EUS-guided fine needle aspiration of the liver: indications, yield, and safety based on an international survey of 167 cases

Endoscopic ultrasound-guided tissue acquisition for focal liver lesions in patients with a history of multiple primary malignant neoplasms

Objective

This study aimed to investigate the usefulness of endoscopic ultrasound-guided tissue acquisition (EUS-TA) for diagnosing focal liver lesions in patients with a history of multiple primary malignant neoplasms.

Methods

Among patients who underwent EUS-TA for focal liver lesions between 2016 and 2022, those with a history of multiple malignant neoplasms were included. A histologically confirmed malignant tumor within the past 5 years before EUS-TA was defined as a history of malignant neoplasm. The primary outcomes were diagnostic ability and adverse events of EUS-TA.

Results

This study included 16 patients (median age, 73 [33-90] years), the median tumor size was 32 (6-51) mm, 14 had a history of double malignant neoplasms, whereas two had triple malignant neoplasms. Malignant neoplasms were detected histologically or cytologically in all cases. Immunohistochemistry was performed in 75% (12/16), and the final diagnosis of EUS-TA was metastatic liver tumor in 12 patients, and primary malignant liver tumor in four patients. The primary site could be identified in 11 of 12 metastatic tumor cases. The diagnostic yield of EUS-TA was 100% (16/16) for differentiating benign and malignant tumors and 94% (15/16) for confirming the histological type including the primary site of metastatic lesions. No adverse events were associated with the procedure.

Conclusion

EUS-TA is a useful diagnostic modality for focal liver lesions in patients with a history of multiple malignant neoplasms, allowing for the differential diagnosis of primary and metastatic tumors and identification of the primary site of metastatic lesions.

Endoscopic ultrasound-guided fine-needle aspiration in the diagnostic value of focal liver lesions: A systematic analysis of 88 cases (with video)

BACKGROUND AND AIMS

Endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) is an important diagnostic tool for suspected parenchymal lesions in the gastrointestinal tract and adjacent organs. Our study aimed to evaluate the safety and effectiveness of EUS-FNA in focal liver lesions (FLLs).

METHOD

Data from 88 patients diagnosed with FLLs by imaging who underwent EUS-FNA from 1 January 2017 to 31 August 2022 were reviewed in our retrospective study at the Second Affiliated Hospital of Soochow University and Ruijin Hospital of the School of Medicine of Shanghai Jiao Tong University. The EUS-FNA biopsy results were compared with the final diagnosis to evaluate diagnostic value. The relevant factors were analysed to determine their influence on EUS-FNA biopsy results.

RESULTS

The 88 patients analysed in this study resulted in a final diagnosis of 86 malignant and two benign cases. The overall diagnostic accuracy of EUS-FNA in FLLs was 93.18 % (82/88; 95 % Confidence Interval [CI], 87.9-98.5), with a sensitivity, specificity, positive predictive value, and negative predictive value of 93.02 % (80/86; 95 %CI, 87.6-98.4), 100 % (2/2; 95 %CI, 100-100), 100 % (80/80; 95 %CI, 100-100), and 25 % (2/8; 95 %CI, -5-55.0), respectively. The parameters related to lesion and procedure were not significantly different between these two groups (p > 0.05). The number of puncture needles in the groups showed a statistically significant difference between multiple and single punctures (p = 0.001).

CONCLUSION

Our data revealed that EUS-FNA is a safe and reliable diagnostic method for FLLs that shows high accuracy.

Endoscopic Ultrasound-Guided Fine Needle Biopsy of Focal Liver Lesions: An Effective Mini-Invasive Alternative to the Percutaneous Approach

Despite the introduction of serological neoplastic biomarkers and typical radiological characteristics in clinical practice, liver biopsy (LB) is often still necessary to establish a histological diagnosis, especially in ambiguous cases. Nowadays, LB via the percutaneous approach (PC-LB), under computed tomography (CT) scan or ultrasonography (US) guidance, is the route of choice. However, certain focal liver lesions can be challenging to access percutaneously. In such cases, endoscopic ultrasound (EUS)-guided fine needle biopsy (FNB) may represent an attractive, minimally invasive alternative. This retrospective observational study aimed to evaluate the efficacy, diagnostic performance, and safety of EUS-FNB conducted on 58 focal liver lesions located in both liver lobes. The adequacy of FNB samples for focal liver lesions located in the left and right lobes was 100% and 81.2%, respectively, and the difference was statistically significant (p = 0.001). Technical success was 100% for both liver lobes. The overall sensitivity and specificity were 95% and 100%, respectively. EUS-FNB is effective in making an accurate diagnosis with an excellent safety profile for focal liver lesions located in both liver lobes.

Endoscopic Ultrasound-Guided Tissue Sampling for the Cytohistological Diagnosis of Focal Liver Lesions

BACKGROUND

Focal liver lesions (FLL) often require cytohistological evaluation. Endoscopic Ultrasound (EUS)-guided tissue acquisition (EUS-TA) is highly accurate in diagnosing pancreatic and gastrointestinal malignancies. The aim of our study was to evaluate the role of EUS-TA in the characterization of FLL.

METHODS

A retrospective analysis of a prospective database of patients who underwent EUS-TA for the evaluation of FLL. Diagnostic yield, adverse events and factors associated with diagnostic yield were evaluated as endpoints. The effect of variables such as needle size, lesion size, rapid on-site evaluation (ROSE) and the use of cytological or histological needles were analyzed.

RESULTS

A total of 114 cases were included (mean age 68.05 ± 11.35 years, 64 male). A correct diagnosis was made using EUS-TA in 100 of the 114 cases (diagnostic yield of 88%). The EUS-TA of additional extrahepatic lesions during the same EUS procedure increased the diagnostic yield to 94%. No adverse events were reported. Multivariate analysis did not identify any factor influencing the diagnostic yield.

CONCLUSIONS

EUS-TA is a highly accurate and safe technique for the differential diagnosis of FLL and could be considered as the primary approach in this setting.

