endoscopic ultrasonography-guided biliary drainage:Who,when,which,and how?

Both endoscopic ultrasonography(EUS)-guided choledochoduodenostomy( EUS- CDS) and EUS-guided hepaticogastrostomy(EUS-HGS) are relatively well established as alternatives to percutaneous transhepatic biliary drainage(PTBD). Both EUSCDS and EUS-HGS have high technical and clinical success rates(more than 90%) in high-volume centers. Complications for both procedures remain high at 10%-30%. Procedures performed by endoscopists who have done fewer than 20 cases sometimes result in severe or fatal complications. When learning EUSguided biliary drainage(EUS-BD), we recommend a mentor's supervision during at least the first 20 cases. For inoperable malignant lower biliary obstruction, a skillful endoscopist should perform EUS-BD before EUS-guided rendezvous technique(EUS-RV) and PTBD. We should be select EUS-BD for patients having altered anatomy from malignant tumors before balloon-enteroscope-assisted endoscopic retrograde cholangiopancreatography, EUS-RV, and PTBD. If both EUS-CDS and EUS-HGS are available, we should select EUS-CDS, according to published data. EUSBD will potentially become a first-line biliary drainage procedure in the near future.

Endoscopic ultrasonography-guided endoscopic treatment of pancreatic pseudocysts and walled-off necrosis:New technical developments

In the last decades,the treatment of pancreatic pseudocysts and necrosis occurring in the clinical context of acute and chronic pancreatitis has shifted towards minimally invasive endoscopic interventions.Surgical procedures can be avoided in many cases by using endoscopically placed,Endoscopic ultrasonography-guided techniques and drainages.Endoscopic ultrasound enables the placement of transmural plastic and metal stents or nasocystic tubes for the drainage of peripancreatic fluid collections.The development of selfexpanding metal stents and exchange free delivering systems have simplified the drainage of pancreatic fluid collections.This review will discuss available therapeutic techniques and new developments.

Histological diagnosis of gastric submucosal tumors: A pilot study of endoscopic ultrasonography-guided fine-needle aspiration biopsy vs mucosal cutting biopsy

AIM: To compare the usefulness of endoscopic ultrasonography-guided fine-needle aspiration biopsy(EUS-FNAB) without cytology and mucosal cutting biopsy(MCB) in the histological diagnosis of gastric submucosal tumor(SMT).METHODS: We prospectively compared the diagnostic yield, feasibility, and safety of EUS-FNAB and those of MCB based on endoscopic submucosal dissection. The cases of 20 consecutive patients with gastric SMT ≥1 cm in diameter. who underwent both EUS-FNAB and MCB were investigated.RESULTS: The histological diagnoses were gastrointestinal stromal tumors(n = 7), leiomyoma(n =6), schwannoma(n = 2), aberrant pancreas(n = 2), and one case each of glomus tumor, metastatic hepatocellular carcinoma, and no-diagnosis. The tumors' mean size was 23.6 mm. Histological diagnosis was made in 65.0% of the EUS-FNABs and 60.0% of the MCBs, a nonsignificant difference. There were no significant differences in the diagnostic yield concerning the tumor location or tumor size between the two methods. However, diagnostic specimens were significantly more frequently obtained in lesions with intraluminal growth than in those with extraluminal growth by the MCB method(P = 0.01). All four SMTs with extraluminal growth were diagnosed only by EUSFNAB(P = 0.03). No complications were found in either method.CONCLUSION: MCB may be chosen as an alternative diagnostic modality in tumors showing the intraluminal growth pattern regardless of tumor size, whereas EUSFNAB should be performed for SMTs with extraluminal growth.

