Diagnostic value of liquid-based cytology and smear cytology in pancreatic endoscopic ultrasound-guided fine needle aspiration: A meta-analysis

BACKGROUND Smear cytology(SC)using endoscopic ultrasound-guided fine needle aspiration(EUS-FNA)is the established and traditional choice for diagnosing pancreatic lesions.Liquid-based cytology(LBC)is a novel alternative cytological method,however,the comparative diagnostic efficacy of LBC remains inconclusive.AIM To examine the diagnostic efficacy of LBC and SC for pancreatic specimens obtained through EUS-FNA via a systematic review and meta-analysis.METHODS A systematic literature search was performed using PubMed,EMBASE,the Cochrane Library,and Web of Science.The numbers of true positives,false positives,true negatives,and false negatives for each cytological test(LBC and CS)were extracted from the included studies.The pooled sensitivity and specificity and the area under the summary receiver operating characteristic curve(AUC)were calculated,and the AUC was compared by Tukey's multiple comparisons test.The quality of the included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies II tool.RESULTS A total of 1656 patients in eight studies were included.The pooled sensitivity and specificity and the AUC for LBC were 0.76(95%CI:0.72-0.79),1.00(95%CI:0.98-1.00),and 0.9174,respectively,for diagnosing pancreatic lesions.The pooled estimates for SC were as follows:Sensitivity,0.68(95%CI:0.64-0.71);specificity,0.99(95%CI:0.96-100.00);and AUC,0.9714.Similarly,the corresponding values for LBC combined with SC were 0.87(95%CI:0.84-0.90),0.99(95%CI:0.96-1.00),and 0.9894.Tukey’s multiple comparisons test was used to compare the sensitivities and AUCs of the three diagnostic methods;statistically significant differences were found between the three methods,and LBC combined with SC was superior to both LBC(P<0.05)and SC(P<0.05).The pooled sensitivity and AUC did not change significantly in the sensitivity analysis.CONCLUSION LBC may be sensitive than SC in the cytological diagnosis of pancreatic lesions,however,the superior diagnostic performance of their combination emphasizes their integrated usage in the clinical evaluation of pancreatic lesions.

Endoscopic ultrasound-guided fine needle aspiration in the differentiation of type 1 and type 2 autoimmune pancreatitis

AIM:To investigate the usefulness of endoscopic ultrasound-guided fine needle aspiration(EUS-FNA) in the differentiation of autoimmune pancreatitis(AIP).METHODS:We retrospectively reviewed 47 of 56 AIP patients who underwent EUS-FNA and met the Asian diagnostic criteria.On 47 EUS-FNA specimens,we evaluated the presence of adequate material and characteristic features of lymphoplasmacytic sclerosing pancreatitis(LPSP) and idiopathic duct-centric pancreatitis(IDCP) mentioned in the International Consensus Diagnostic Criteria and examined if these findings make a contribution to the differential diagnosis of type 1 and type 2 AIP.A disposable 22-gauge needle was used for EUS-FNA.RESULTS:Adequate specimens including pancreatic tissue for differentiating AIP from cancer were obtained from 43 of 47 patients who underwent EUSFNA.EUS-FNA was performed from the pancreatic head in 21 cases,which is known to be technically difficult when performed by core biopsy;there was no significant difference in the results compared with pancreatic body-tail.Nine of 47 patients met level 1 findings of LPSP and 5 patients met level 2 findings of LPSP.No one met level 1 findings of IDCP,but 3 patients met level 2 findings of IDCP.Of 10 seronegative cases,2 cases were diagnosed with "definitive type 1 AIP",and 3 cases were diagnosed with "probable type 2 AIP" when considering both the level 2 histological findings and response to steroids.CONCLUSION:EUS-FNA is useful in the differentiation of type 1 and type 2 AIP,particularly in seronegative cases.