Endoscopic ultrasound-guided tissue acquisition for focal liver lesions in the caudate lobe: a report of seven cases

The caudate lobe of the liver is located deep within the body and surrounded by major blood vessels, such as inferior vena cava, portal vein, and hepatic veins. Thus, percutaneous biopsy is technically challenging. Herein, we report seven patients with focal liver lesions in the caudate lobe who underwent endoscopic ultrasound-guided tissue acquisition (EUS-TA). Their median age was 56 (25-79) years, consisting five males and two females, and the median lesion size was 44 (19-77) mm. Transgastric EUS-TA was performed in all patients. The needles used were 22G and 25G in six patients and one patient, and the median procedure time was 18 (13-30) min. In all patients, adequate specimens were collected, and pathological diagnosis was possible (three intrahepatic cholangiocarcinoma, two metastatic tumors from pancreatic cancer, one hepatocellular carcinoma, and one focal nodular hyperplasia). No adverse events associated with the procedure were observed. EUS-TA can be the first choice for tissue acquisition of the caudate lobe lesions.

Diagnostic and therapeutic role of endoscopic ultrasound in liver diseases: A systematic review and meta-analysis

BACKGROUND

In hepatology, the clinical use of endoscopic ultrasound (EUS) has experienced a notable increase in recent times. These applications range from the diagnosis to the treatment of various liver diseases. Therefore, this systematic review summarizes the evidence for the diagnostic and therapeutic roles of EUS in liver diseases.

AIM

To examine and summarize the current available evidence of the possible roles of the EUS in making a suitable diagnosis in liver diseases as well as the therapeutic accuracy and efficacy.

METHODS

PubMed, Medline, Cochrane Library, Web of Science, and Google Scholar databases were extensively searched until October 2023. The methodological quality of the eligible articles was assessed using the Newcastle-Ottawa scale or Cochrane Risk of Bias tool. In addition, statistical analyses were performed using the Comprehensive Meta-Analysis software.

RESULTS

Overall, 45 articles on EUS were included (28 on diagnostic role and 17 on therapeutic role). Pooled analysis demonstrated that EUS diagnostic tests had an accuracy of 92.4% for focal liver lesions (FLL) and 96.6% for parenchymal liver diseases. EUS-guided liver biopsies with either fine needle aspiration or fine needle biopsy had low complication rates when sampling FLL and parenchymal liver diseases (3.1% and 8.7%, respectively). Analysis of data from four studies showed that EUS-guided liver abscess had high clinical (90.7%) and technical success (90.7%) without significant complications. Similarly, EUS-guided interventions for the treatment of gastric varices (GV) have high technical success (98%) and GV obliteration rate (84%) with few complications (15%) and rebleeding events (17%).

CONCLUSION

EUS in liver diseases is a promising technique with the potential to be considered a first-line therapeutic and diagnostic option in selected cases.

New window into hepatitis B in Africa: Liver sampling combined with single cell omics enables deep and longitudinal assessment of intrahepatic immunity in Zambia

In Lusaka, Zambia, we introduced liver fine needle aspiration (FNA) into a research cohort of adults with treatment-naïve chronic hepatitis B virus (HBV) infection, with and without HIV coinfection, as well as with acute HBV infection. Over 117 enrollment and 47 longitudinal FNAs (at 1 year follow-up), we established participant acceptability and safety. We also demonstrated the quality of the material through single cell RNA sequencing of selected enrollment FNAs, which revealed a range of immune cells. This approach can drive new insights into HBV immunology, informing cure strategies, and can improve our understanding of HBV natural history in Africa.

Diagnostic value of imaging modalities in primary squamous cell carcinoma of the liver

Primary squamous cell carcinoma of the liver (PSCCL) is rare. PSCCL's lack of specific clinical manifestations and laboratory tests necessitate preoperative diagnosis via imaging examination. Conventional ultrasound (US) demonstrates a mass with mixed echogenicity, and contrast-enhanced US shows a circular pattern of "fast forward, fast backward or slow backward, high enhancement." Enhanced computed tomography (CT) showed enhancement in the center or edge of the lesion, and the density of the enhanced lesion was lower than that of the liver tissue in the same layer. Positron emission tomography-CT demonstrates an inhomogeneous low-density mass with increased 18F-FDG metabolism. Magnetic resonance imaging shows low signal intensity on T1-weighed images (T1WI) and high signal on T2-weighed images (T2WI). By summarizing the imaging characteristics of PSCCL, this review aims to improve clinicians' understanding of PSCCL and its diagnosis.

Curative surgery for primary squamous cell carcinoma of the liver: a rare case study

Primary squamous cell carcinoma (SCC) of the liver is an extremely rare disease with a very poor prognosis. An 83-year-old woman was referred to our hospital with left abdominal pain. Laboratory data showed mildly elevated C-reactive protein and biliary enzymes. The tumor markers carcinoembryonic antigen, alpha-fetoprotein, and carbohydrate antigen 19-9 were within normal ranges. Contrast-enhanced computed tomography revealed a 60 mm-sized low-density mass with poor contrast enhancement located in the lateral segment of the liver. The tumor showed low signal on T₁-weighted magnetic resonance imaging (MRI) and high signal on T₂-weighted MRI. The cytology of bile juice showed no malignant findings. Endoscopic ultrasound-guided fine-needle aspiration biopsy was performed, which was suggestive of primary hepatic SCC. Tumor markers cytokeratin 19 fragment (CYFRA) and SCC-related antigen were elevated, at 25.2 ng/mL and 14.7 ng/mL, respectively. Left lobectomy and hilar lymph node dissection were performed. One month after surgery, the tumor marker values showed a marked decrease of 1.8 ng/mL for CYFRA and 0.3 ng/dL for SCC-related antigen. The patient has been without recurrence for more than one and half year postoperatively. SCC-related antigen and CYFRA were markedly decreased after tumor resection in this case, which may suggest their utility as tumor markers for SCC of liver origin.

Adverse Event Fatalities Related to GI Endoscopy

BACKGROUND

Death after endoscopy is rare, under-reported, and has variable causes. This study aimed to evaluate the incidence and causes of fatal endoscopic adverse events (AEs) across two academic medical centers and to identify patient-, procedure-, and sedation-related risk factors.

METHODS

This is a retrospective cohort study of fatal adverse events causally related to endoscopy at Denver Health Medical Center and the University of Colorado Hospital from 2011 to 2020. Fatal AEs were retrieved from the physician-reported database. Electronic medical records were then reviewed to determine medical history, procedure details, subsequent treatments, and time and cause of death.

RESULTS

From January 2011 to January 2020, 146,010 GI endoscopy procedures were performed. Median patient age was 70 [51-78] and 57% were male. Thirty-one deaths were identified, 28 of which were attributed to endoscopy, yielding a procedure-related fatality rate of 0.018%. Procedures included 11 EGDs, one colonoscopy, two flexible sigmoidoscopies, six ERCPs, seven upper EUS, and one PEG-J tube placement. Specific causes of death included aspiration in four patients (14%); cardiac arrest or myocardial infarction in seven patients (25%); perforation in nine patients (32%); bleeding in four patients (14%); cholangitis or sepsis without perforation in three patients (11%); and acute pancreatitis in one patient (3.6%).