Resected tumor seeding in stomach wall due to endoscopic ultrasonography-guided fine needle aspiration of pancreatic adenocarcinoma

Endoscopic ultrasonography-guided fine needle aspiration(EUS-FNA) is a useful and relatively safe tool for the diagnosis and staging of pancreatic cancer. However, there have recently been several reports of tumor seeding after EUS-FNA of adenocarcinomas. A 78-year-old man was admitted to our hospital due to upper gastric pain. Examinations revealed a 20 mm mass in the pancreatic body, for which EUS-FNA was performed. The cytology of the lesion was adenocarcinoma, and the stage of the cancer was T3N0M0. The patient underwent surgery with curative intent, followed by adjuvant chemotherapy with S-1. An enlarging gastric submucosal tumor was found on gastroscopy at 28 mo after surgery accompanied by a rising level of CA19-9. Biopsy result was adenocarcinoma, consistent with a pancreatic primary tumor. Tumor seeding after EUS-FNA was strongly suspected. The patient underwent surgical resection of the gastric tumor with curative intent. The pathological result of the resected gastric specimen was adenocarcinoma with a perfectly matched mucin special stain result with the previously resected pancreatic cancer. This is the first case report of tumor seeding after EUS-FNA which was surgically resected and inspected pathologically.

Electrocautery vs non-electrocautery dilation catheters in endoscopic ultrasonography-guided pancreatic fluid collection drainage

AIM: To investigate the safety and utility of an electrocautery dilation catheter for endoscopic ultrasonography(EUS)-guided pancreatic fluid collection drainage.METHODS: A single-center, exploratory, retrospective study was conducted between August 2010 and August 2014. This study was approved by the Medical Ethics Committee of our institution. Informed, written consent was obtained from each patient prior to the procedure. The subjects included 28 consecutive patients who underwent EUS-guided transmural drainage(EUS-TD) for symptomatic pancreatic and peripancreatic fluid collections(PFCs) by fine needle aspiration using a 19-gauge needle. These patients were retrospectively divided into two groups based on the use of an electrocautery dilation catheter as a fistula dilation device; 15 patients were treated with an electrocautery dilation catheter(electrocautery group), and 13 patients were treated with a non-electrocautery dilation catheter(non-electrocautery group). We evaluated the technical and clinical successes and the adverse events associated with EUS-TD for the treatment of PFCs between the two groups.RESULTS: There were no significant differences in age, sex, type, location and diameter of PFCs between the groups. Thirteen patients(87%) in the electrocauterygroup and 10 patients(77%) in the non-electrocautery group presented with infected PFCs. The technical success rates of EUS-TD for the treatment of PFCs were 100%(15/15) and 100%(13/13) for the electrocautery and the non-electrocautery groups, respectively. The clinical success rates of EUS-TD for the treatment of PFCs were 67%(10/15) and 69%(9/13) for the electrocautery and the non-electrocautery groups, respectively(P = 0.794). The procedure time of EUS-TD for the treatment of PFCs in the electrocautery group was significantly shorter than that of the non-electrocautery group(mean ± SD: 30 ± 12 min vs 52 ± 20 min, P < 0.001). Adverse events associated with EUS-TD for the treatment of PFCs occurred in 0 patients and 1 patient for the electrocautery and the non-electrocautery groups, respectively(P = 0.942).CONCLUSION: EUS-TD using an electrocautery dilation catheter as a fistula dilation device for the treatment of symptomatic PFCs appears safe and contributes to a shorter procedure time.

Present state of endoscopic ultrasonography-guided fine needle aspiration for the diagnosis of autoimmune pancreatitis type 1

Autoimmune pancreatitis(AIP)is defined as pancreatitis caused by irregular narrowing of the pancreatic duct accompanied by pancreatic swelling,fibrosis and lymphocyte infiltration,events that are related to autoimmune mechanisms.The 2010 International Consensus Diagnostic Criteria for AIP defined pancreatitis as“type 1”when increased levels of serum IgG4 were present and other organs were involved;lymphoplasmacytic sclerosing pancreatitis was the main histological characteristic.Apart from surgery,endoscopic ultrasonographyguided fine needle aspiration(EUS-FNA)is the only method for the histological diagnosis of AIP;however,this method is difficult.The use of larger-diameter FNA needles and trucut biopsy did not improve the diagnostic performance of EUS-FNA,but it has improved gradually.In this review,we look back at past efforts to improve the diagnostic performance of EUS-FNA and reveal the present state of EUS-FNA for the histological diagnosis of AIP type 1.