Peritoneal dissemination of pancreatic cancer caused by endoscopic ultrasound-guided fine needle aspiration:A case report and literature review

BACKGROUND Endoscopic ultrasound-guided fine needle aspiration(EUS-FNA)is a biopsy technique widely used to diagnose pancreatic tumors because of its high sensitivity and specificity.Although needle-tract seeding caused by EUS-FNA has been recently reported,dissemination of pancreatic cancer cells is generally considered to be a rare complication that does not affect patient prognosis.However,the frequency of dissemination and needle-tract seeding appears to have been underestimated.We present a case of peritoneal dissemination of pancreatic cancer due to preoperative EUS-FNA.CASE SUMMARY An 81-year-old man was referred to the Department of Surgery of our hospital in Japan owing to the detection of a pancreatic mass on computed tomography during medical screening.Trans-gastric EUS-FNA revealed that the mass was an adenocarcinoma;hence laparoscopic distal pancreatectomy with lymphadenectomy was performed.No intraoperative peritoneal dissemination and liver metastasis were visually detected,and pelvic lavage cytology was negative for carcinoma cells.The postoperative surgical specimen was negative for carcinoma cells at the dissected margin and the cut end margin;however,pathological findings revealed adenocarcinoma cells on the peritoneal surface proximal to the needle puncture site,and the cells were suspected to be disseminated via EUSFNA.Hence,the patient received adjuvant therapy with S-1(tegafur,gimeracil,and oteracil potassium);however,computed tomography performed 5 mo after surgery revealed liver metastasis and cancerous peritonitis.The patient received palliative therapy and died 8 mo after the operation.CONCLUSION The indications of EUS-FNA should be carefully considered to avoid iatrogenic dissemination,especially for cancers in the pancreatic body or tail.

Preoperative diagnosis of gastrointestinal stromal tumor by endoscopic ultrasound-guided fine needle aspiration

AIM： to evaluate the role of endoscopic ultrasonographyguided fine needle aspiration （EUS-FNA） in the preoperative diagnosis of gastrointestinal stromal tumor （GIST）.METHODS： From September 2002 to June 2006, Fiftythree consecutive EUS-FNAs of GI tract subepithelial hypoechoic tumors with continuity to proper muscle layer suspected as GIST by standard EUS were evaluated prospectively. The reference standards for the final diagnosis were surgery （n = 31）, or clinical follow-up （n = 22）. Additionally, immunophenotyping of specimens obtained by EUS-FNA and surgical resection specimens were compared.RESULTS： In 2 cases puncture was not performed because of anatomical problems. The collection rate of adequate specimens from the GI tract subepithelial hypoechoic tumor with continuity to proper muscle layer was 82% （42/51）. The diagnostic rate for the tumor less than 2 cm, 2 to 4 cm, and 4 cm or more were 71% （15/21）, 86% （18/21）, and 100% （9/9）,respectively. In 29 surgically resected cases, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of EUS-FNA using immunohistochemical analysis of GIST were 100%（24/24）, 80% （4/5）, 96% （24/25）, 100% （4/4）, and 97% （28/29）, respectively. No major complications were encountered.CONCLUSION： EUS-FNA with immunohistochemical analysis is a safe and accurate method in the pretherapeutic diagnosis of GIST. It should be taken into consideration in decision making, especially in early diagnosis following minimal invasive surgery for GIST.

Identification of biomarkers of human pancreatic adenocarcinomas by expression profiling and validation with gene expression analysis in endoscopic ultrasound-guided fine needle aspiration samples

AIM： To compare gene expression profiles of pancreatic adenocarcinoma tissue specimens, human pancreatic and colon adenocarcinoma and leukemia cell lines and normal pancreas samples in order to distinguish differentially expressed genes and to validate the differential expression of a subset of genes by quantitative real-time RT-PCR （RT-QPCR） in endoscopic ultrasound-guided fine needle aspiration （EUS-guided FNA） specimens.METHODS： Commercially dedicated cancer cDNA macroarrays （Atlas Human Cancer 1.2） containing 1176 genes were used. Different statistical approaches （hierarchical clustering, principal component analysis （PCA） and SAM） were used to analyze the expression data. RT-QPCR and immunohistochemical studies were used for validation of results.RESULTS： RT-QPCR validated the increased expression of LCN2 （lipocalin 2） and for the first time PLAT （tissue-type plasminogen activator or tPA） in malignant pancreas as compared with normal pancreas. Immunohistochemical analysis confirmed the increased expression of LCN2 protein localized in epithelial cells of ducts invaded by carcinoma. The analysis of PLAT and LCN2 transcripts in 12 samples obtained through EUS-guided FNA from patients with pancreatic adenocarcinoma showed significantly increased expression levels in comparison with those found in normal tissues, indicating that a sufficient amount of high quality RNA can be obtained with this technique.CONCLUSION： Expression profiling is a useful method to identify biomarkers and potential target genes. Molecular analysis of EUS-guided FNA samples in pancreatic cancer appears as a valuable strategy for the diagnosis of pancreatic adenocarcinomas.