CONCLUSIONS

Fatal endoscopic AEs were rare but tended to occur in older patients with major comorbidities. Most deaths occurred from aspiration pneumonia, cardiac arrest, or perforation-related sepsis within 1 week of the procedure.

Role of endoscopic ultrasound-guided liver biopsy: a meta-analysis

BACKGROUND

Endoscopic ultrasound-guided liver biopsy (EUS-LB) is an evolving technique. In this meta-analysis, we aimed to evaluate the value of EUS-LB for parenchymal and focal liver lesions. Besides, we aimed to assess the influences of needle-related factors on the performance of EUS-LB. Additionally, we aimed to assess the influence of various criteria on specimen adequacy.

METHODS

We searched the PubMed, Embase, Cochrane Library databases up to 10 October 2021. The primary outcome was diagnostic yield, specimen adequacy, qualified specimens evaluated by rapid on-site evaluation (ROSE). The secondary outcome was adverse events. Subgroup analyses were based on needle type, needle size, fine-needle biopsy (FNB) needle type. A sensitivity analysis was conducted on specimen adequacy based on two definition criteria.

RESULTS

In total, 33 studies were included. Pooled rates of diagnostic yield, specimen adequacy, qualified specimen by ROSE, adverse events were 95%, 84%, 93%, 3%. Subgroup analyses showed that Acquire needles generated higher diagnostic yield than SharkCore needles (99% vs. 88%, p = .047). Additionally, FNB needles demonstrated a higher rate of adverse events than FNA needles (6% vs. 1%, p = .028). Sensitivity analysis on specimen adequacy based on various criteria demonstrated that the specimen adequacy rate defined by the AASLD criterion was lower than that of the commonly-used criterion (37% vs. 84%, p = .001).

CONCLUSION

EUS-LB is effective and safe for liver biopsy. Acquire needles provide better specimens than SharkCore needles. FNB needles may increase the risk of adverse events compared with FNA needles. The AASLD criterion is harder to achieve than the commonly-used criterion.

Role of endoscopic ultrasound in the field of hepatology: Recent advances and future trends

The role of endoscopic ultrasound (EUS) as a diagnostic and therapeutic modality for the management of various gastrointestinal diseases has been expanding. The imaging or intervention for various liver diseases has primarily been the domain of radiologists. With the advances in EUS, the domain of endosonologists is rapidly expanding in the field of hepatology. The ability to combine endoscopy and sonography in one hybrid device is a unique property of EUS, together with the ability to bring its probe/transducer near the liver, the area of interest. Its excellent spatial resolution and ability to provide real-time images coupled with several enhancement techniques, such as contrast-enhanced (CE) EUS, have facilitated the growth of EUS. The concept of “Endo-hepatology” encompasses the wide range of diagnostic and therapeutic procedures that are now gradually becoming feasible for managing various liver diseases. Diagnostic advancements can enable a wide array of techniques from elastography and liver biopsy for liver parenchymal diseases, to CE-EUS for focal liver lesions to portal pressure measurements for managing various liver conditions. Similarly, therapeutic advancements range from EUS-guided eradication of varices, drainage of bilomas and abscesses to various EUS-guided modalities of liver tumor management. We provide a comprehensive review of all the different diagnostic and therapeutic EUS modalities available for the management of various liver diseases. A synopsis of all the technical details involving each procedure and the available data has been tabulated, and the future trends in this area have been highlighted.

Role of Endoscopic Ultrasound in Liver Disease: Where Do We Stand?

As the burden of liver disease in the general populace steadily increases, so does the need for both advanced diagnostic and treatment options. Endoscopic ultrasound is a reliable diagnostic and therapeutic method that has an established role, foremost in pancreatobiliary pathology. This paper aims to summarize the growing role of endoscopic ultrasound in hepatology based on the search of the current literature. A number of applications of endoscopic ultrasound are reviewed, including both noninvasive methods and tissue acquisition in focal and diffuse liver disease, portal hypertension measurement, detection and management of gastric and esophageal varices, treatment of focal liver lesions and staging of pancreatobiliary malignancies, treatment of cystic and solid liver lesions, as well as liver abscess drainage. Both hepatologists and endoscopists should be aware of the evolving role of endoscopic ultrasound in liver disease. The inherent invasive nature of endoscopic examination limits its use to a targeted population identified using noninvasive methods. Endoscopic ultrasound is one the most versatile methods in gastroenterology, allowing immediate access with detection, sampling, and treatment of digestive tract pathology. Further expansion of its use in hepatology is immanent.

Role of EUS in detection of liver metastasis not seen by computed tomography or magnetic resonance imaging during staging of pancreatic, gastrointestinal, and thoracic malignancies

Background and Objectives:

Liver metastases might not be detected by computed tomography (CT) and magnetic resonance imaging (MRI) due to their small size, but they can be detected by EUS. Furthermore, EUS-FNA has a significant impact on improving the diagnostic accuracy of EUS. The purpose of this study was to assess the feasibility of EUS in detection of occult small hepatic focal lesions at the time of primary tumor staging, not seen by CT or MRI.

Methods:

This prospective study included 730 patients who underwent EUS for staging or sampling of gastrointestinal, pancreatic, or thoracic malignancy. The liver was examined thoroughly for detection of occult lesions. CT or MRI was done within 1 week of EUS examination.

Results:

EUS examination of the liver detected focal lesions in 150 patients (20.5%) and metastases in 118 patients (16.2%); meanwhile, CT and MRI detected focal lesions in 99 patients (13.6%) and metastases in 82 patients (11.2%). EUS missed focal lesions in 7 patients, 6 of which were liver metastases (1.0% and 0.8%, respectively), while CT and MRI missed focal lesions in 58 patients, 42 of which were metastases (7.9% and 5.8%, respectively), which were detected by EUS.

Conclusion:

Thorough dedicated EUS examination of the liver is a feasible useful tool for detection of small hepatic lesions missed by CT and MRI. It is not considered an extra financial burden to the patient or health-care system because those patients are indicated for EUS examination for evaluation of their original lesion in the first place. Furthermore, EUS-FNA can add another advantage in diagnosing the etiology of such lesions.

