of histone H3 is a useful biomarker to determine the pharmacodynamics (PD) activity of AMG 900. FNA biopsies may be a viable approach for assessing AMG 900 PD effects in the clinic.

Neoplasia in chronic pancreatitis: how to maximize the yield of endoscopic ultrasound-guided fine needle aspiration

When performing endoscopic ultrasound-guided fine needle aspiration (EUS-FNA), identifying neoplasia in the setting of chronic pancreatitis can be technically challenging. The morphology of an ill-defined mass on sonography, presence of calcifications or intervening collaterals, reverberation from a biliary stent, low yield of tissue procurement, and interpretative errors in cytopathology can result in both false-negative and false-positive results. Although these challenges cannot be completely eliminated, elastography or contrast-enhanced imaging can aid in differentiating an inflammatory mass from a neoplasm. Also, performing more passes of FNA, procuring core biopsy material, performing rapid onsite evaluation, conducting ancillary pathology studies, and even repeating the procedure on a different day can aid in improving the diagnostic performance of EUS-FNA. This review provides a concise update and offers practical tips to improving the diagnostic yield of EUS-FNA when sampling solid pancreatic mass lesions in the setting of chronic pancreatitis.

Endoscopic ultrasound guided fine needle tissue acquisition: Where we stand in 2013?

Since its introduction, endoscopic ultrasound (EUS) guided fine needle aspiration and fine needle biopsy have become an indispensable tool for the diagnosis of lesions within the gastrointestinal tract and surrounding organs. It has proved to be an effective diagnostic method with high accuracy and low complication rates. Several factors can influence the accuracy and the diagnostic yield of this procedure including experience of the endosonographer, availability of onsite cytopathology services, the method of cytopathology preparation, the location and physical characteristics of the lesion, sampling techniques and the type and size of the needle used. In this review we will outline the recent studies evaluating EUS-guided tissue acquisition and will provide practical recommendations to maximize tissue yield.

Pitfalls in EUS FNA

Although endoscopic ultrasound (EUS) fine-needle aspiration (FNA) is a safe and accurate procedure, the diagnostic yield varies. Factors contributing to the diagnostic accuracy of EUS FNA include endosonographer and cytopathologist experience, EUS image recognition, accurate FNA targeting of the lesion, proper specimen collection and handling, use of ancillary techniques, and accurate cytologic interpretation. Errors in performance or judgment made before, during, or after the procedure may affect the results of the EUS FNA. The authors discuss the potential pitfalls of EUS FNA and methods to avoid their occurrence to optimize the diagnostic yield, efficiency, and safety of the procedure.

The changing paradigm in EUS-guided tissue acquisition

The diagnostic performance of endoscopic ultrasound-guided fine-needle aspiration is strongly dependent on the availability of an onsite cytopathologist. The diagnosis of some rare tumors may require ancillary testing for which a histologic core biopsy is required. There is increasing interest in evaluating core tissue for molecular markers that may serve as prognostic predictors and targets for focused chemotherapy in patients with cancer. If core tissue can be procured efficiently and reliably at endoscopic ultrasound, this will eliminate the need for an onsite cytopathologist, accurately diagnose tumors that are occasionally missed by fine-needle aspiration cytology, and enable the assessment for molecular markers.

Comparison of endoscopic ultrasonography-guided fine-needle aspiration cytology results with and without the stylet in 3364 cases

BACKGROUND AND AIM

Endoscopic ultrasound-guided fine-needle aspiration cytology (EUS-FNA) is traditionally carried out with the stylet, as it is believed to prevent blockage or contamination of the needle by tissue coming from the gastrointestinal wall. However, this recommendation has not been demonstrated on an empirical basis. The aim of the present study was to compare the yield of EUS-FNA in a very large series of patients with (S+) and without (S-) the stylet.

METHODS

Until 2004, the stylet was used for EUS-FNA in our center. After that, the stylet was never used. The results of all EUS-FNA in solid lesions carried out by one endosonographer with the same needle type were compared before and after stylet use was stopped.

RESULTS

3364 EUS-FNA procedures (in 3078 patients) in solid lesions were included (1483 S+ and 1881 S-). There was no significant difference between the S+ and S- results for any variable other than the number of passes required. The number of passes was significantly lower in the S- group when sampling lymph nodes, wall lesions and when carrying out biopsies through the gastric or rectal wall. However the statistical differences disappeared after controlling for malignancy, location and lesion size.

CONCLUSION

This very large comparative study showed no benefit in diagnostic yield when using the stylet for EUS-FNA.

Diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration for pancreatic cancer: a meta-analysis

BACKGROUND AND OBJECTIVE

EUS-FNA of pancreatic lesion has been put into clinical use widely in many centers. The present meta-analysis was conducted to study the diagnostic role of EUS-FNA in pancreatic cancer.

METHODS

A comprehensive review of study on the precision of EUS-FNA in the diagnosis of pancreatic cancer. A random effects model was used to pool the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR) and diagnostic odds ratio (DOR). A summary receiver-operating characteristic (SROC) was constructed to summarize the overall test performance.

RESULTS

Thirty-one articles were eligible for the meta-analysis. The pooled sensitivity, specificity, PLR, NLR and DOR of EUS-FNA in the diagnosis of pancreatic cancer were 0.89 (95% CI: 0.88-0.90), 0.96 (95% CI: 0.95-0.97), 16.88 (95% CI: 10.63-26.79), 0.13 (95%CI: 0.10-0.16) and 150.80 (95%CI: 95.94-237.03) respectively. In subgroup meta-analysis of the prospective studies, the pooled sensitivity, specificity, PLR, NLR and DOR were 0.91 (95% CI: 0.90-0.93), 0.94 (95% CI: 0.91-0.96), 11.19 (95% CI: 6.36-19.69), 0.10 (95% CI: 0.07-0.15) and 125.22 (62.37-251.41). The area under the curve (AUC) was 0.97, indicating a good performance of overall accuracy.

CONCLUSION

EUS-FNA has the high sensitivity and specificity in differentiating pancreatic cancer. Moreover, it is also a safe diagnostic modality with little complications.

A comparative study of endoscopic ultrasound guided fine needle aspiration with and without a stylet

BACKGROUND

Despite lack of evidence, use of a stylet during endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is assumed to improve the quality and diagnostic yield of specimens.

AIM

The purpose of this study was to compare EUS-FNA specimens obtained with stylet (S+) and without stylet (S-) for: (i) cellularity, contamination, adequacy, and amount of blood and (ii) diagnostic yield of malignancy.

METHODS

Patients who underwent EUS-FNA of solid lesions by two experienced endosonographers at a tertiary referral center using a 22-gauge FNA needle with suction were included. Stylet was used for all EUS-FNA procedures performed between January 2006 and September 2007 and no stylet was used between October 2007 and April 2009 allowing comparison between the two techniques. Cytology slides were retrieved, de-identified and evaluated by two experienced cytopathologists blinded to FNA technique. Slides were evaluated for cellularity, degree of contamination, adequacy, amount of blood and cytologic diagnosis. Fisher's exact and unpaired t-test were used for comparative analysis.

RESULTS

A total of 162 patients with 228 lesions were included. FNA of 106 and 122 lesions each was performed in the S+ and S- groups, respectively. FNA sites included pancreas [41 (18%)], lymph node [125 (55%)], liver [20 (9%)], adrenal [21 (9%)] and others [21 (9%)]. No significant differences in the cellularity (P=0.37), contamination (P=0.18), significant blood (P=0.42) and adequacy of specimen (P=0.45) were found between S+ and S- specimens. There was no statistically significant difference in the diagnostic yield of malignant lesions (P=0.48).

CONCLUSIONS

The use of stylet during FNA does not appear to confer any advantage with regards to the adequacy of specimen or diagnostic yield of malignancy.

A prospective, single-blind, randomized, controlled trial of EUS-guided FNA with and without a stylet

BACKGROUND

Most endosonographers use an EUS needle with an internal stylet during EUS-guided FNA (EUS-FNA). Reinserting the stylet into the needle after every pass is tedious and time-consuming, and there are no data to suggest that it improves the quality of the cytology specimen.

OBJECTIVE

To compare the samples obtained by EUS-FNA with and without a stylet for (1) the degree of cellularity, adequacy, contamination, and amount of blood and (2) the diagnostic yield of malignancy.

DESIGN

Prospective,single-blind, randomized, controlled trial.

SETTING

Two tertiary care referral centers.

PATIENTS

Patients referred for EUS-FNA of solid lesions.

INTERVENTION

Patients underwent EUS-FNA of the solid lesions, and 2 passes each were made with a stylet and without a stylet in the needle. The order of the passes was randomized, and the cytopathologists reviewing the slides were blinded to the stylet status of passes.

MAIN OUTCOME MEASUREMENTS

Degree of cellularity, adequacy, contamination, amount of blood, and the diagnostic yield of malignancy in the specimens.

