On-site Cytopathologist Research Articles

Enhancing Diagnostic Yield of EUS-Guided FNA Through On-site Cytopathology

Enhancing Diagnostic Yield of EUS-Guided FNA Through On-site Cytopathology

Strategic insights into the cultivation of pancreatic cancer organoids from endoscopic ultrasonography-guided biopsy tissue

BACKGROUND The frequent suboptimal efficacy of endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) to culture pancreatic cancer (PC) organoids (PCOs) poses a major challenge in the advancement of personalized medicine for advanced PC. AIM To explore how to obtain appropriate puncture tissues from EUS-FNB and optimize the strategy for efficiently constructing PCOs, providing an efficient tool for the advancement of personalized medicine. METHODS Patients who underwent EUS-FNB for the diagnosis of PC tissue were prospectively enrolled. We refined the endoscopic biopsy procedures and organoid cultivation techniques. All tissue specimens verified by on-site pathological assessment were cultured in a semi-suspended medium in a microfluidic environment. We assessed differences in PCOs cultured beyond and below five generations examining patient demographics, specimen and organoid attributes, and the sensitivity of organoids to a panel of clinical drugs through cell viability assays. RESULTS In this study, 16 patients with PC were recruited, one sample was excluded because onsite cytopathology showed no tumor cells. Successful organoid generation occurred in 93.3% (14 of 15) of the EUS-FNB specimens, with 60% (9 of 15) sustaining over five generations. Among these patients, those with a history of diabetes, familial cancer, or larger tumors exhibited enhanced PCO expandability. The key factors influencing long-term PCOs expansion included initial needle sample quality (P = 0.005), rapid initiation of organoid culture post-isolation (P ≤ 0.001), and high organoid activity (P = 0.031). Drug sensitivity analysis revealed a partial response in two patients following therapeutic intervention and surgery and stable disease in four patients, indicating a moderate correlation between organoid response and clinical outcomes. CONCLUSION Optimal initial needle sampling, rapid and precise biopsy sample processing, process isolated samples as soon as possible, and sufficient cellular material are crucial for successful cultivating PCOs. High organoid activity is an important factor in maintaining their long-term expansion, which is essential for shortening the time of drug sensitivity analysis and is the basis of PC research.

Effectiveness of data-augmentation on deep learning in evaluating rapid on-site cytopathology at endoscopic ultrasound-guided fine needle aspiration

Rapid on-site cytopathology evaluation (ROSE) has been considered an effective method to increase the diagnostic ability of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA); however, ROSE is unavailable in most institutes worldwide due to the shortage of cytopathologists. To overcome this situation, we created an artificial intelligence (AI)-based system (the ROSE-AI system), which was trained with the augmented data to evaluate the slide images acquired by EUS-FNA. This study aimed to clarify the effects of such data-augmentation on establishing an effective ROSE-AI system by comparing the efficacy of various data-augmentation techniques. The ROSE-AI system was trained with increased data obtained by the various data-augmentation techniques, including geometric transformation, color space transformation, and kernel filtering. By performing five-fold cross-validation, we compared the efficacy of each data-augmentation technique on the increasing diagnostic abilities of the ROSE-AI system. We collected 4059 divided EUS-FNA slide images from 36 patients with pancreatic cancer and nine patients with non-pancreatic cancer. The diagnostic ability of the ROSE-AI system without data augmentation had a sensitivity, specificity, and accuracy of 87.5%, 79.7%, and 83.7%, respectively. While, some data-augmentation techniques decreased diagnostic ability, the ROSE-AI system trained only with the augmented data using the geometric transformation technique had the highest diagnostic accuracy (88.2%). We successfully developed a prototype ROSE-AI system with high diagnostic ability. Each data-augmentation technique may have various compatibilities with AI-mediated diagnostics, and the geometric transformation was the most effective for the ROSE-AI system.

Safety and Diagnostic Efficacy of Image-Guided Biopsy of Small Renal Masses.

