High single-pass diagnostic yield of a new 25-gauge core biopsy needle for EUS-guided FNA biopsy in solid pancreatic lesions

Prospective evaluation of new 22 gauge endoscopic ultrasound core needle using capillary sampling with stylet slow-pull technique for intra-abdominal solid masses

GOALS

The aim of this study was to evaluate the adequacy and diagnostic yield of the histologic core obtained with a 22 G endoscopic ultrasound histology needle using capillary sampling with stylet slow-pull technique without on-site cytopathologist.

BACKGROUND

No standard technique for new EUS histology needle has been established.

STUDY

A total of 125 consecutive patients with intra-abdominal solid masses were enrolled prospectively between October 2011 and March 2013. EUS-guided fine needle biopsy (EUS-FNB) with a 22 G histology needle using capillary sampling with stylet slow-pull technique was performed.

RESULTS

A total of 133 EUS-FNB procedures targeting the pancreas, lymph node, retroperitoneal mass, ampulla of Vater, gallbladder, common bile duct, duodenum, and liver were performed in 125 patients. EUS-FNB was technically feasible in all cases, and a visible core was obtained in 128 cases (96%). Histologic core specimens suitable for pathologic assessment were reported in 111 cases (83%). There were no procedure-related adverse events. According to the determinants of malignancy with EUS-FNB, the sensitivity, specificity, positive and negative predictive values, and accuracy were 85%, 98%, 99%, 77%, and 89%, respectively. In addition, histologic architecture with or without immunohistochemical staining of the core biopsy specimens was useful for pathologic confirmation in 101 cases (76%).

CONCLUSIONS

A 22 G EUS-FNB using capillary sampling with stylet slow-pull technique showed a high diagnostic yield and histologic core acquisition for the histologic diagnosis of various intra-abdominal masses without an on-site cytopathologist. Furthermore, a histologic core with or without immunohistochemical staining was helpful for clinical decision making in 76% of the intra-abdominal solid masses.

PDX-1 mRNA expression in endoscopic ultrasound-guided fine needle cytoaspirate: perspectives in the diagnosis of pancreatic cancer

BACKGROUND AND AIMS

Endoscopic ultrasound-guided fine needle aspiration is routinely used in the diagnostic work up of pancreatic cancer but has a low sensitivity. Studies showed that Pancreatic Duodenal Homeobox-1 (PDX-1) is expressed in pancreatic cancer, which is associated with a worse prognosis. We aimed to verify whether the assessment of PDX-1 in endoscopic ultrasound-guided fine needle aspiration samples may be helpful for the diagnosis of pancreatic cancer.

METHODS

mRNA of 54 pancreatic cancer and 25 cystic lesions was extracted. PDX-1 expression was assessed by Real-Time PCR.

RESULTS

In all but two patients with pancreatic cancer, PDX-1 was expressed and was found positive in 7 patients with pancreatic cancer in which cytology was negative. The positivity was associated with a probability of 0.98 (95% CI 0.90-1.00) of having cancer and the negativity with one of 0.08 (95% CI 0.01-0.27). The probability of cancer rose to 1.00 (95% CI 0.97-1.00) for patients positive to both PDX-1 and cytology and fell to 0.0 (95% CI 0.00-0.15) in patients negative for both.

CONCLUSIONS

PDX-1mRNA is detectable in samples of pancreatic cancer. Its quantification may be helpful to improve the diagnosis of pancreatic cancer.

25-gauge histology needle versus 22-gauge cytology needle in endoscopic ultrasonography-guided sampling of pancreatic lesions and lymphadenopathy

BACKGROUND AND STUDY AIMS

A new 25-gauge (G) endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) device (EchoTip ProCore; Cook Medical, Bloomington, Indiana, USA) has been developed, which features a hollowed-out reverse bevel to trap core samples. However, data on the differences between the diagnostic yield of the 25G EchoTip ProCore and that of a 22G standard needle are limited.

PATIENTS AND METHODS

This pilot study included 27 patients referred during an 11-month period for EUS-FNA of pancreatic masses and enlarged lymph nodes adjacent to the upper gastrointestinal tract. Each lesion was punctured once by both a 25G EchoTip ProCore needle and a 22G standard needle (EchoTip; Cook Medical) with capillary sampling. Blinded histocytologic analyses were conducted. The final diagnosis was based on FNA findings of malignant cells, pathologic analysis of the surgical specimen, and/or radiologic and clinical follow-up of at least 7 months.