Current clinical management of gastrointestinal stromal tumor

Gastrointestinal stromal tumors(GISTs) are the most common malignant subepithelial lesions(SELs) of the gastrointestinal tract. They originate from the interstitial cells of Cajal located within the muscle layer and are characterized by over-expression of the tyrosine kinase receptor KIT. Pathologically, diagnosis of a GIST relies on morphology and immunohistochemistry [KIT and/or discovered on gastrointestinal stromal tumor 1(DOG1) is generally positive]. The prognosis of this disease is associated with the tumor size and mitotic index. The standard treatment of a GIST without metastasis is surgical resection. A GIST with metastasis is usually only treated by tyrosine kinase inhibitors without radical cure; thus, early diagnosis is the only way to improve its prognosis. However, a GIST is usually detected as a SEL during endoscopy, and many benign and malignant conditions may manifest as SELs. Conventional endoscopic biopsy is difficult for tumors without ulceration. Most SELs have therefore been managed without a histological diagnosis. However, a favorable prognosis of a GIST is associated with early histological diagnosis and R0 resection. Endoscopic ultrasonography(EUS) and EUS-guided fine needle aspiration(EUSFNA) are critical for an accurate diagnosis of SELs. EUSFNA is safe and effective in enabling an early histological diagnosis and adequate treatment. This review outlines the current evidence for the diagnosis and management of GISTs, with an emphasis on early management of small SELs.

Current status of endoscopic retrograde cholangiopancreatography in patients with surgically altered anatomy

Endoscopic retrograde cholangiopancreatography(ERCP)in patients with surgically altered anatomy must be performed by a highly experienced endoscopist.The challenges are accessing the afferent limb in different types of reconstruction,cannulating a papilla with a reverse orientation,and performing therapeutic interventions with uncommon endoscopic accessories.The development of endoscopic techniques has led to higher success rates in this group of patients.Device-assisted ERCP is the endoscopic procedure of choice for high success rates in short-limb reconstruction;however,these success rate is lower in long-limb reconstruction.ERCP assisted by endoscopic ultrasonography is now popular because it can be performed independent of the limb length;however,it must be performed by a highly experienced and skilled endoscopist.Stent deployment and small stone removal can be performed immediately after ERCP assisted by endoscopic ultrasonography,but the second session is needed for other difficult procedures such as cholangioscopy-guided electrohydraulic lithotripsy.Laparoscopic-assisted ERCP has an almost 100%success rate in longlimb reconstruction because of the use of a conventional side-view duodenoscope,which is compatible with standard accessories.This requires cooperation between the surgeon and endoscopist and is suitable in urgent situations requiring concomitant cholecystectomy.This review focuses on the advantages,disadvantages,and outcomes of various procedures that are suitable in different situations and reconstruction types.Emerging new techniques and their outcomes are also discussed.

Ten-year survival of hepatocellular carcinoma patients undergoing radiofrequency ablation as a first-line treatment

AIM: To investigate the long-term survival and prognostic factors in hepatocellular carcinoma (HCC) patients undergoing radiofrequency ablation (RFA) as a first-line treatment.METHODS: From 2000 to 2013, 316 consecutive patients with 404 HCC (1.0-5.0 cm; mean: 3.2 &#x000b1; 1.1 cm) underwent ultrasonography-guided percutaneous RFA as a first-line treatment. There were 250 males and 66 females with an average age of 60.1 &#x000b1; 10.8 years (24-87 years). Patients were followed for 1 year to &#x0003e; 10 years after RFA (234, 181, 136, and 71 for 3, 5, 7, and 10 years, respectively). Overall local response rates and long-term survival rates were assessed. Survival results were generated using Kaplan-Meier estimates, and multivariate analysis was performed using the Cox regression model.RESULTS: In total, 548 RFA sessions were performed and major complications occurred in 10 sessions (1.8%). Local tumor progression and/or new tumor development were observed in 43.3% (132/305) of the patients during the follow-up period. Overall 5- and 10-year survival rates were 49.7% and 28.4%, respectively. Based on multivariate analysis, three factors were identified as independent prognostic factors for overall survival: Child-Pugh classification (HR = 4.054, P &#x0003c; 0.001), portal vein hypertension (HR = 2.743, P = 0.002), and tumor number (HR = 2.693, P = 0.003). The local progression-free 5- and 10-year survival rates were 42.7% and 19.5%. In addition to the Child-Pugh classification and the number of tumors, the number of RFA sessions (HR = 1.550, P = 0.002) was associated with local progression-free survival.CONCLUSION: RFA can achieve acceptable outcomes for HCC patients as a first-line treatment, especially for patients with Child-Pugh class A, patients with a single tumor and patients without portal vein hypertension.