Image-guided renal mass biopsy is gaining increased diagnostic acceptance, but there are limited data concerning the safety and diagnostic yield of biopsy for small renal masses (≤4 cm). This study evaluated the safety, diagnostic yield, and management after image-guided percutaneous biopsy for small renal masses. A retrospective IRB-approved study was conducted on patients who underwent renal mass biopsy for histopathologic diagnosis at a single center from 2015 to 2021. Patients with a prior history of malignancy or a renal mass >4 cm were excluded. Descriptive statistics were used to summarize patient demographics, tumor size, the imaging modality used for biopsy, procedure details, complications, pathological diagnosis, and post-biopsy management. A biopsy was considered successful when the specimen was sufficient for diagnosis without need for a repeat biopsy. Complications were graded according to the SIR classification of adverse events. A chi-squared test (significance level set at p ≤ 0.05) was used to compare the success rate of biopsies in different lesion size groups. A total of 167 patients met the inclusion criteria. The median age was 65 years (range: 26-87) and 51% were male. The median renal mass size was 2.6 cm (range: one-four). Ultrasound was solely employed in 60% of procedures, CT in 33%, a combination of US/CT in 6%, and MRI in one case. With on-site cytopathology, the median number of specimens obtained per procedure was four (range: one-nine). The overall complication rate was 5%. Grade A complications were seen in 4% (n = 7), consisting of perinephric hematoma (n = 6) and retroperitoneal hematoma (n = 1). There was one grade B complication (0.5%; pain) and one grade D complication (0.5%; pyelonephritis). There was no patient mortality within 30 days post-biopsy. Biopsy was successful in 88% of cases. A sub-group analysis showed a success rate of 85% in tumors <3 cm and 93% in tumors ≥3 cm (p = 0.01). Pathological diagnoses included renal cell carcinoma (65%), oncocytoma (18%), clear cell papillary renal cell tumors (9%), angiomyolipoma (4%), xanthogranulomatous pyelonephritis (1%), lymphoma (1%), high-grade papillary urothelial carcinoma (1%), and metanephric adenoma (1%), revealing benign diagnosis in 30% of cases. The most common treatment was surgery (40%), followed by percutaneous cryoablation (22%). In total, 37% of patients were managed conservatively, and one patient received chemotherapy. This study demonstrates the safety and diagnostic efficacy of image-guided biopsy of small renal masses. The diagnostic yield was significantly higher for masses 3-4 cm in size compared to those <3 cm. The biopsy results showed a high percentage of benign diagnoses and informed treatment decisions in most patients.

Real-World Diagnostic Accuracy of the On-Site Cytopathology Advance Report (OSCAR) Procedure Performed in a Multidisciplinary One-Stop Breast Clinic.

Fine-needle aspiration (FNA) cytology has been widely used for the diagnosis of breast cancer lesions with the objective of differentiating benign from malignant masses. However, the occurrence of unsatisfactory samples and false-negative rates remains a matter of concern. Major improvements have been made thanks to the implementation of rapid on-site evaluation (ROSE) in multidisciplinary and integrated medical settings such as one-stop clinics (OSCs). In these settings, clinical and radiological examinations are combined with a morphological study performed by interventional pathologists. The aim of our study was to assess the diagnostic accuracy of the on-site cytopathology advance report (OSCAR) procedure on breast FNA cytologic samples in our breast OSC during the first three years (April 2004 till March 2007) of its implementation. To this goal, we retrospectively analyzed a series of 1820 breast masses (1740 patients) radiologically classified according to the American College of Radiology (ACR) BI-RADS lexicon (67.6% being either BI-RADS 4 or 5), sampled by FNA and immediately diagnosed by cytomorphology. The clinicoradiological, cytomorphological, and histological characteristics of all consecutive patients were retrieved from the hospital computerized medical records prospectively registered in the central information system. Histopathological analysis and ultrasound (US) follow-up (FU) were the reference diagnostic tests of the study design. In brief, we carried out either a histopathological verification or an 18-month US evaluation when a benign cytology was concordant with the components of the triple test. Overall, histology was available for 1138 masses, whereas 491 masses were analyzed at the 18-month US-FU. FNA specimens were morphologically nondiagnostic in 3.1%, false negatives were observed in 1.5%, and there was only one false positive (0.06%). The breast cancer prevalence was 62%. Diagnostic accuracy measures of the OSCAR procedure with their 95% confidence intervals (95% CI) were the following: sensitivity (Se) = 97.4% (96.19-98.31); specificity (Sp) = 94.98% (92.94-96.56); positive predictive value (PPV) = 96.80% (95.48-97.81); negative predictive value (NPV) = 95.91% (94.02-97.33); positive likelihood ratio (LR+) = 19.39 (13.75-27.32); negative predictive ratio (LR-) = 0.03 (0.02-0.04), and; accuracy = 96.45% (95.42-97.31). The respective positive likelihood ratio (LR+) for each of the four categories of cytopathological diagnoses (with their 95% CI) which are malignant, suspicious, benign, and nondiagnostic were 540 (76-3827); 2.69 (1.8-3.96); 0.03 (0.02-0.04); and 0.37 (0.2-0.66), respectively. In conclusion, our study demonstrates that the OSCAR procedure is a highly reliable diagnostic approach and a perfect test to select patients requiring core-needle biopsy (CNB) when performed by interventional cytopathologists in a multidisciplinary and integrated OSC setting. Besides drastically limiting the rate of nondiagnostic specimens and diagnostic turn-around time, OSCAR is an efficient and powerful first-line diagnostic approach for patient-centered care.