Usefulness of endoscopic ultrasound-guided fine needle aspiration in the diagnosis of hepatic, gallbladder and biliary tract Lesions

Endoscopic ultrasound(EUS)-guided fine needle aspira-tion(FNA) of the liver is a safe procedure in the diag-nosis and staging of hepatobiliary malignancies with a minimal major complication rate. EUS-FNA is useful for liver lesions poorly accessible to other imaging modali-ties of the liver. EUS-guided FNA of biliary neoplasia and malignant biliary stricture is superior to the con-ventional endoscopic brushing and biopsy.

Randomized controlled study of the safety and efficacy of nitrous oxide-sedated endoscopic ultrasound-guided fine needle aspiration for digestive tract diseases

AIM To evaluate the efficacy and safety of nitrous oxidesedated endoscopic ultrasound-guided fine needle aspiration. METHODS Enrolled patients were divided randomly into an experimental group(inhalation of nitrous oxide) and a control group(inhalation of pure oxygen) and heart rate, blood oxygen saturation, blood pressure, electrocardiogram(ECG) changes, and the occurrence of complications were monitored and recorded. All patients and physicians completed satisfaction questionnaires about the examination and scored the process using a visual analog scale. RESULTS There was no significant difference in heart rate, blood oxygen saturation, blood pressure, ECG changes, or complication rate between the two groups of patients(P > 0.05). However, patient and physician satisfaction were both significantly higher in the nitrous oxide compared with the control group(P < 0.05).CONCLUSION Nitrous oxide-sedation is a safe and effective option for patients undergoing endoscopic ultrasound-guided fine needle aspiration.

Push vs pull method for endoscopic ultrasound-guided fine needle aspiration of pancreatic head lesions: Propensity score matching analysis

AIM To evaluate the efficacy of endoscopic ultrasoundguided fine needle aspiration(EUS-FNA) of pancreatic head cancer when pushing(push method) or pulling the echoendoscope(pull method).METHODS Overall, 566 pancreatic cancer patients had their first EUS-FNA between February 2001 and December 2017. Among them, 201 who underwent EUS-FNA for pancreatic head lesions were included in this study. EUS-FNA was performed by the push method in 85 patients, the pull method in 101 patients and both the push and pull methods in 15 patients. After propensity score matching(age, sex, tumor diameter, and FNA needle), 85 patients each were stratified into the push and pull groups. Patient characteristics and EUSFNA-related factors were compared between the two groups.RESULTS Patient characteristics were not significantly different between the two groups. The distance to lesion was significantly longer in the push group than in the pull group(13.9 ± 4.9 mm vs 7.0 ± 4.9 mm, P < 0.01). The push method was a significant factor influencing the distance to lesion(≥ median 10 mm)(P < 0.01). Additionally, tumor diameter ≥ 25 mm(OR = 1.91, 95%CI: 1.02-3.58, P = 0.043) and the push method(OR = 1.91, 95%CI: 1.03-3.55, P = 0.04) were significant factors contributing to the histological diagnosis of malignancy.CONCLUSION The pull method shortened the distance between the endoscope and the lesion and facilitated EUS-FNA of pancreatic head cancer. The push method contributed to the histological diagnosis of pancreatic head cancer using EUS-FNA specimens.

Retroperitoneal germ cell tumor diagnosed by endoscopic ultrasound-guided fine needle aspiration

Isolated extragonadal germ cell tumors can be primary in nature or metastatic from a burned out testicular cancer.Accurate diagnosis is critical as appropriate therapy can be highly curative.We present the case of an isolated extragonadal germ cell tumor in the retroperitoneum diagnosed by endoscopic ultrasound-guided fi ne needle aspiration.This case underscores the importance of considering germ cell tumors in the differential diagnosis of an unexplained retroperitoneal mass,particularly since immunophenotypic staining may be necessary to establish the diagnosis.2010 Baishideng.All rights reserved.