Endoscopic ultrasonography guided-fine needle aspirationfor the diagnosis of solid pancreaticobiliary lesions:Clinicalaspects to improve the diagnosis

Endoscopic ultrasonography-guided fine-needle aspiration(EUS-FNA) has been applied to pancreaticobiliary lesions since the 1990 s and is in widespread use throughout the world today. We used this method to confirm the pathological evidence of the pancreaticobiliary lesions and to perform suitable therapies. Complications of EUS-FNA are quite rare, but some of them are severe. Operators should master conventional EUS observation and experience a minimum of 20-30 cases of supervised EUS-FNA on non-pancreatic and pancreatic lesions before attempting solo EUSFNA. Studies conducted on pancreaticobiliary EUSFNA have focused on selection of suitable instruments(e.g., needle selection) and sampling techniques(e.g., fanning method, suction level, with or without a stylet, optimum number of passes). Today, the diagnostic ability of EUS-FNA is still improving; the detection of pancreatic cancer(PC) currently has a sensitivity of 90%-95% and specificity of 95%-100%. In addition to PC, a variety of rare pancreatic tumors can be discriminated by conducting immunohistochemistry on the FNA materials. A flexible, large caliber needle has been used to obtain a large piece of tissue, which can provide sufficient histological information to be helpful in classifying benign pancreatic lesions. EUSFNA can supply high diagnostic yields even for biliary lesions or peri-pancreaticobiliary lymph nodes. This review focuses on the clinical aspects of EUS-FNA in the pancreaticobiliary field, with the aim of providing information that can enable more accurate and efficient diagnosis.

Lumen-apposing metal stents for malignant biliary obstruction: Is this the ultimate horizon of our experience?

In the last years, endoscopic ultrasonography (EUS) has evolved from a purely diagnostic technique to a more and more complex interventional procedure, with the possibility to perform several type of therapeutic interventions. Among these, EUS-guided biliary drainage (BD) is gaining popularity as a therapeutic approach after failed endoscopic retrograde cholangiopancreatography in distal malignant biliary obstruction (MBO), due to the avoidance of external drainage, a lower rate of adverse events and re-interventions, and lower costs compared to percutaneous trans-hepatic BD. Initially, devices created for luminal procedures (e.g., luminal biliary stents) have been adapted to the new trans-luminal EUSguided interventions, with predictable shortcomings in technical success, outcome and adverse events. More recently, new metal stents specifically designed for transluminal drainage, namely lumen-apposing metal stents (LAMS), have been made available for EUS-guided procedures. An electrocautery enhanced delivery system (EC-LAMS), which allows direct access of the delivery system to the target lumen, has subsequently simplified the classic multi-step procedure of EUS-guided drainages. EUS-BD using LAMS and ECLAMS has been demonstrated effective and safe, and currently seems one of the most performing techniques for EUS-BD. In this Review, we summarize the evolution of the EUS-BD in distal MBO, focusing on the novelty of LAMS and analyzing the unresolved questions about the possible role of EUS as the first therapeutic option to achieve BD in this setting of patients.