RESULTS

A total of 101 patients with 118 lesions were included in final analysis; 236 FNA passes were made, each with and without a stylet. No significant differences were seen in the cellularity (P = .98), adequacy of the specimen (P = .26), contamination (P = .92), or significant amount of blood (P = .61) between specimens obtained with and without a stylet. The diagnostic yield of malignancy was 55 of 236 specimens (23%) in the with-stylet group compared with 66 of 236 specimens (28%) in the without-stylet group (P = .29).

LIMITATIONS

Endosonographers were not blinded to the stylet status of the passes.

CONCLUSIONS

Using a stylet during EUS-FNA does not confer any significant advantage with regard to the quality of the specimen obtained or the diagnostic yield of malignancy. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT 01213290).

Leveraging image cytometry for the development of clinically feasible biomarkers: evaluation of activated caspase-3 in fine needle aspirate biopsies

Quantitation of activated caspases in xenograft models by laser scanning cytometry has demonstrated mechanism-specific biological activity of Anti-Trail Receptor immunoglobulin therapies in situ. These preclinical data confirmed that caspase activation is an early event that precedes tumor regression. To apply this platform for clinical monitoring of caspase activation using fine needle aspirate (FNA) biopsies, additional assay feasibility and validation experiments need be addressed. Furthermore, important instrument parameters should be considered including the maintenance and operation of the cytometer in a controlled state to ensure aspects like data traceability, reliability, and integrity. In the present chapter we describe a method to evaluate caspase activation in Colo205 cells and fine needle aspirate tumors by slide-based, laser scanning cytometry. This approach can be applied to cell cultures, preclinical and clinical fine needle aspirate material.

Feasibility and yield of a new EUS histology needle: results from a multicenter, pooled, cohort study

BACKGROUND

EUS-guided FNA is an efficacious technique for sampling intraintestinal and extraintestinal mass lesions. However, cytology has limitations to its final yield and accuracy, which may be overcome if histological specimens are provided to the pathologist.

OBJECTIVE

To evaluate feasibility, yield, and diagnostic accuracy of a newly developed 19-gauge, fine-needle biopsy (FNB) device.

DESIGN

Multicenter, pooled, cohort study.

SETTING

Five medical centers.

PATIENTS

This study involved 109 consecutive patients with 114 intraintestinal or extraintestinal mass lesions and/or peri-intestinal lymph nodes.

INTERVENTION

EUS-guided FNB (EUS-FNB) with a newly developed, 19-gauge, FNB device.

MAIN OUTCOME MEASUREMENTS

Percentage of cases in which pathologists classified the sample quality as optimal for histological evaluation and the overall diagnostic accuracy compared with a composite criterion-standard diagnosis.

RESULTS

We evaluated 114 lesions (mean [± standard deviation] size 35.1 ± 18.7 mm; 84 malignant [73.7%] and 30 [26.3%] benign). EUS-FNB was technically feasible in 112 lesions (98.24%). Sample quality was adequate for full histological assessment in 102 lesions (89.47%). In 98 cases (85.96%), diagnosis proved to be correct according to criterion-standard diagnosis. Sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy for diagnosis of malignancy were 90.2%, 100%, 100%, 78.9%, and 92.9%, respectively.

LIMITATIONS

Use of a surrogate criterion-standard diagnosis, including clinical follow-up when no surgical specimens were available, mainly in benign diagnoses.

CONCLUSION

Performing an EUS-FNB with a new 19-gauge histology needle is feasible for histopathology diagnosis of intraintestinal and extraintestinal mass lesions, offering the possibility of obtaining a core sample for histological evaluation in the majority of cases, with an overall diagnostic accuracy of over 85%.

Therapeutic endoscopic ultrasound for biliary and pancreatic disorders

The role of endoscopic ultrasound (EUS) has greatly expanded since the first clinical examination performed nearly 30 years ago. The introduction of linear instruments allowed tissue sampling (Kulesza and Eltoum Clin Gastroenterol Hepatol 5:1248-1254, 2007; Levy and Wiersema Gastrointest Endosc 62:417-426, 2005) and therapeutic interventions applications, including celiac plexus and ganglia blockade and neurolysis (Wiersema and Wiersema Gastrointest Endosc 44:656-662, 1996; Levy and Wiersema Gastroenterol Clin North Am, 35:153-165, 2006; Levy et al. Am J Gastroenterol 103:98-103, 2008), pancreatic fluid drainage (Lopes et al. Arq Gastroenterol 45:17-21, 2008; Norton et al. Mayo Clin Proc 76:794-798, 2001; Kruger et al. Gastrointest Endosc 63:409-416, 2006; Seifert et al.: Endoscopy 32:255-259, 2000), cholecystenterostomy (Kwan et al. Gastrointest Endosc 66:582-586, 2007), and delivery of cytotoxic agents (eg, chemotherapy, radioactive seeds, and gene therapy) (Chang et al.: Cancer 88:1325-1335, 2000; Chang Endoscopy 38(Suppl 1):S88-S93, 2006). The continued need to develop less invasive alternatives to surgical and interventional radiologic therapies drove the development of EUS-guided methods for biliary and pancreatic intervention. This article reviews existing data and focuses on established and emerging EUS techniques for accessing and draining the bile and pancreatic ducts.