RESULTS

A total of 28 EUS-FNA procedures targeting masses of the pancreas (n = 19) and lymph nodes (n = 9) were performed. No complications were encountered. Single-pass sensitivity rates for pancreatic and lymph node malignancy were equal for the needle types: 89.5 % (95 %CI 66.82 - 98.39) and 66 % (95 %CI 24.1 - 94), respectively. There were no significant differences between the needles in terms of EUS visualization (P = 0.125), amount of blood contamination (P = 0.705), macroscopic quantity of the material (P = 0.858), quality of the cytology (P = 0.438), and adequacy and accuracy of the cell block material (P = 0.220).

CONCLUSIONS

Both needles were safe and successful in terms of a high diagnostic yield, with similar histocytologic results. The results of this study were presented at Digestive Disease Week (DDW) 2014, Chicago, Illinois. This trial was registered at ClinicalTrials.gov (B027201316271).

Bench-top testing of suction forces generated through endoscopic ultrasound-guided aspiration needles

BACKGROUND

Adequate needle size and tissue acquisition techniques for endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) need further elucidation. Moreover, the actual negative pressure and suction forces of FNA needles remain unknown. We evaluated the suction forces of 19-gauge, 22-gauge, and 25-gauge conventional FNA needles and side hole aspiration needles using conventional negative pressure and the slow pull technique.

METHODS

Using a manometer, we determined the mean (SD) negative pressure and suction force for needle gauge, aspiration volume, and aspiration technique. We also evaluated the time to reach the maximum negative pressure.

RESULTS

Suction force was comparatively higher in the 19-gauge needle when 50 ml of negative pressure was applied. Suction force using the slow pull method was very weak at 5% of pressure found with conventional methods. With the use of a 20-ml syringe, the time to reach the maximum negative pressure was 4 s in the 19-gauge needle, 11 s in the 22-gauge needle, and 80 s in the 25-gauge needle.

CONCLUSIONS

Bench-top testing showed that suction force increases with a larger gauge needle and larger aspiration volume. The slow pull method produces a very weak suction force. The time to reach the maximum negative pressure was longest in the 25-gauge needle.

Macroscopic on-site quality evaluation of biopsy specimens to improve the diagnostic accuracy during EUS-guided FNA using a 19-gauge needle for solid lesions: a single-center prospective pilot study (MOSE study)

BACKGROUND

Although rapid on-site cytologic evaluation provides high efficacy of EUS-guided FNA (EUS-FNA), its availability is limited. Alternatively, macroscopic on-site quality evaluation (MOSE) may increase the efficacy of EUS-FNA.

OBJECTIVE

To assess the efficacy of MOSE in estimating the adequacy of histologic core specimens obtained by EUS-FNA using a standard 19-gauge needle (19GN) for solid lesions.

DESIGN

A prospective pilot study.

SETTING

Tertiary-care referral center.

PATIENTS

One hundred patients with solid lesions (n = 111 lesions).

INTERVENTIONS

EUS-FNA using 19GN MAIN OUTCOME MEASUREMENTS: The relation of a macroscopic visible core (MVC) in the FNA specimens on MOSE with histologic core and the diagnostic yields were studied.

RESULTS

The feasibility of EUS-FNA using a 19GN was 99%. The final diagnoses were malignancy in 83 lesions and benign in 28. MOSE revealed MVC in 91.1% with the median length of 8 mm. Histologic core was confirmed in 78.9%. The receiver-operating characteristic curve of the length of MVC for the presence of histologic core showed the cut-off MVC length of 4 mm with area under the curve of .893. Comparisons of per-pass diagnostic yields showed significantly superior histologic, cytologic, and overall diagnostic yields in MVC ≥ 4 mm as compared with <4 mm. The multivariate analysis for false-negative pass identified lesion in the pancreas and MVC < 4 mm as significant risk factors. No adverse events were seen.

LIMITATIONS

Single center, limited operators

CONCLUSION

MVC of ≥4 mm on MOSE can be an indicator of specimen adequacy and can improve diagnostic yield; however, additional FNA may be recommended for pancreatic lesions. (

CLINICAL TRIAL REGISTRATION NUMBER

UMIN000010417.).