Endoscopic Ultrasound-Guided Fine Needle Aspiration Cytology of Gastrointestinal Tract Tumors and Related Organs: Predictive Factors for Accurate Cytopathological Diagnosis

Background: Endoscopic ultrasonography (EUS) is well-established, highly accurate clinical diagnostic test for detection and staging of gastrointestinal tract lesions and related organs. The addition of endoscopic guided fine needle aspiration cytology (EUS-FNAC) has improved the performance characteristics of EUS. Aim: Evaluate the validity of EUS-FNAC in diagnosis of gastrointestinal tract lesions and related organs and assess predictive factors for an accurate EUS-FNAC diagnosis. Methods: Our study included cytological sampling from one hundred sixty-six lesions obtained from gastrointestinal tract and related organs. Factors affecting EUS-FNA accuracy were analyzed. The histopathological results or clinical follow-up were used as the gold standard method. Results: Samples were obtained from: pancreatic masses (n = 80), gastric masses (n = 34), lymph nodes (n = 22), hepatobiliary masses (n = 18) and rectal masses (n = 2). Statistical analysis of sensitivity, specificity, Positive Predictive Value, Negative Predictive Value, and diagnostic accuracy of EUS alone was 80.4%, 51.6%, 75.8%, 76.2% and 75.9% respectively. The sensitivity, specificity, positive predictive value and negative predictive value of EUS-FNAC are 78.8%, 96.8%, 97.6% and 73.2% respectively. Addition of FNAC to EUS improved diagnostic accuracy to 85.5%. Positive statistical association was present between cytological adequacy and adequate cell block preparations, larger lesion size, presence of rapid on site evaluation (ROSE) and obtaining at least two passes from target lesion. Conclusions: EUS is valuable diagnostic and cost effective tool for gastrointestinal tract lesions and related organs when combined with FNAC.

Endoscopic ultrasound-guided fine-needle aspiration pancreatic adenocarcinoma samples yield adequate DNA for next-generation sequencing:A cohort analysis

BACKGROUND Genetic tests are increasingly performed for the management of unresectable pancreatic cancer.For genotyping aimed samples current guidelines recommend using core specimens,although based on moderate quality evidence.However,in clinical practice among the endoscopic ultrasound(EUS) guided tissue acquisition methods,fine needle aspiration(FNA) is the most widely performed.AIM To assess the adequacy for next generation sequencing(NGS) of the DNA yielded from EUS-FNA pancreatic adenocarcinoma(PDAC) samples.METHODS Between November 2018 and December 2021,105 patients with PDAC confirmed by EUS-FNA were included in the study at our tertiary gastroenterology center.Either 22 gauge(G) or 19G FNA needles were used.One pass was dedicated to DNA extraction.DNA concentration and purity(A260/280,A260/230) were assessed by spectrophotometry.We assessed the differences in DNA parameters according to needle size and tumor characteristics(size,location) and the adequacy of the extracted DNA for NGS(defined as A260/280 ≥ 1.7,and DNA yield:≥ 10 ng for amplicon based NGS,≥ 50 ng for whole exome sequencing [WES],≥ 100 ng for whole genome sequencing [WGS]) by analysis of variance and ttest respectively.Moreover,we compared DNA purity parameters across the different DNA yield categories.RESULTS Our cohort included 49% male patients,aged 67.02 ± 8.38 years.The 22G needle was used in 71%of the cases.The DNA parameters across our samples varied as follows:DNA yield:1289 ng(inter quartile range:534.75-3101),A260/280 = 1.85(1.79-1.86),A260/230 = 2.2(1.72-2.36).DNA yield was > 10 ng in all samples and > 100 ng in 93% of them(one sample < 50 ng).There were no significant differences in the concentration and A260/280 between samples by needle size.Needle size was the only independent predictor of A260/230 which was higher in the 22G samples(P =0.038).NGS adequacy rate was 90% for 19G samples regardless of NGS type,and for 22G samples it reached 89% for WGS adequacy and 91% for WES and amplicon based NGS.Samples with DNA yield > 100 ng had significantly higher A260/280(1.89 ± 0.32 vs 1.34 ± 0.42,P = 0.013).Tumor characteristics were not corelated with the DNA parameters.CONCLUSION EUS-FNA PDAC samples yield DNA adequate for subsequent NGS.DNA amount was similar between 22G and 19G FNA needles.DNA purity parameters may vary indirectly with needle size.