The prospective randomized, controlled trial of endoscopic ultrasound-guided fine-needle aspiration using 22G and 19G aspiration needles for solid pancreatic or peripancreatic masses

OBJECTIVES

A large-caliber needle such as a 19-gauge needle may help overcome the limitations of a 22-gauge needle by acquiring a larger amount of tissue sample. However, there has been no well-designed comparative study for endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) with a 19-gauge aspiration needle. We conducted this study to compare the diagnostic accuracy of EUS-FNA using a 19-gauge aspiration needle with that using a 22-gauge aspiration needle in patients with solid pancreatic/peripancreatic mass.

METHODS

From March 2007 to April 2008, a total of 117 patients (60 in a 19-gauge needle group and 57 in a 22-gauge needle group) with solid pancreatic/peripancreatic mass were included. EUS-FNA was performed using the standard technique without an on-site cytopathologist. A single, blinded cytopathologist retrospectively evaluated each set of slides.

RESULTS

The diagnostic accuracy by intention-to-treat analysis was not significantly different (19G: 86.7% vs. 22G: 78.9%, P=0.268). However, the diagnostic accuracy by per-protocol analysis, excluding technical failures, was significantly higher in the 19-gauge needle group (94.5% vs. 78.9%, P=0.015). In the treatment-received group that included crossover cases, although the diagnostic accuracy in all cases was not significantly different (86.1% vs. 76.9%, P=0.164), that of body/tail lesion (95.0% vs. 76.7%, P=0.031) and technically successful cases (93.9% vs. 78.1%, P=0.006) were significantly higher in the 19-gauge needle group. On sample quality analysis, the amount of cellular material obtained was significantly higher in the 19-gauge needle group (P=0.033).

CONCLUSIONS

EUS-FNA with a 19-gauge aspiration needle may be a valuable method for the diagnosis of pancreatic/peripancreatic masses when an on-site cytopathologist is not available.

Role of endoscopic ultrasound-guided fine-needle aspiration with flow cytometry to diagnose lymphoma: a single center experience

BACKGROUND AND AIM

The use of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) +/- flow cytometry (FC) for the diagnosis of suspected lymphoma remains controversial. We report our experience and diagnostic yield for EUS +/- FC for suspected lymphoma.

METHODS

Databases were queried for those who underwent EUS-FNA +/- FC for suspected lymphoma. Hospital charts were reviewed to confirm the final cytological diagnosis, follow up and FC results if obtained. The final diagnosis was confirmed by the results of EUS-FNA +/- FC, other biopsy and/or follow up.

RESULTS

In total, 54 patients underwent EUS-FNA of 72 lesions. The final diagnosis of lymphoma was made in 38 of the 54 (70%) patients, and 33 of the 54 (61%) patients relied on EUS-FNA. Cytopathology in 41 patients using EUS-FNA + FC showed lymphoma in 24 patients, atypical lymphoid cells in six and reactive lymph node in 11. In 9 of the 24 with lymphoma by EUS + FC, the diagnosis was confirmed by another diagnostic modality, like surgery, bone marrow biopsy and computed tomography-guided biopsy. Of the six with atypical lymphoid cells, additional diagnostic methods confirmed lymphoma in three. The remaining 13 of the 54 patients underwent EUS-FNA without FC due to insufficient sample (n = 5) or operator choice (n = 8). Cytopathology in these 13 patients without FC showed lymphoma (9), atypical lymphoid cells (3) and reactive node (1). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of EUS-FNA for lymphoma in all 54 patients ranged from 80% to 87%, 92% to 93%, 97%, 60% to 75% and 83% to 89%, respectively.

CONCLUSIONS

EUS-FNA is sensitive and specific for the diagnosis of suspected lymphoma. Confirmatory or further testing should be performed when EUS-FNA with or without FC is indeterminate and or non-diagnostic.