The 25-gauge EUS-FNA needle: Good for on-site but poor for off-site evaluation? Results of a randomized trial

BACKGROUND

When on-site cytopathology support is not available, EUS-guided fine needle aspiration (EUS-FNA) is performed for cell-block preparation to allow off-site interpretation.

OBJECTIVE

To identify the number of passes required to obtain a diagnostic cell block by using a 25-gauge needle for sampling pancreatic masses.

DESIGN

Randomized trial.

SETTING

Tertiary care hospital.

PATIENTS

Sixty-two patients with solid pancreatic mass lesions.

INTERVENTIONS

EUS-FNA was performed by using a 25-gauge needle. After establishing a preliminary on-site diagnosis, patients were randomized to 2 or 4 FNA passes for a cell block. A cell block was evaluated by a pathologist blinded to on-site interpretation for the presence of a tissue pellet, histological core tissue size, and diagnostic accuracy.

MAIN OUTCOME MEASUREMENTS

To determine the number of passes required to obtain a diagnostic cell block with a 25-gauge FNA needle.

RESULTS

Sixty-two patients were randomized to undergo either 2 (n = 31) or 4 (n = 31) FNA passes for a cell block. Before randomization, an on-site diagnosis was established in all 62 patients (100%). The final diagnosis was adenocarcinoma in 45 (72.6%), neuroendocrine/other tumor in 7 (11.3%), and chronic pancreatitis in 10 (16.1%). There was no difference in the presence of a tissue pellet (93.5 vs 96.8%; P = .99), the median size of the histological core (0.006 vs 0.05 mm(2); P = .12), or the presence of a diagnostic cell block (80.6 vs 80.6%; P = .99) between patients randomized to 2 or 4 FNA passes, respectively.

LIMITATIONS

Only pancreatic masses were evaluated.

CONCLUSIONS

The 25-gauge FNA needle yielded a diagnostic cell block in only 81% of patients, irrespective of whether 2 or 4 FNA passes were performed. These findings have important implications for centers without on-site cytopathology services. (Clinical trial registration number NCT01809028.).

Management of borderline resectable pancreatic cancer

Borderline resectable pancreatic cancers are those that, although technically resectable, are at high risk for margin-positive resection following surgery de novo. Generally, such cancers are characterized by localized primary tumors that involve the mesenteric vasculature to a limited degree and that may require venous or hepatic arterial resection at pancreatectomy. In this article, we review diagnosis and staging algorithms, pretreatment strategies, and multidisciplinary treatment protocols for patients with this stage of disease. The rationale for and results following treatment with neoadjuvant chemotherapy and chemoradiation and subsequent surgical resection of the primary tumor are described in detail and existing data are reviewed.

Endoscopic ultrasound-guided fine-needle biopsy of small solid pancreatic lesions using a 22-gauge needle with side fenestration

BACKGROUND

Early detection of small pancreatic cancer is important because expected survival is markedly better for tumors ≤ 2 cm. A new endoscopic ultrasound-(EUS) guided biopsy needle with side fenestration has been recently developed to enable fine-needle biopsy (FNB) under EUS guidance. The aim of this study was to evaluate the outcome of EUS-FNB using a 22-gauge ProCore needle in solid pancreatic lesions ≤ 2 cm, in terms of diagnostic accuracy and yield.

METHODS

From January 2011 to December 2012, all consecutive EUS-guided tissue sampling of small pancreatic lesions (≤ 2 cm) were performed using 22-gauge ProCore needles; the data of these patients were analyzed retrospectively.

RESULTS

Sixty-eight patients with a mean age of 65.7 years were included. The mean lesion size was 16.5 mm (range 5-20). None of the patients developed complications. On pathological examination, the tissue retrieved was judged adequate in 58 out of 68 cases (85.3 %) and the presence of a tissue core was recorded in 36 out of 68 cases (52.9 %). The overall sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 80, 100, 100, 40, and 82 %, respectively.

CONCLUSION

Our results suggested that EUS-FNB of small pancreatic lesions using a 22-gauge ProCore needle is effective and safe, and supports our hypothesis that EUS-FNB is highly useful in establishing the nature of small pancreatic lesions.