Can the wet suction technique change the efficacy of endoscopic ultrasound-guided fine-needle aspiration for diagnosing autoimmune pancreatitis type 1? A prospective single-arm study

BACKGROUND Other than surgery,endoscopic ultrasound-guided fine-needle aspiration(EUSFNA)is the only procedure for histologically diagnosing autoimmune pancreatitis(AIP).However,adequate specimens are difficult to obtain.Recently,more adequate specimens were reported to be obtained with EUS-FNA with a wet suction technique(WEST)than with conventional EUS-FNA.AIM To histologically diagnose AIP by EUS-FNA with a WEST.METHODS Eleven patients with possible type 1 AIP between February 2016 and August 2018 underwent EUS-FNA with a WEST(WEST group),with four punctures by 19 or 22 G needles.As a historical control,23 type 1 AIP patients who underwent no fewer than four punctures with 19 or 22 G needles were enrolled(DRY group).Patient characteristics and histological findings were compared between the two groups.RESULTS Three histopathological factors according to the International Consensus Diagnostic Criteria were significantly greater in the WEST group than the DRY group[lymphoplasmacytic infiltrate without granulocytic infiltration:9(81.8%)vs 6(26.1%),P=0.003,storiform fibrosis:5(45.5%)vs 1(4.3%),P=0.008,abundant(>10 cells/HPF)IgG4-positive cells:7(63.6%)vs 5(21.7%),P=0.026].Level 1 or level 2 histopathological findings were observed more often in the WEST group than in the DRY group[8(72.7%)vs 3(13.0%),P=0.001].CONCLUSION EUS-FNA with a WEST was more successful than standard EUS-FNA in histologically diagnosing AIP.

Ultrasound-guided vs endoscopic ultrasound-guided fine-needle aspiration for pancreatic cancer diagnosis

AIM: To clarify the effectiveness and safety of endo- scopic ultrasound-guided fine-needle aspiration (EUS-FNA) for the diagnosis of pancreatic cancer (PC). METHODS: Patients who were diagnosed with unresectable, locally advanced or metastatic PC between February 2006 and September 2011 were selected for this retrospective study. FNA biopsy for pancreatic tumors had been performed percutaneously under extracorporeal ultrasound guidance until October 2009; then, beginning in November 2009, EUS-FNA has been performed. We reviewed the complete medical records of all patients who met the selection criteria for the following data: sex, age, location and size of the targeted tumor, histological and/or cytological findings, details of puncture procedures, time from day of puncture until day of definitive diagnosis, and details of severe adverse events. RESULTS: Of the 121 patients who met the selection criteria, 46 had a percutaneous biopsy (Group A) and 75 had an EUS-FNA biopsy (Group B). Adequate cytological specimens were obtained in 42 Group A patients (91.3%) and all 75 Group B patients (P=0.0192), and histological specimens were obtained in 41 Group A patients (89.1%) and 65 Group B patients (86.7%). Diagnosis of malignancy by cytology was positive in 33 Group A patients (78.6%) and 72 Group B patients (94.6%) (P=0.0079). Malignancy by both cytology and pathology was found in 43 Group A (93.5%) and 73 Group B (97.3%) patients. The mean period from the puncture until the cytological diagnosis in Group B was 1.7 d, which was significantly shorter than that in Group A (4.1 d) (P < 0.0001). Severe adverse events were experienced in two Group A patients (4.3%) and in one Group B patient (1.3%). CONCLUSION: EUS-FNA, as well as percutaneous needle aspiration, is an effective modality to obtain cytopathological confirmation in patients with advanced PC.

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 utility of endoscopic ultrasound-guided fineneedle aspiration biopsy for glomus tumor of the stomach

A 52-year-old man was referred for further investigation of a gastric submucosal tumor on the greater curvature of the antrum. Endoscopic ultrasonography demonstrated a hypoechoic solid mass, which was primarily connected to the muscular layer of the stomach. We performed endoscopic ultrasoundguided fine-needle aspiration biopsy. The pathological examination showed proliferation of oval-shaped cells with nest formation, which stained strongly positive for muscle actin, and negative for c-kit, CD34, CD56,desmin, S-100, chromogranin, and neuron-specific enolase. Therefore, we performed laparoscopy and endoscopy cooperative surgery based on the preoperative diagnosis of glomus tumor of the stomach. The final histological diagnosis confirmed the preoperative diagnosis. Although preoperative diagnosis of glomus tumor of the stomach is difficult with conventional images and endoscopic biopsy, endoscopic ultrasoundguided fine-needle aspiration biopsy is an essential tool to gain histological evidence of glomus tumor of the stomach for early diagnosis.