Comparison of EUS-guided FNA and Trucut biopsy for diagnosing and staging abdominal and mediastinal neoplasms

The objective of this study was to evaluate endoscopic ultrasound Trucut biopsy (TCB) specimens and compare these findings to fine needle aspiration (FNA) specimens for the diagnosis of neoplasia. FNA and TCB specimens were reviewed in blinded fashion by a cytopathologist from patients (N = 93) who had EUS-guided FNA and TCB specimens collected between July 2000 and January 2005. Specimens were categorized as nondiagnostic, negative, suspicious for stromal neoplasm, suspicious for malignancy, positive for stromal neoplasm, or positive for malignancy. Standard final diagnosis based on clinical and/or pathologic follow-up was available for 86 of 93 patients. The final diagnoses comprised malignancy (n = 55), stromal neoplasm (n = 19), and benign findings (n = 12). The combination of FNA and TCB results combined were significantly (P < 0.001) more sensitive that FNA alone for the detection of both malignancy (78% vs. 55%) and stromal neoplasia (79% vs. 19%) without a significant change in overall specificity (92% vs. 100%, P = 1.00). A positive FNA specimen with a negative/nondiagnostic TCB result was established in seven patients with malignancy. A positive TCB diagnosis with a negative/nondiagnostic FNA result was noted in five patients with malignancy. A suspicious FNA result was upgraded to positive in conjunction with TCB specimen evaluation in eight patients with malignancy. The results of this study suggest that TCB is a useful adjunctive technique when used in tandem with FNA for malignancy and stromal neoplasia detection. Additional data are needed to firmly establish practice guidelines for the use of EUS-guided TCB specimens in clinical practice.

Intrapancreatic schwannoma diagnosed by endoscopic ultrasound-guided fine-needle aspiration cytology

Schwannoma is a tumor of neuro-ectodermal origin, usually occuring in the head and neck and extremities. A retroperitoneal, and particularly intra-pancreatic presentation is very rare, and poses a clinical and diagnostic challenge. We report a case of a male patient who underwent an Endoscopic Ultrasound-guided Fine Needle Aspiration (EUS-FNA) biopsy of a hypoechoic, intra-pancreatic mass. The onsite cytological evaluation was consistent with a spindle cell neoplasm. Further evaluation, aided by immunohistochemical stains, defined the mass as a Schwannoma. The patient then underwent a pancreaticoduodenectomy and the histopathological diagnosis of the surgical specimen confirmed the cytological diagnosis. To our knowledge, this is the first report of intra-pancreatic Schwannoma diagnosed preoperatively by EUS-FNA cytology.

Endoscopic ultrasound-guided fine-needle aspiration biopsy and trucut biopsy in gastroenterology - An overview

Endoscopic ultrasound (EUS)-guided biopsies are reliable, safe and effective techniques in obtaining samples for cytological or histological examinations either as a primary procedure or in cases where other biopsy techniques have failed. Endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNA), as well as endoscopic ultrasound-guided trucut biopsy (EUS-TCB), has proven to be of significant value in the diagnostic evaluation of benign and malignant diseases, as well as in staging of the malignant tumours of the gastrointestinal tract and of adjacent organs. The diagnostic yield of EUS-guided biopsies depends on site, size and characteristics of target tissues as well as technical and procedural factors (type of needle, biopsy technique and material processing). Other weighting factors include expertise, training and interaction between the endosonographer and cytopathologist. Rapid on-site cytological evaluation has proven to be successful in optimising the diagnostic efficiency of EUS-FNA. A sensible alternative is to collect specimens for histological and immunohistochemical investigations in addition to the cytological smears. EUS-FNA using a 22-gauge needle is successful in harvesting core biopsies in approximately three out of four cases. Therefore, the use of 19-gauge needles for EUS-FNA or EUS-TCB may only be necessary in selected cases. The reproducibility of cytopathological diagnosis among pathologists with special experience in assessing material obtained by EUS-guided biopsies is very high. False-positive diagnosis of malignancy in EUS-guided biopsy is rare. False-negative diagnosis appears with variable frequency depending on the target tissue, technical factors and expertise of the endosonographer and cytopathologist. There are numerous challenges and pitfalls in the differential diagnostic classification of benign and malignant lesions. These problems are related to the characteristics of samples obtained by EUS-guided biopsy, as well as to the multiple diagnoses with similar or overlapping cytological or histological characteristics. The high prognostic and therapeutic relevance of the cytopathological diagnoses resulting from EUS-guided biopsy calls for a shared responsibility of an endosonographer and a cytopathologist.

NOTES: human experience

Human natural orifice translumenal endoscopic surgery (NOTES) is already being reported from numerous centers, and the results seem promising. There are key issues to be addressed and benefits over traditional safe procedures need to be demonstrated. Interestingly, however, human NOTES seem to be progressing at a fast pace compared with the evolution of surgical procedures or techniques described previously. This article examines the current status of NOTES in humans, the challenges, and the implications on the future of minimal access surgery.