Hepatic Squamous Cell Carcinoma Diagnosed by Endoscopic Ultrasound-Guided Fine-Needle Aspiration

Primary hepatic squamous cell carcinoma (SCC) is a rare malignancy with aggressive clinical features. This is the first case report of a primary hepatic SCC diagnosed by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), which is a reliable and safe procedure for the histopathological diagnosis of liver lesions, even if the percutaneous approach is difficult due to ascites or hypervascularity at the puncture site. A 52-year-old man presented to the emergency department of a tertiary referral hospital with right upper quadrant abdominal pain and abdominal distention. Given the laboratory data, a diagnosis of spontaneous bacterial peritonitis (SBP) was made. Concurrently, an abdominal computed tomography (CT) scan revealed an 8 cm hypodense mass with delayed peripheral enhancement in the left hepatic lobe and paraaortic and perihepatic lymphadenopathy. As persistent ascites precluded percutaneous liver biopsy, we performed EUS-FNA of the liver mass, and the obtained specimen showed SCC. As otorhinolaryngological consultation and whole-body investigations, including chest CT, upper and lower endoscopy, and positron emission tomography CT, were all unremarkable except for the liver lesion and lymph nodes, a diagnosis of primary hepatic SCC with systemic lymph node metastasis was made. After treatment of SBP with antibiotics, we initiated chemotherapy concurrent with radiation therapy, adapted to his liver function. Radiation and three cycles of chemotherapy were not effective as the disease progressed, as seen on the follow-up CT scan, and the patient died of hepatic failure on the 134th day after diagnosis. In conclusion, EUS-FNA was a reliable method for tissue sampling in liver malignancies, particularly in selected patients with contraindications for percutaneous biopsy.

Personalized Approach to the Role of Endoscopic Ultrasound in the Diagnosis and Management of Pancreaticobiliary Malignancies

Pancreaticobiliary malignancies arise from different areas within the pancreas and biliary tree. Endoscopic ultrasound (EUS) is a well-recognized diagnostic and therapeutic modality in the treatment of pancreaticobiliary diseases, and more specifically, pancreaticobiliary malignancies. Traditionally used for diagnostic purposes, EUS plays a critical role in tissue sampling and cancer staging. The emergence of the new field of interventional EUS has allowed EUS to also play a critical role in therapeutic management. Novel interventional EUS procedures such as EUS-guided gastrojejunostomy (EUS-GE), EUS-guided biliary drainage (EUS-BD), and EUS-guided gallbladder drainage (EUS-GLB) can be utilized to treat complications of pancreaticobiliary malignancies such as gastric outlet obstruction, obstructive jaundice, and cholecystitis. In addition, interventional EUS procedures can be utilized for the palliation of unresectable malignancies both for source control with EUS-radiofrequency ablation (EUS-RFA) and for the treatment of abdominal pain refractory to opioid medications with EUS-guided celiac axis neurolysis. However, patient selection remains a critical component in both diagnostic and therapeutic interventions and must be tailored to individual patient wishes, disease pathology, and overall prognosis.

Improved detection of liver metastasis using Kupffer-phase imaging in contrast-enhanced harmonic EUS in patients with pancreatic cancer (with video)

BACKGROUND AND AIMS

Kupffer-phase imaging visualized by perfluorobutane (Sonazoid) distribution into normal liver tissues upon phagocytosis by Kupffer cells potentially aids in improving detection of liver metastasis compared with fundamental B-mode EUS (FB-EUS). However, the diagnostic performance of Kupffer-phase imaging in contrast-enhanced harmonic EUS (CH-EUS) remains unclear. Hence, this study aimed to evaluate the usefulness of CH-EUS-based Kupffer-phase imaging for diagnosing liver metastasis from pancreatic cancer.

METHODS

We retrospectively analyzed consecutive patients with pancreatic cancer who underwent contrast-enhanced CT (CE-CT) and FB-EUS, followed by CH-EUS, from 2011 to 2017. The diagnostic ability of CH-EUS against that of CE-CT and FB-EUS for metastasis in the left liver lobe was compared. Subsequently, the influences of CH-EUS on the determination of clinical stage and patient management for pancreatic cancer were assessed.

RESULTS

We enrolled 426 patients with pancreatic cancer. Metastasis in the left liver lobe was present in 27.2% of patients. The diagnostic accuracy of CE-CT, FB-EUS, and CH-EUS was 90.6%, 93.4%, and 98.4%, respectively. The sensitivity and diagnostic accuracy of CH-EUS for metastasis in the left liver lobe were significantly higher than those of FB-EUS or CE-CT. The sensitivity of CH-EUS for detecting small liver metastasis (<10 mm) was considerably higher than that of CE-CT or FB-EUS (P < .001). In 2.1% of patients, only CH-EUS could detect a single distant metastasis of the left liver lobe, thereby upgrading the tumor staging and altering the clinical management.

CONCLUSIONS

CH-EUS-based Kupffer-phase imaging increased the detectability of metastasis in the left liver lobe. This technique could be a reliable pretreatment imaging modality for clinical decision-making in patients with pancreatic cancer.

Comparative Study of an Ultrasound-guided Percutaneous Biopsy and Endoscopic Ultrasound-guided Fine-needle Aspiration for Liver Tumors

Objective Both a percutaneous biopsy and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) have been widely performed for liver tumors. However, no studies have compared these two biopsy methods. Method A retrospective study was conducted using medical records for patients who underwent a liver tumor biopsy from 2012 to 2019. The cases were classified into two groups for a comparison: an ultrasound-guided percutaneous biopsy group (percutaneous group) and an EUS-FNA group (EUS group). Results A total of 106 patients (47 in the percutaneous group and 59 in the EUS group) were included. The final diagnosis was malignant in 100 cases and benign in the remaining 6 cases. While the median lesion diameter was 62 mm in the percutaneous group, it was significantly smaller (34 mm) in the EUS group (p <0.01). The EUS group had more left lobe tumors than right lobe tumors. All cases of caudate lobe tumor (four cases) underwent EUS-FNA. The sensitivity, specificity, and accuracy of the procedure were 95%, 100%, and 96% in the percutaneous group and 100%, 100%, and 100% in the EUS group, respectively showing no significant difference. Adverse events were reported in 17% of the percutaneous group, which was significantly lower than in the EUS group (2%; p <0.01). Conclusion A percutaneous biopsy and EUS-FNA have equivalent diagnostic qualities for liver tumors, although EUS-FNA tends to be associated with fewer adverse events. A complete understanding of the characteristics of each procedure is essential when choosing the best biopsy method for each particular case.