Fine-needle biopsy: should this be the first choice in endoscopic ultrasound-guided tissue acquisition?

Endoscopic ultrasound (EUS)-guided tissue acquisition is an indispensable technique for the diagnosis of many diseases of the gastrointestinal tract and adjacent structures. EUS-guided fine-needle aspiration (EUS-FNA) is known for its high accuracy and low complication rate. However, the outcome of EUS-FNA highly depends on several factors such as the location and characteristics of the lesion, endosonographer's experience, technique of sampling and sample preparation, type and size of the needle used, and presence of a cytopathologist for rapid on-site examination. EUS-guided fine-needle biopsy is useful to obtain core tissue samples with relatively fewer passes. Aspiration of core tissue with preserved architecture is beneficial for the diagnosis of certain diseases and the performance of ancillary testing such as tumor molecular profiling. Issues related to needle size, type, and their acquired samples for cytologic and histologic evaluation are discussed here.

Diagnostic efficacy of cell block immunohistochemistry, smear cytology, and liquid-based cytology in endoscopic ultrasound-guided fine-needle aspiration of pancreatic lesions: a single-institution experience

Background

The diagnostic efficiency of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) cytology varies widely depending on the treatment method of the specimens. The present study aimed to evaluate the diagnostic efficacy of cell block (CB) immunohistochemistry, smear cytology (SC), and liquid-based cytology (LBC) in patients with pancreatic lesions without consulting an on-site cytopathologist.

Methods

This study prospectively enrolled 72 patients with pancreatic lesions. The EUS-FNA specimens were examined by SC, LBC, and CB immunohistochemistry. The diagnostic efficacy of the 3 methods was then compared. Patients’ final diagnosis was confirmed by surgical resection specimens, diagnostic imaging, and clinical follow-up.

Results

Our results included 60 malignant and 12 benign pancreatic lesions. The diagnostic sensitivity (90%), negative predictive value (66.7%), and accuracy (91.7%) of CB immunohistochemistry were significantly higher than those of SC (70.0%, 30.0%, and 75.0%, respectively) and LBC (73.3%, 31.6%, and 77.8%, respectively) (all P<0.05). The combination of CB and SC, or CB and LBC, did not significantly increase the efficacy compared to CB immunohistochemistry alone.

Conclusion

Our findings suggest that in the absence of an on-site cytopathologist, CB immunohistochemistry on EUS-FNA specimens offers a higher diagnostic efficacy in patients with pancreatic lesions than does SC and LBC.

Endoscopic ultrasound in the diagnosis and treatment of pancreatic disease

Endoscopic ultrasound (EUS) is an important part of modern gastrointestinal endoscopy and now has an integral role in the diagnostic evaluation of pancreatic diseases. Furthermore, as EUS technology has advanced, it has increasingly become a therapeutic procedure, and the prospect of multiple applications of interventional EUS for the pancreas is truly on the near horizon. However, this review focuses on the established diagnostic and therapeutic roles of EUS that are used in current clinical practice. In particular, the diagnostic evaluation of acute pancreatitis, chronic pancreatitis, cystic pancreatic lesions and solid masses of the pancreas are discussed. The newer enhanced imaging modalities of elastography and contrast enhancement are evaluated in this context. The main therapeutic aspects of pancreatic EUS are then considered, namely celiac plexus block and celiac plexus neurolysis for pain control in chronic pancreatitis and pancreas cancer, and EUS-guided drainage of pancreatic fluid collections.

High-quality endoscopic ultrasound-guided fine needle aspiration tissue acquisition

Endoscopic ultrasound-guided fine needle aspiration is a multistep procedure that involves proper clinical indication, correct selection of needles, adapting evidence-based techniques such as the fanning maneuver and not routinely using suction or the stylet for tissue sampling, and establishing reliable cytopathology support. Integrating cytopathology in the training curriculum and developing a more flexible platform of needles and echoendoscopes are likely to further advance the field of endosonography. This review aims to summarize the technical issues that are key to performing high-quality endoscopic ultrasound-guided fine needle aspiration.

Slow pull versus suction in endoscopic ultrasound-guided fine-needle aspiration of pancreatic solid masses

BACKGROUND

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of pancreatic masses is an established procedure for obtaining a pathological specimen. However, application of suction during EUS-FNA is still controversial and the efficacy of the slow-pull technique was recently reported for new core biopsy needles.