The efficacy of rapid on-site evaluation during endoscopic ultrasound-guided fine needle aspiration of pancreatic masses

Background:Endoscopic ultrasound(EUS)-guided fine needle aspiration(FNA)has become the preferred method to diagnose pancreatic masses due to its minimally invasive approach and diagnostic accuracy.Many studies have shown that rapid on-site evaluation(ROSE)improves diagnostic yield by 10–30%;however,more recent studies have demonstrated effective diagnostic accuracy rates without ROSE.Our study aims to examine whether the current standard of performing ROSE after each FNA pass adds diagnostic value during EUS-guided FNA of pancreatic masses.Methods:We conducted a retrospective case series on patients who underwent EUS-guided FNA of pancreatic masses between February 2011 and October 2014.All cases were performed by one of three endoscopists at Emory University Hospital.Patient demographics,radiologic details of pancreatic masses and pathology reports of the biopsied pancreatic masses were examined.Results:A total of 184 procedures performed in 171 patients were reviewed.The final pathology reports of the biopsied pancreatic masses showed 128(70%)with confirmed malignancy.Only 64(50%)of these 128 cases initially showed malignant cells during ROSE.Among these 64 cases,23%required 5 or more FNA passes to first detect malignant cells.Conclusions:The use of ROSE during EUS-guided FNA of pancreatic masses may increase the diagnostic yield,since malignant cells were often detected during later FNA passes that would otherwise be missed if tissue sampling stopped prematurely.In addition,sample preparation for ROSE may be suboptimal,since malignant cells were only detected in 50%of cases.

Endoscopic ultrasound-guided fine-needle aspiration cytology in pancreaticobiliary carcinomas:diagnostic efficacy of cell-block immunocyto-chemistry

BACKGROUND： Endoscopic ultrasound-guided fine-needle aspiration cytology was demonstrated to be a useful tool for the diagnosis and staging of pancreaticobiliary neoplastic le- sions. Nonetheless, the diagnostic value of this procedure may be limited by low cellularity of the specimen, contamination of intestinal cells and unfeasibility of ancillary immunocy- tochemical procedures. The present study was to evaluate its usefulness in the diagnosis of neoplastic lesions.

Endoscopic ultrasound-guided fine-needle aspiration for suspected malignancies adjacent to the gastrointestinal tract

AIM: To investigate the impact of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in association with a multidisciplinary team evaluation for the detection of gastrointestinal malignancies.

Endoscopic ultrasound-guided fine-needle aspiration biopsy-Recent topics and technical tips

Endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNA) is a useful procedure that enables reliable pathological diagnoses of pancreatobiliary diseases, subepithelial lesions, and swollen lymph nodes. In recent years, a pathological diagnosis based on EUS-FNA has made it possible to provide accurate treatment methods not only in these fields, but also in respiratory organs and otorhinolaryngology. This review discusses the latest topics pertaining to EUS-FNA as well as procedural tips.

Endoscopic ultrasound guided fine needle aspiration and useful ancillary methods

The role of endoscopic ultrasound(EUS) in evaluating pancreatic pathology has been well documented from the beginning of its clinical use. High spatial resolution and the close proximity to the evaluated organs within the mediastinum and abdominal cavity allow detection of small focal lesions and precise tissue acquisition from suspected lesions within the reach of this method. Fine needle aspiration(FNA) is considered of additional value to EUS and is performed to obtain tissue diagnosis. Tissue acquisition from suspected lesions for cytological or histological analysis allows, not only the differentiation between malignant and non-malignant lesions, but, in most cases, also the accurate distinction between the various types of malignant lesions. It is well documented that the best results are achieved only if an adequate sample is obtained for further analysis, if the material is processed in an appropriate way, and if adequate ancillary methods are performed. This is a multi-step process and could be quite a challenge in some cases. In this article, we discuss the technical aspects of tissue acquisition by EUS-guided-FNA(EUS-FNA), as well as the role of an on-site cytopathologist, various means of specimen processing, and the selection of the appropriate ancillary method for providing an accurate tissue diagnosis and maximizing the yield of this method. The main goal of this review is to alert endosonographers, not only to the different possibilities of tissue acquisition, namely EUS-FNA, but also to bring to their attention the importance of proper sample processing in the evaluation of various lesions in the gastrointestinal tract and other accessible organs. All aspects of tissue acquisition(needles, suction, use of stylet, complications, etc.) have been well discussed lately. Adequate tissue samples enable comprehensive diagnoses, which answer the main clinical questions, thus enabling targeted therapy.