Endoscopic ultrasound-guided choledochoduodenostomy in patients with failed endoscopic retrograde cholangiopancreatography

Endoscopic ultrasonography （EUS）-guided biliary drainage was performed for treatment of patients who have obstructive jaundice in cases of failed endoscopic retrograde cholangiopancreatography （ERCP）. In the present study, we introduced the feasibility and outcome of EUS-guided choledochoduodenostomy in four patients who failed in ERCR We performed the procedure in 2 papilla of Vater, including one resectable case, and 2 cases of cancer of the head of pancreas. Using a curved linear array echoendoscope, a 19 G needle or a needle knife was punctured transduodenally into the bile duct under EUS visualization. Using a biliary catheter for dilation, or papillary balloon dilator, a 7-Fr plastic stent was inserted through the choledochoduodenostomy site into the extrahepatic bile duct. In 3 （75%） of 4 cases, an indwelling plastic stent was placed, and in one case in which the stent could not be advanced into the bile duct, a naso-biliary drainage tube was placed instead. In all cases, the obstructive jaundice rapidly improved after the procedure. Focal peritonitis and bleeding not requiring blood transfusion was seen in one case. In this case, pancreatoduodenectomy was performed and the surgical findings revealed severe adhesion around the choledochoduodenostomy site. Although further studies and development of devices are mandatory, EUS-guided choledochoduodenostomy appears to be an effective alternative to ERCP in selected cases.

Comprehensive review on EUS-guided biliary drainage

Feasibility of endoscopic retrograde cholangiopancreatography(ERCP) for biliary drainage is not always applicable due to anatomical alterations or to inability to access the papilla. Percutaneous transhepatic biliary drainage has always been considered the only alternative for this indication. However,endoscopic ultrasonography-guided biliary drainage represents a valid option to replace percutaneous transhepatic biliary drainage when ERCP fails. According to the access site to the biliary tree,two kinds of approaches may be described: the intrahepatic and the extrahepatic. Endoscopic ultrasonography-guided rendezvous transpapillary drainage is performed where the second portion of the duodenum is easily reached but conventional ERCP fails. The recent introduction of self-expandable metal stents and lumen-apposing metal stents has improved this field. However,the role of the latter is still controversial. Echoendoscopic transmural biliary drainage can be challenging with potential severe adverse events. Therefore,trained endoscopists,in both ERCP and endoscopic ultrasonography are needed with surgical and radiological backup.

Clinical implications of doubling time of gastrointestinal submucosal tumors

AIM To evaluate the efficacy of doubling time(DT) of gastrointestinal submucosal tumors(GIST).METHODS From April 1987 through November 2012, a total of 323 patients were given a final histopathological diagnosis of GISTs on surgical resection or endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA) in Kitasato University East Hospital or Kitasato University Hospital. We studied 53 of these patients(34 with resected tumors and 19 with unresected tumors) whose tumors could be measured on EUS on at least two successive occasions. The histopathological diagnosis was GIST in 34 patients, leiomyoma in 5, schwannoma in 3, ectopic pancreas in 1, hamartoma in 1, cyst in 1, Brunner's adenoma in 1, and spindle-cell tumor in 7. We retrospectively calculated the DT of GISTs on the basis of the time course of EUS findings to estimate the growth rate of such tumors.RESULTS The DT was 17.2 mo for GIST, as compared with 231.2 mo for leiomyoma, 104.7 mo for schwannoma, 274.9mo for ectopic pancreas, 61.2 mo for hamartoma, 49.0 mo for cyst, and 134.7 mo for Brunner's adenoma. The GISTs were divided into risk classes on the basis of tumor diameters and mitotic figures(Fletcher's classification). The classification was extremely low risk or low risk in 28 patients, intermediate risk in 3, and high risk in 3. DT of GIST according to risk was 24.0 mo for extremely low-risk plus low-risk GIST, 17.1 mo for intermediate-risk GIST, and 3.9 mo for high-risk GIST. DT of GIST was significantly shorter than that of leiomyoma plus schwannoma(P < 0.05), and DT of high-risk GIST was significantly shorter than that of extremely low-risk plus low-risk GIST(P < 0.05).CONCLUSION For GIST, a higher risk grade was associated with a significantly shorter DT. Small SMTs should initially be followed up within 6 mo after detection.