Endoscopic ultrasound guided hepatic interventions

Intervention for liver disease has predominantly been performed through the percutaneous approach. However, as endoscopic ultrasound (EUS) applications have expanded, there have emerged various EUS-guided interventions for liver disease, a space we call "Endo-Hepatology". EUS-guided liver biopsy can be considered the "forerunner" of Endo-Hepatology and has become a clinical option for patients requiring histologic diagnosis and staging of their liver disease. EUS also enables direct access to the portal vein. Subsequently, many procedures are being explored, such as angiography, measurement of the portosystemic pressure gradient, portal vein sampling to detect cancer cell or DNA, and EUS-guided transhepatic intrahepatic portosystemic shunt creation. Since the transducer is close to the liver, especially the left and caudate lobes, EUS can be used as a rescue when the percutaneous approach is not favorable and EUS-guided treatments of liver tumor, cyst and abscess have been reported. This review summarizes the available studies of EUS-guided intervention in the liver.

Practical approach to linear EUS examination of the liver

EUS has become a substantial diagnostic and therapeutic modality for digestive tract conditions. The extent of endosonographic assessment is wide, and, among others, it allows for the evaluation of liver anatomy and related pathologies. Moreover, EUS assessment has proved more accurate in detecting small focal liver lesions missed by standard imaging examinations such as computed tomography or magnetic resonance. Endosonographically, various liver segments can be visualized by transgastric and transduodenal scanning following anatomical landmarks, thus providing arranged systematic examination. In addition, knowledge considering the correct position during examination is crucial for EUS-guided procedures such as hepaticogastrostomy, ablation of tumors, and measurement of portal pressure gradient. The evolution of EUS-guided intervention has contributed to the increasing importance of understanding the hepatic segmental anatomy during the EUS examination.

Endoscopic Ultrasound-Guided Fine Needle Aspiration Using a 22-G Needle for Hepatic Lesions: Single-Center Experience

BACKGROUND/AIMS

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has been accepted as a reliable tool in diagnosing and staging intra-abdominal tumors. In this study, we aimed to investigate the performance of EUS-FNA in the evaluation of liver masses and its impact on patient management and procedure-related complications retrospectively.

METHODS

Data of patients who underwent EUS-FNA biopsies due to liver masses between November 2017 and July 2018 were retrieved retrospectively. Biopsies were performed using 22-G needles. The demographics, EUS-FNA results, sensitivity and specificity of the procedure, negative predictive value, positive predictive value, and specimen sufficiency rates were assessed.

RESULTS

A total of 25 patients (10 females) were included in the study. The mean age was 62.73±15.2 years. The mean size of the masses was 34.50±16.04 mm. The technical success rate was 88%. During the EUS-FNA procedure, each patient had only one pass with 94.45% of aspirate sufficiency rate and 86.3% of biopsy sufficiency rate. The diagnostic accuracy rate was 86.3%. There were no complications.

CONCLUSION

For the evaluation of liver masses, EUS-FNA using a 22-G needle with even one pass had high aspiration and biopsy success rates accompanied with high diagnostic accuracy rates.

Complications of Endoscopic Ultrasound-Guided Fine Needle Aspiration: A Narrative Review

Considerable progress has been made recently in the use of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) to diagnose intra-luminal gastrointestinal lesions and extra-luminal lesions near the gastrointestinal tract. Numerous reports have indicated that EUS-FNA has high diagnostic performance and safety, which has led to the routine use of EUS-FNA and an increasing number of cases. Thus, while EUS-FNA has a low rate of complications, endoscopists may encounter these complications as the number of cases increases. Infrequent reports have also described life-threatening complications. Therefore, endoscopists should possess a comprehensive understanding of the complications of EUS-FNA, which include hemorrhage, perforation, infection, and acute pancreatitis, as well as their management. This review examines the available evidence regarding the complications associated with EUS-FNA, and the findings will be useful for ensuring that endoscopists perform EUS-FNA safely and appropriately.

Endoscopic ultrasound-guided parenchymal liver biopsy: a systematic review and meta-analysis

BACKGROUND

Endoscopic ultrasonography (EUS)-guided liver biopsy is a novel technique to obtain adequate liver samples for diagnosis of liver parenchymal diseases. There are studies that have evaluated the feasibility and safety of EUS-guided parenchymal liver biopsy (EUS-LB), however, factors that can influence specimen quality are yet to be determined. Our aim was to determine the diagnostic accuracy of EUS-LB and evaluate factors associated with specimen quality.

METHODS

We performed a detailed search of PubMed/MEDLINE and Web of Science™ databases to identify studies in which results of EUS-guided liver parenchymal biopsies were reported published up to July 2020. A random effects model was used to estimate pooled values (mean ± SE) for total specimen length (TSL) and complete portal tracts (CPT). Subgroup analyses were applied to find out the procedural factors associated with better specimen quality using Cochran's Q test. A total of 10 meta-analyses were done focusing on international studies. Total of 1326 patients who underwent EUS-LB. EUS-LBs performed for suspicion of parenchymal liver disease. Pooled mean values for TSL and CPT with subgroup analyses.

RESULTS

Twenty-three studies with a total of 1326 patients were included in our meta-analysis. Overall pooled mean TSL and CPT were 45.3 ± 4.6 mm and 15.8 ± 1.5, respectively. In subgroup analysis, core biopsy needles proved to better in terms of CPT than fine-needle aspiration needles (18.4 vs 10.99, p = 0.003). FNB with slow-pull or suction technique provided a similar TSL (44.3 vs 53.9 mm, p = 0.40), however, slow-pull technique was better in terms of CPT (30 vs 14.6, p < 0.001). Heterogeneity was present among the studies. Another limitation is the low number randomized control trials.

CONCLUSION

EUS-guided parenchymal liver biopsy is a good alternative to other methods of liver sampling. Using FNB needles with a slow-pull technique can provide better results.