Application of artificial intelligence to digital-rapid on-site cytopathology evaluation during endoscopic ultrasound-guided fine needle aspiration: A proof-of-concept study.

During endoscopic ultrasound-guided fine needle aspiration (EUS-FNA), cytopathology with rapid on-site evaluation (ROSE) can improve diagnostic yield and accuracy. However, ROSE is unavailable in most Asian and European institutions because of the shortage of cytopathologists. Therefore, developing computer-assisted diagnostic tools to replace manual ROSE is crucial. Herein, we reported the validation of an artificial intelligence (AI)-based model (ROSE-AI model) to substitute manual ROSE during EUS-FNA. A total of 467 digitized images from Diff-Quik (D&F)-stained EUS-FNA slides were divided into training (3642 tiles from 367 images) and internal validation (916 tiles from 100 images) datasets. The ROSE-AI model was trained and validated using training and internal validation datasets, respectively. The specificity was emphasized while developing the model. Then, we evaluated the AI model on a 693-image external dataset. We assessed the performance of the AI model to detect cancer cells (CCs) regarding the accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). The ROSE-AI model achieved an accuracy of 83.4% in the internal validation dataset and 88.7% in the external test dataset. The sensitivity and PPV were 79.1% and 71.7% in internal validation dataset and 78.0% and 60.7% in external test dataset, respectively. We provided a proof of concept that AI can be used to replace manual ROSE during EUS-FNA. The ROSE-AI model can address the shortage of cytopathologists and make ROSE available in more institutes.

How to Perform Endoscopic Ultrasound-Guided Fine Needle Aspiration/Biopsy of Pancreatic Lesions?

A endoscopic ultrasound-guided fine needle aspiration/biopsy (EUS-FNA/B) of pancreatic solid and cystic lesions is a modality, which huge numbers of articles has showed its high diagnostic accuracy. The degree of technical difficulty, size and type of needle, endoscopic technique, use of suction to aspirate tissue, use or not use of a stylet in the needle assembly, maneuvers to have high quality tissue, availability of an on-site cytopathologist, and, finally, end sonographer’s experience and skills who does the procedure have impact on the EUS-FNA results. Standard 19-G and 22-G fine-needle aspiration needles with or without high negative pressure have proven to be reliable in obtaining high-quality histologic samples in various indications. Twenty-five-gauge (25-gauge) needles provide better diagnostic yield when sampling pancreatic lesions compared with 22-G needles. The novel 19-G and 22-G ProCore™ needles have demonstrated a high yield in obtaining histologic samples, whereas 25-G. ProCore™ seems unsuitable for histology. A cytopathology service should be involved early in the planning process for establishing an EUS-FNA service. Data on the newly developed 20-G ProCore™, SharkCore® and Acquire® needles are limited, but appear very promising. Use of the stylet does not increase the yield of endoscopic ultrasonography-fine-needle aspiration and is more cumbersome to use. In perspective, endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is expected to refine differential diagnostic capabilities, favor widespread EUS utilization, and pave the road to targeted therapies and monitoring of treatment response. Approximately 3 to 5 passes should be sufficient to obtain a diagnosis. We need further studies for assessment of the use of Suction, Capillary (“Slow-Pull”), Wet and Fanning techniques.

OPTIMIZING THE RESECTION PATHWAY: CAN MINIMALLY INVASIVE DIAGNOSIS AND SURGERY (MIDAS) GUIDE PATIENT SELECTION?

OPTIMIZING THE RESECTION PATHWAY: CAN MINIMALLY INVASIVE DIAGNOSIS AND SURGERY (MIDAS) GUIDE PATIENT SELECTION?