AIM

The purpose of this study was to compare the suction and slow-pull techniques using regular FNA needles.

METHODS

The diagnostic yield of the suction and slow-pull techniques was retrospectively studied for patients who underwent EUS-FNA for pancreatic solid lesions.

RESULTS

A total of 367 passes (181 by suction and 186 by the slow-pull technique) were performed during 97 EUS-FNA procedures for 93 patients with pancreatic solid lesions. The slow-pull technique resulted in lower scores for cellularity (≥2 for 37.5 % vs. 76.7 %) but scores for contamination with blood were lower (≥2 for 25.0 % vs. 66.7 %) and sensitivity of diagnosis of malignancy was higher (90.0 % vs. 67.9 %) when a 25-gauge FNA needle was used. There were no significant differences between the two techniques when a 22-gauge needle was used. In multivariate analysis of 82 cases with malignancy, the slow-pull technique (odds ratio (OR) 1.92, P = 0.028), tumor size ≥25 mm (OR 4.64, P < 0.001), and tumor location in the body or tail (OR 2.82, P < 0.001) were associated with greater sensitivity.

CONCLUSION

The slow-pull technique was associated with less contamination with blood and can potentially increase the diagnostic yield compared with the suction technique in EUS-FNA of pancreatic solid masses, especially with a 25-gauge FNA needle.

Endoscopic ultrasound-guided fine needle aspiration: How to obtain a core biopsy?

Endoscopic ultrasound (EUS)-guided fine needle aspiration has emerged as the procedure of choice to obtain samples to reach a definitive diagnosis of lesions of the gastrointestinal tract and of adjacent organs. The obtainment of a tissue core biopsy presents several advantages that can substantially contribute to the widespread diffusion of EUS utilization in the community and in countries where cytology expertise may be difficult to be achieved. This article will review the EUS-guided fine needle biopsy techniques developed so far, the clinical results, their limitations as well as their future perspective.

When to puncture, when not to puncture: Submucosal tumors

Subepithelial masses of the gastrointestinal (GI) tract are a frequent source of referral for endosonographic evaluation. Subepithelial tumors most often appear as protuberances in the GI tract with normal overlying mucosa. When there is a need to obtain a sample of the mass for diagnosis, endoscopic ultrasound (EUS) - guided fine-needle aspiration (FNA) is superior to other studies and should be the first choice to investigate any subepithelial lesion. When the decision is made to perform EUS-guided FNA several technical factors must be considered. The type and size of the needle chosen can affect diagnostic accuracy, adequacy of sample size and number of passes needed. The use of a stylet or suction and a fanning or standard technique during EUS-guided FNA are other factors that must be considered. Another method proposed to improve the efficacy of EUS-guided FNA is having an on-site cytopathologist or cytotechnician. Large or well-differentiated tumors may be more difficult to diagnose by standard EUS-FNA and the use of a biopsy needle can be used to acquire a histopathology sample. This can allow preservation of tissue architecture and cellularity of the lesion and may lead to a more definitive diagnosis. Alternatives to FNA such as taking bite-on-bite samples and endoscopic submucosal resection (ESMR) have been studied. Comparison of these two techniques found that ESMR has a significantly higher diagnostic yield. Most complications associated with EUS-FNA such as perforation, infection and pancreatitis are rare and the severity and incidence of these adverse events is not known. Controversy exists as to the optimal method in which to perform EUS-FNA and larger prospective trials are needed.

Techniques for endoscopic ultrasound-guided fine-needle biopsy

Although endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is the method of choice to obtain samples to reach definitive diagnosis of lesions of the gastrointestinal tract and of adjacent organs, it cannot fully characterize certain neoplasms. The lack of cytology expertise has hindered the dissemination of EUS, limiting its widespread use. The obtainment of a tissue specimen through EUS fine-needle biopsy (EUS-FNB) may overcome the limitations of EUS-FNA. EUS-FNB is expected to move the practice of EUS from cytology to histology, expanding the use of EUS and facilitating targeted therapies and monitoring of treatment response in a more biologically driven manner.