A Comprehensive Narrative Review on the Evolving Role of Endoscopic Ultrasound in Focal Solid Liver Lesions Diagnosis and Management

The implications of endoscopic ultrasound (EUS) have expanded considerably in recent years to cover more fields in invasive gastroenterology practice, as both an investigative and therapeutic modality. The utility of EUS in the diagnosis and management of focal liver lesions has gained a special attractiveness recently. The EUS probe proximity to the liver and its excellent spatial resolution enables real-time images coupled with several enhancement techniques, such as contrast-enhanced (CE) EUS. Aside from its notable capability to execute targeted biopsies and therapeutic interventions, EUS has developed into a hopeful therapeutic tool for the management of solid liver lesions. Herein, we provide a comprehensive state-of-the-art review on the efficacy and safety of EUS in the diagnosis and management of focal solid liver lesions. Medline/PubMed and Embase database searches were conducted by two separate authors (T.K. and W.S.), all relevant studies were assessed, and relevant data was extracted and fully reported. EUS-guided diagnosis of focal liver lesions by sonographic morphologic appearance and cytological and histopathological finding of biopsies obtained via fine needle aspiration/biopsy have been shown to significantly improve the diagnosis of solid liver lesions compared with traditional imaging tools. Similarly, EUS-guided treatment has been shown to consistently have excellent technical success, high efficacy, and minor adverse events. The evolving valuable evidences of EUS utility might satisfy the unmet need of optimizing management of focal solid liver lesions.

A State-of-the-Art Review on the Evolving Utility of Endoscopic Ultrasound in Liver Diseases Diagnosis

Liver diseases are amongst the most common diseases worldwide and manifest as a parenchymatic and/or biliary injury due to several causes as well as focal liver lesions, ranging from benign to malignant ones. The diagnosis of liver diseases is based mainly on biochemical and advanced imaging studies and, when required, on liver biopsy. Endoscopic ultrasound (EUS), which combines endoscopy and ultrasonography, is one of the main examination techniques used in gastroenterology as it is applied to evaluate abnormalities in the lumen of the upper and lower gastrointestinal tract and to define pancreatic and hepato-biliary features, often in chronic patients. Given its high spatial resolution and its proximity to the liver, EUS is gaining popularity in the diagnostic work up of liver diseases. This is a comprehensive overview of the current literature on the diagnostic indications for EUS use in patients with liver diseases. We performed a MEDLINE\PubMed and Embase search, and all articles that were relevant, after reviewing abstracts, were assessed and the full text was analyzed to extract data regarding technical success, diagnostic yield, bioptic characteristics, and complications rate. EUS-guided imaging and biopsy techniques in liver diseases have shown consistent favorable promising results among the reports through the literature, with an excellent diagnostic yield and safety profile, especially in the context of focal lesions and portal hypertension. The application of EUS in the diagnosis of liver diseases is a promising technique and should be considered as a first-line therapeutic option in selected cases.

Endoscopic ultrasound in chronic liver disease

Endoscopic ultrasound (EUS) is a minimally invasive diagnostic and therapeutic modality with a number of established as well as evolving uses in patients with chronic liver disease. Compared to other diagnostic tools such as cross-sectional imaging or conventional endoscopy, EUS has been shown to increase diagnostic sensitivity and therapeutic success for many clinical scenarios and applications with a low rate of adverse events. In this review, we discuss and focus on the current and growing role of EUS in the evaluation and/or treatment of hepatobiliary masses, hepatic parenchymal disease, portal hypertension, esophageal and other varices, and indeterminate biliary strictures.

The role of EUS in diagnosis and treatment of liver disorders

Background and aim  Transabdominal ultrasound (US), computed tomographic scanning (CT) and magnetic resonance imaging (MRI) are established diagnostic tools for liver diseases. Percutaneous transhepatic cholangiography is used to perform hepatic interventional procedures including biopsy, biliary drainage procedures, and radiofrequency ablation. Despite their widespread use, these techniques have limitations. Endoscopic ultrasound (EUS), a tool that has proven useful for evaluating the mediastinum, esophagus, stomach, pancreas, and biliary tract, has an expanding role in the field of hepatology complementing the traditional investigational modalities. This review aimed to assess the current scientific evidence regarding diagnostic and therapeutic applications of EUS for hepatic diseases.

Endoscopic Ultrasound-Guided Liver Biopsy Using a Core Needle for Hepatic Solid Mass

Background/Aims

This study aimed to evaluate the feasibility and efficacy of endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) using a core needle for hepatic solid masses (HSMs). Additionally, the study aimed to assess factors that influence the diagnostic accuracy of EUS-FNB for HSMs.

Methods

A retrospective analysis of patients who underwent EUS-FNB for the pathological diagnosis of HSMs was conducted between January 2013 and July 2017. The procedure had been performed using core needles of different calibers. The assessed variables were mass size, puncture route, needle type, and the number of needle passes.

Results

Fifty-eight patients underwent EUS-FNB for the pathologic evaluation of HSMs with a mean mass size of 21.4±9.2 mm. EUS-FNB was performed with either a 20-G (n=14), 22-G (n=29) or a 25-G core needle (n=15). The diagnostic accuracy for this procedure was 89.7%, but both specimen adequacy for histology and available immunohistochemistry stain were 91.4%. The sensitivity and specificity of EUS-FNB were 89.7% and 100%, respectively. There was one case involving bleeding as a complication, which was controlled with endoscopic hemostasis. According to the multivariate analysis, no variable was independently associated with a correct final diagnosis.

Conclusions

EUS-FNB with core biopsy needle is a safe and highly accurate diagnostic option for assessing HSMs. There were no variable factors associated with diagnostic accuracy.

Miniaturized High-Resolution Integrated 360° Electronic Radial Ultrasound Endoscope for Digestive Tract Imaging

To improve the accuracy and operating flexibility of digestive diagnostic applications in situ, this paper demonstrates the design, fabrication, and evaluation of a miniaturized high-resolution integrated 360° electronic radial ultrasound endoscope. To improve the uniformity between elements of the radial array transducer, an optimal fabrication procedure based on a flexible matching layer was developed. The radial ultrasound endoscope has a 128.3° 5-million-pixel camera module integrated with an approximately 8-MHz 128-element radial ultrasonic array in a package with an outer diameter of 9.5 mm. The results showed that the array has a center frequency of 8.2 MHz, a -6-dB fractional bandwidth of 83.4%, and a two-way insertion loss of 39.62 dB at the center frequency. Annulus and wire phantoms can be distinctly imaged with the radial array. Printed eight-point font can be distinctly imaged with both a large view and a 3-18-mm depth of field in lumen short-range optical imaging. A porcine esophagus can be distinctly imaged in vitro with the integrated endoscope. The results indicate that the fabrication method based on a flexible matching layer can achieve high uniformity between elements of a radial array transducer. In addition, the proposed ultrasound endoscope demonstrates a good image resolution.