Cystic pancreatic lesions,the endless dilemma

Cystic pancreatic lesions involve a wide variety of pathological entities that include neoplastic and non-neoplastic lesions.The proper diagnosis,differentiation,and staging of these cystic lesions are considered a crucial issue in planning further management.There are great challenges for their diagnostic models.In our time,new emerging methods for this diagnosis have been discovered.Endoscopic ultrasonography-guided fine-needle aspiration cytology with chemical and molecular analysis of cyst fluid and EUS-guided fine needlebased confocal laser endomicroscopy,through the needle microforceps biopsy,and single-operator cho-langioscopy/pancreatoscopy are promising methods that have been used in the diagnosis of cystic pancreatic lesions.Hereby we discuss the diagnosis of cystic pancreatic lesions and the benefits of various diagnostic models.

Modified single transluminal gateway transcystic multiple drainage technique for a huge infected walled-off pancreatic necrosis: A case report

We report a successful endoscopic ultrasonographyguided drainage of a huge infected multilocular walledoff necrosis(WON) that was treated by a modified single transluminal gateway transcystic multiple drainage(SGTMD) technique. After placing a widecaliber fully covered metal stent, follow-up computed tomography revealed an undrained subcavity of WON. A large fistula that was created by the wide-caliber metal stent enabled the insertion of a forward-viewing upper endoscope directly into the main cavity, and the narrow connection route within the main cavity to the subcavity was identified with a direct view, leading to the successful drainage of the subcavity. This modified SGTMD technique appears to be useful for seeking connection routes between subcavities of WON in some cases.

Interventional endoscopic ultrasonography for pancreatic cancer

Endoscopic ultrasonography(EUS)represents the combination of endoscopy and intraluminal ultrasonography.This allows use of a high-frequency transducer(5-20 MHz)that,due to the short distance to the target lesion,provides ultrasonographic images of higher resolution than those obtained from other imaging modalities,including multiple-detector-row-computed tomography,magnetic resonance imaging,and positron emission tomography.EUS is now a widely accepted modality for diagnosing pancreatic diseases.However,the most important limitation of EUS has been the lack of specificity in differentiating between benign and malignant changes.In 1992,EUS-guided fine needle aspiration(FNA)of lesions in the pancreas head was introduced into clinical practice,using a curved linear-array echoendoscope.Since then,EUS has evolved from EUS imaging to EUSFNA and wider applications.Interventional EUS for pancreatic cancer includes EUS-FNA,EUS-guided fine needle injection,EUS-guided biliary drainage and anastomosis,EUS-guided celiac neurolysis,radiofrequency ablation,brachytherapy,and delivery of a growing number of anti-tumor agents.This review focuses on interventional EUS,including EUS-FNA and therapeutic EUS for pancreatic cancer.

Comparison of smear cytology with liquid-based cytology in pancreatic lesions: A systematic review and meta-analysis

BACKGROUND Endoscopic ultrasonography-guided fine-needle aspiration(EUS-FNA)is a safe and accurate technique to confirm the diagnosis of pancreatic cancers.Recently,numerous studies comparing the diagnostic efficacy of smear cytology(SC)and liquid-based cytology(LBC)for pancreatic lesions yielded mixed results.AIM To compare and identify the better cytology method for EUS-FNA in pancreatic lesions.METHODS A comprehensive search of PubMed,Embase,and Cochrane was undertaken through July 18,2020.The primary endpoint was diagnostic accuracy(sensitivity and specificity).Secondary outcomes included sample adequacy and post procedure complications.In addition,factors affecting diagnostic efficacy were discussed.RESULTS Data on a total of 1121 comparisons from 10 studies met the inclusion criteria.Pooled rates of sensitivity for SC and LBC were 78%(67%-87%)vs 75%(67%-81%),respectively.In any case,both SC and LBC exhibited a high specificity close to 100%.Inadequate samples more often appeared in LBC compared with SC.However,the LBC samples exhibited a better visual field than SC.Very few post procedure complications were observed.CONCLUSION Our data suggested that for EUS-FNA in pancreatic lesions(particularly solid lesions),SC with Rapid On-Site Evaluation represents a superior diagnostic technique.If Rapid On-Site Evaluation is unavailable,LBC may replace smears.The diagnostic accuracy of LBC depends on different LBC techniques.