Endoscopic ultrasound-guided fine needle aspiration and biopsy using a 22-gauge needle with side fenestration in pancreatic cystic lesions

BACKGROUND

Cytologic diagnosis by endoscopic ultrasound-guided fine needle aspiration is associated with low sensitivity and adequacy. A newly designed endoscopic ultrasound-guided fine needle biopsy device, endowed with a side fenestration, is now available.

AIMS

We carried out a study with the aim of evaluating the feasibility, safety, and diagnostic yield of the 22-gauge needle with side fenestration for endoscopic ultrasound fine needle aspiration and biopsy of pancreatic cystic lesions.

METHODS

58 patients with 60 pancreatic cystic lesions consecutively referred for endoscopic ultrasound guided-fine needle aspiration were enrolled in a prospective, dual centre study, and underwent fine needle aspiration and biopsy with the 22-gauge needle with side fenestration.

RESULTS

Fine needle aspiration and biopsy was technically feasible in all cases. In 39/60 (65%) pancreatic cystic lesions, the specimens were adequate for cyto-histologic assessment. In lesions with solid components, and in malignant lesions, adequacy was 94.4% (p = 0.0149) and 100% (p = 0.0069), respectively. Samples were adequate for histologic evaluation in 18/39 (46.1%) cases. There were only 2 (3.3%) mild complications.

CONCLUSIONS

Fine needle aspiration and biopsy with the 22-gauge needle with side fenestration is feasible, and superior to conventional endoscopic ultrasound-guided fine needle aspiration cytology from cystic fluid, particularly in pancreatic cystic lesions with solid component or malignancy, with a higher diagnostic yield and with no increase in complication rate.

Endoscopic ultrasound-guided tissue acquisition

Endoscopic ultrasound (EUS) is an indispensable tool for tissue acquisition in patients with gastrointestinal tumors. While fine-needle aspiration (FNA) has been routinely carried out for establishing tissue diagnosis, the emerging concept of tailoring chemotherapeutic agents based on molecular markers has increased the demand for core tissue procurement by means of EUS-guided fine-needle biopsy (EUS-FNB). In addition, FNB may offset the limitations of FNA wherein the diagnostic sensitivity is incumbent on the availability of an onsite cytopathologist. Given the increasing number of procedures being done, developing a unit-specific algorithmic approach for needle selection is important to improve the procedural efficiency and utilization of resources. Finally, the best outcomes can be attained only by practicing evidence-based techniques, procuring adequate quantity of sample for ancillary studies and processing the specimens appropriately.

Tips to overcome technical challenges in EUS-guided tissue acquisition

The diagnostic yield of EUS-FNA depends on several factors, such as the experience of the endosonographer, the characteristics of the lesion, the clinical status of the patient, the size and type of needles, the methods of specimen preparation, as well as cytopathologist expertise. The endosonographic technique can be improved when several tips and tricks useful to overcome challenges of FNA are known. Technical challenges of FNA are related to the characteristics of the lesion and its surroundings, sonographic imaging, and limitations related to the needle. Several tips and tricks necessary to overcome them are presented in this review.

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.

Tips for endoscopic ultrasound-guided fine needle aspiration of various pancreatic lesions

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is a well-established procedure for diagnosis of pancreatic solid masses. This technique is highly accurate and safe and can be performed uneventfully in most cases. However, factors such as unstable scope position, inappropriate location of the lesion, lesion mobility, and lesion characteristics may complicate the procedure. To overcome such difficulties, it is necessary to select the most suitable needle and consider several technical points according to each situation. We introduce our standard technique for EUS-FNA and provide several tips for ensuring a successful procedure.

Procore and flexible 19 gauge needle can replace trucut biopsy needle?

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is routinely performed for establishing tissue diagnosis in patients with gastrointestinal tumors. The concept of delivering chemotherapy based on molecular markers and the ability to establish a reliable diagnosis in lieu of an onsite cytopathologist has fuelled the recent trend in procuring core tissue by means of EUS-guided fine needle biopsy. To overcome the technical limitations induced by the rigidity of the Trucut biopsy needle, a new ProCore needle with reverse bevel technology has been developed. Recent data suggests that the newly developed flexible 19 gauge needle can also procure core tissue and has easy maneuverability when navigating the transduodenal route. Irrespective of the needles being used, the best clinical outcomes can be attained only by practicing evidence-based techniques, procuring adequate quantity of sample for ancillary studies, and processing the specimens appropriately.