Diagnostic yield of endoscopic ultrasound-guided biopsy of focal liver lesions

Endoscopic ultrasonography (EUS) has become an indispensable method for diagnosis and therapeutic procedures in gastroenterology. As experience with this technique grows, new indications continue to emerge. Due to the vicinity of the transducer to the liver, endoscopic ultrasonography provides detailed images of the liver segments and its vascular and biliary structures. Endosonographers have made an effort to define a clinical role for endoscopic ultrasound in liver diseases; however, not much is known about endoscopic ultrasound guided fine needle aspiration (EUS-FNA) in hepatic focal lesions. This review summarizes the available evidence regarding the usefulness of endoscopic ultrasound-guided fine needle aspiration in patients with focal liver lesions.

Impact of endoscopic ultrasonography on diagnosis of pancreatic cancer

Accumulated evidence has revealed that endoscopic ultrasonography (EUS) has had a great impact on the clinical evaluation of pancreatic cancers. EUS can provide high-resolution images of the pancreas with a quality regarded as far surpassing that achieved on transabdominal ultrasound (US), computed tomography (CT), or magnetic resonance imaging (MRI). EUS is particularly useful for the detection of small pancreatic lesions, while EUS and its related techniques such as contrast-enhanced EUS (CE-EUS), EUS elastography, and EUS-guided fine needle aspiration (EUS-FNA) are also useful in the differential diagnosis of solid or cystic pancreatic lesions and the staging (T-staging, N-staging, and M-staging) of pancreatic cancers. In the diagnosis of pancreatic lesions, CE-EUS and EUS elastography play a complementary role to conventional EUS. When sampling is performed using EUS-FNA, CE-EUS and EUS elastography provide information on the target lesions. Thus, conventional EUS, CE-EUS, EUS elastography, and EUS-FNA are essential in the clinical investigation of pancreatic cancer.

Recent advancement in EUS-guided fine needle sampling

EUS-guided tissue acquisition technique plays an essential role for evaluation of gastrointestinal tumors. Several components affect the yield of EUS-guided tissue acquisition outcomes such as sampling techniques, use of ROSE (rapid onsite evaluation), training and experience, and needle designs. In this review we discuss advancement in EUS-guided fine needle sampling.

A quarter century of EUS-FNA: Progress, milestones, and future directions

Tissue acquisition using EUS has considerably evolved since the first EUS-FNA was reported 25 years ago. Its introduction was an important breakthrough in the endoscopic field. EUS-FNA has now become a part of the diagnostic and staging algorithm for the evaluation of benign and malignant diseases of the gastrointestinal tract and of the organs in its proximity, including lung diseases. This review aims to present the history of EUS-FNA development and to provide a perspective on the recent developments in procedural techniques and needle technologies that have significantly extended the role of EUS and its clinical applications. There is a bright future ahead for EUS-FNA in the years to come as extensive research is conducted in this field and various technologies are continuously implemented into clinical practice.

Endoscopic ultrasound guided brush/fine-needle aspiration cytology: A 15-month study

BACKGROUND

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has become increasingly popular for the diagnosis and staging of gastrointestinal diseases and peri-gastrointestinal lesions. The application of FNA/Brush has dramatically expanded the clinical utility of EUS.

AIMS AND OBJECTIVE

To evaluate the diagnostic accuracy, study the spectrum of lesions encountered in EUS-FNAC/brush cytology of gastrointestinal and peri-gastrointestinal lesions.

MATERIALS AND METHODS

Total of 124 patients during the period from August 2015 to November 2016 was included in the study. Routine staining was done.

RESULTS

A total of 124 cases were studied with 86% (107 cases) being satisfactory for evaluation. M:F ratio was 1:1.03, mean age of 50.5 years. The most common site was common bile duct (CBD) (37%) followed by lymph node (21%), pancreas (17.7%), esophagus (17%), stomach (3.5%), liver (1.8%), gallbladder (1%), and spleen (1%). In total, 53.4% lesions were benign, in 6.5% atypical cells were seen, 12.1% were suspicious for malignancy, and 28% cases were positive for malignancy. Follow-up was available in 102 cases with cyto-histopathological concordance rate of 90%.

CONCLUSION

EUS-FNA/Brush is a reliable, sensitive, specific and minimally invasive way to establish a diagnosis. It can be utilized as a pre-operative procedure for the management of many intra-abdominal lesions and prevent unnecessary invasive procedures.

Utility of endoscopic ultrasound and endoscopy in diagnosis and management of hepatocellular carcinoma and its complications: What does endoscopic ultrasonography offer above and beyond conventional cross-sectional imaging?

Hepatocellular carcinoma constitutes over 90% of the primary liver tumors, the rest being cholangiocarcinoma. It has an insidious presentation, which is responsible for the delayed presentation. Hence, the management strategy relies on screening to diagnose it an early stage for curative resection and/or treatment with local ablative techniques or chemotherapy. However, even with different screening programs, more than 60% of tumors are still detected at an advanced stage, leading to an unchanged mortality rate, thereby implying a room for improvement in the screening and diagnostic process. In the last few years, there has been evolution of utility of endoscopy, specifically endoscopic ultrasonography along with Fine needle aspiration, for this purpose, which we comprehensively review in this article.

EUS anatomy of the liver segments

Clinical applications of EUS for the liver have been recently increasing. They include the screening and diagnosis of liver parenchymal disease and malignant tumors as well as EUS-guided interventions such as hepaticogastrostomy, tumor ablation therapy, and portal pressure gradient measurement. Although the segmental localization of the targeted tumor, bile duct, and vessel in the liver is important to complete these procedures, little information is available regarding hepatic segmental anatomy on EUS. The liver can be visualized with EUS by transgastric and transduodenal scanning, and the EUS determination of segmental location can be achieved using various anatomical landmarks. Identification of the right posterior segments is, however, technically difficult because they are located far from the stomach and duodenum. In the present review, we describe the normal anatomy of liver segments using linear EUS.

Applications of Endoscopic Ultrasonography in Pancreatic Cancer

Background

Accurate staging of pancreatic cancer is essential for surgical planning and for identification of locally advanced and metastatic disease that is incurable by surgery. Advances in endoscopic sonography (EUS), computed tomography (CT), and positron emission tomography have improved the accuracy of staging and reduced the number of incomplete surgical resections. Tissue acquisition is necessary in nonsurgical cases when chemoradiotherapy is considered. The complex regional anatomy of the pancreas makes cytologic diagnosis of malignancy at this region difficult without exploratory surgery. Although CT-guided fine-needle aspiration (FNA) is used for this purpose, reports of an increased risk of peritoneal dissemination of cancer cells and a false-negative rate of nearly 20% make this a poor choice. The ability to position the EUS-transducer in direct proximity to the pancreas by means of the stomach and duodenum, combined with the use of FNA, increases the specificity of EUS in detecting pancreatic malignancies.