Accuracy of endoscopic ultrasound-guided needle aspiration specimens for molecular diagnosis of non-small-cell lung carcinoma

BACKGROUND Endoscopic ultrasonography-guided fine-needle aspiration(EUS-FNA)and endobronchial ultrasound-guided transbronchial needle aspiration(EBUS-TBNA)are highly sensitive for diagnosing and staging lung cancer.In recent years,targeted therapy has shown great significance in the treatment of non-small cell lung carcinoma(NSCLC).Using these minimally invasive techniques to obtain specimens for molecular testing will provide patients with a more convenient diagnostic approach.AIM To evaluate the feasibility and accuracy of tissue samples obtained using EUSFNA and EBUS-TBNA for molecular diagnosis of NSCLC.METHODS A total of 83 patients with NSCLC underwent molecular testing using tissues obtained from EUS-FNA or EBUS-TBNA at the Tianjin Medical University Cancer Hospital from January 2017 to June 2019.All enrolled patients underwent chest computed tomography or positron emission tomography/computed tomography prior to puncture.We detected abnormal expression of EGFR,KRAS,MET,HER2,ROS1 and anaplastic lymphoma kinase protein.Two patients failed to complete molecular testing due to insufficient tumor tissue.The clinical features,puncture records,molecular testing results and targeted treatment in the remaining 81 patients were summarized.RESULTS In a total of 99 tissue samples obtained from 83 patients,molecular testing was successfully completed in 93 samples with a sample adequacy ratio of 93.9%(93/99).Biopsy samples from two patients failed to provide test results due to insufficient tumor tissue.In the remaining 81 patients,62 cases(76.5%)were found to have adenocarcinoma,11 cases(13.6%)had squamous cell carcinoma,3 cases(3.7%)had adenosquamous carcinoma and 5 cases(6.2%)had NSCLC-not otherwise specified.The results of molecular testing showed EGFR mutations in 21 cases(25.9%),KRAS mutations in 9 cases(11.1%),ROS-1 rearrangement in 1 case(1.2%)and anaplastic lymphoma kinase-positive in 5 cases(6.2%).Twentyfour patients with positive results received targeted therapy.The total effectiveness rate of targeted therapy was 66.7%(16/24),and the disease control rate was 83.3%(20/24).CONCLUSION Tissue samples obtained by EUS-FNA or EBUS-TBNA are feasible for the molecular diagnosis of NSCLC and can provide reliable evidence for clinical diagnosis and treatment.

Nonfunctional pancreatic neuroendocrine tumours misdiagnosed as autoimmune pancreatitis:A case report and review of literature

BACKGROUND Nonfunctional pancreatic neuroendocrine tumours are difficult to diagnose in the early stage of disease due to a lack of clinical symptoms,but they can rarely manifest as autoimmune pancreatitis.Autoimmune pancreatitis is an uncommon disease that may cause recurrent acute pancreatitis and is therefore often regarded as a special type of chronic pancreatitis.CASE SUMMARY We report a case of a 42-year-old female who had nonspecific upper abdominal pain for 4 years and radiological abnormalities of the pancreas that mimicked autoimmune pancreatitis.The symptoms and pancreatic imaging did not improve following 1 year of steroid therapy.Finally,pancreatic biopsy was performed through endoscopic ultrasonography-guided fine-needle aspiration biopsy,and nonfunctional pancreatic neuroendocrine tumours were ultimately diagnosed.Pancreatectomy has resolved her symptoms.CONCLUSION Therefore,the differentiation of nonfunctional pancreatic neuroendocrine tumours from autoimmune pancreatitis is very important,although it is rare.We propose that endoscopic ultrasonography-guided fine-needle aspiration biopsy should be performed if imaging characteristics are equivocal or the diagnosis is in question.