Methods

The current literature regarding the accuracy of EUS with FNA in the evaluation of pancreatic cancer is reviewed.

Results

EUS accuracy ranges from 78% to 94% for tumor staging and from 64% to 82% for nodal staging. EUS also enables FNA of lesions that are too small to be identified by CT or MRI or too well encased by surrounding vascular structures to safely allow percutaneous biopsy. The accuracy for detecting invasion into the superior mesenteric artery and vein is lower than that for detecting portal or splenic vein invasion, especially for large tumors. EUS permits delivery of localized therapy such as celiac plexus neurolysis for pain control and direct intra-lesional injection of antitumor therapy.

Conclusions

EUS in combination with FNA is a highly accurate method of preoperative staging of pancreatic cancer, especially those too small to be characterized by CT or MRI, and it has the ability to obtain cytological confirmation of pancreatic cancer.

Fabrication and Performance of a Miniaturized and Integrated Endoscope Ultrasound Convex Array for Digestive Tract Imaging

OBJECTIVE

this work presents the design, fabrication, and testing of a miniaturized and integrated ultrasound endoscope for use as an in situ digestive diagnostic device to facilitate real-time ultrasound guidance of intervention treatments.

METHODS

we designed an optimal structure to integrate an auto-focus 5-megapixel camera module with an 8-MHz, 64-element curvilinear ultrasonic array in one miniaturized package. A novel three-axis auto-focusing voice coil motor (VCM) was designed and manufactured for the camera module to move the lens position for auto-focusing and to adjust the lens tilt.

RESULTS

the results showed that the array had a center frequency of 8.09 MHz and a -6-dB fractional bandwidth of 83%. At the center frequency, the two-way insertion loss was 40.6 dB. Endoscopic ultrasound imaging demonstrated satisfactory performance for imaging an anthropomorphic phantom of the esophagus. By slightly adjusting the tilt angle of the optical axis of the lens, the optical image captured by the auto-focusing lens obtained improved definition regardless of changes in the view angle of the camera with respect to the objects being captured.

CONCLUSION

the integrated convex ultrasound endoscope, possessing minimal size, improved optical imaging definition, and good ultrasound imaging performance, can become a useful tool in digestive tract imaging.

SIGNIFICANCE

the miniaturized and integrated convex ultrasound endoscope can facilitate real-time ultrasound intervention guidance, reducing risks associated with the operation.

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.

In vivo cytological observation of liver and spleen by using high-resolution microendoscopy system under endoscopic ultrasound guidance: A preliminary study using a swine model

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is useful to obtain specimens from lesions underlying deep parts of the liver and spleen. However, the development of novel ancillary techniques must be explored to reduce the number of needle passes and potential adverse effects during this procedure. We conducted an animal study using a swine to demonstrate technical feasibility of in vivo cytological observation of liver and spleen using the high-resolution microendoscopy (HRME) system under EUS guidance. We successfully performed the study. No significant acute adverse events occurred during the procedure. The HRME system could obtain clear images representing cytology-level morphology of spleen and liver. Hence, it is found out that in vivo cytological observation of liver and spleen using the HRME system under EUS guidance is technically feasible.

EUS-guided liver biopsy for parenchymal disease: a comparison of diagnostic yield between two core biopsy needles

BACKGROUND AND AIMS

EUS-guided biopsy of the liver has a variable diagnostic accuracy and specimen adequacy. A new core biopsy needle has been developed that may improve performance. The objective of this study was to compare the diagnostic yield of a new core biopsy needle with the previous standard needle.

METHODS

In this cross-sectional study, consecutive patients who underwent EUS-guided core liver biopsy over a 7-year period for suspected parenchymal disease were prospectively evaluated. Between 2007 and 2011, all biopsies were performed with a 19-gauge Tru-cut biopsy needle (Quick-core [QC]), whereas a novel reverse bevel needle (PC) was used exclusively from 2011 to 2014. All specimens were examined by 1 of 3 experienced, blinded pathologists for the following: presence of visible core, aggregate specimen length, number of complete portal tracts, and specimen adequacy.

RESULTS

A total of 75 patients (mean age 51 years, 51 female) underwent liver biopsy by using the QC (n = 45) or PC (n = 30) needle. The QC and PC groups had similar demographics, indications for EUS, indications for liver biopsy, and liver findings on EUS. Compared with those of the QC, biopsies with the PC required fewer passes (median 2 vs 3; P < .0001) but produced longer aggregate length (median 20 mm vs 9 mm; P < .0001) with more complete portal tracts (median 5 vs 2; P = .0003) and adequate specimens (P < .01). Two patients had abdominal pain after liver biopsy with the QC needle.

CONCLUSIONS

Compared with the QC needle, EUS-guided core liver biopsy with the PC needle produced longer aggregate length, more complete portal tracts, and more adequate specimens despite fewer passes (Clinical trial registration number: NCT00586313.).

Hepatic applications of endoscopic ultrasound: Current status and future directions

The diagnosis and staging of various gastrointestinal malignancies have been made possible with the use of endoscopic ultrasound, which is a relatively safe procedure. The field of endoscopic ultrasound is fast expanding due to advancements in therapeutic endoscopic ultrasound. Though various studies have established its role in gastrointestinal malignancies and pancreatic conditions, its potential in the field of hepatic lesions still remains vastly untapped. In this paper the authors attempt to review important and landmark trials, case series and case studies involving hepatic applications of endoscopic ultrasound, thus not only providing an overview of utilization of endoscopic ultrasound in various liver conditions but also speculating its future role.

Endoscopic ultrasound-guided liver biopsy

Liver biopsy remains the cornerstone in the diagnosis and management of liver disorders. Results of liver biopsy can often drive therapeutic decision-making. Unfortunately, studies have shown conventional biopsy techniques to carry significant sampling variability that can potentially impact patient care. Endoscopic ultrasound (EUS) is gaining traction as an alternative method of biopsy. For parenchymal disease, it can decrease sampling variability. It offers a more targeted approach for focal lesions. Its diagnostic yield and limited adverse event profile make it a promising approach for liver biopsy.