Diagnostic performance of endoscopic ultrasound-guided tissue acquisition by EUS-FNA versus EUS-FNB for solid pancreatic mass without ROSE: a retrospective study

BackgroundEndoscopic ultrasound-guided tissue acquisition (EUS-TA) is an established diagnostic procedure for solid pancreatic mass. However, the diagnostic yield between fine-needle aspiration (FNA) and fine-needle biopsy (FNB) remains unclear. We aimed to evaluate and compare the diagnostic yields between FNA and FNB using conventional FNA and Franseen needles of the same size 22-gauge needle, in patients with solid pancreatic mass who underwent EUS-TA without rapid onsite cytopathology evaluation (ROSE).MethodsAll cases of EUS-TA by FNA or FNB for solid pancreatic mass between January 2017 and October 2020 in a single-centre university hospital were retrospectively reviewed. All procedures were performed without an onsite cytologist. Before the endoscopist finished the procedure, macroscopic onsite evaluation (MOSE) was confirmed. The diagnostic yield and the average number of needle passes between FNB and FNA were then compared.ResultsA total of 151 patients (FNA, n = 77; FNB, n = 74) with solid pancreatic mass detected by cross-sectional imaging underwent EUS-TA. The mean age was 62.3 ± 12.8 years, with 88 (58.3%) males. Age, sex, mass location, tumour size and disease stage from imaging were not significantly different between the two groups. The diagnostic performance was higher in EUS-FNB (94.6%) than in EUS-FNA (89.6%). The mean number of needle passes was clearly fewer in FNB than in FNA (2.8 vs. 3.8, p < 0.001). The total procedure time was shorter in FNB (34.7 min) than in FNA (41 min). The adverse event rate between FNB and FNA was not significantly different.ConclusionsThe diagnostic yield of solid pancreatic mass was higher in FNB using the Franseen needle than in FNA using the conventional FNA needle in a centre where ROSE is unavailable, without serious adverse event. In addition, FNB had fewer needle passes and shorter total procedure time.

A deep learning-based segmentation system for rapid onsite cytologic pathology evaluation of pancreatic masses: A retrospective, multicenter, diagnostic study.

SummaryBackgroundWe aimed to develop a deep learning-based segmentation system for rapid on-site cytopathology evaluation (ROSE) to improve the diagnostic efficiency of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) biopsy.MethodsA retrospective, multicenter, diagnostic study was conducted using 5345 cytopathological slide images from 194 patients who underwent EUS-FNA. These patients were from Nanjing Drum Tower Hospital (109 patients), Wuxi People's Hospital (30 patients), Wuxi Second People's Hospital (25 patients), and The Second Affiliated Hospital of Soochow University (30 patients). A deep convolutional neural network (DCNN) system was developed to segment cell clusters and identify cancer cell clusters with cytopathological slide images. Internal testing, external testing, subgroup analysis, and human–machine competition were used to evaluate the performance of the system.FindingsThe DCNN system segmented stained cells from the background in cytopathological slides with an F1-score of 0·929 and 0·899–0·938 in internal and external testing, respectively. For cancer identification, the DCNN system identified images containing cancer clusters with AUCs of 0·958 and 0·948–0·976 in internal and external testing, respectively. The generalizable and robust performance of the DCNN system was validated in sensitivity analysis (AUC > 0·900) and was superior to that of trained endoscopists and comparable to cytopathologists on our testing datasets.InterpretationThe DCNN system is feasible and robust for identifying sample adequacy and pancreatic cancer cell clusters. Prospective studies are warranted to evaluate the clinical significance of the system.FundingJiangsu Natural Science Foundation; Nanjing Medical Science and Technology Development Funding; National Natural Science Foundation of China.

Efficacy and safety of CT-guided percutaneous fine needle aspiration and biopsy for malignant pulmonary lesions

Background: CT-guided percutaneous transthoracic fine needle aspiration (FNA) and core biopsy (CB) are commonly used to characterise lung lesions. There is conflicting information on which method is superior and wide variation in reported complication rates. Our objectives were to establish the efficacy and safety of percutaneous CT-guided FNA and CB in the diagnosis of malignant lung lesions. Methods: This retrospective study included patients who underwent CT-guided percutaneous FNA and/or CB for lung parenchymal lesions at Kasturba Medical College Mangalore, from January 2013 to December 2020. Ethical clearance was obtained from the Institutional Ethics Committee. Efficacy was determined by the adequacy of samples, sensitivity, specificity and diagnostic accuracy. Safety was assessed using the incidence of complications. Results: A total of 326 patients underwent both FNA and CB, and 49 underwent FNA alone. Adequate samples were obtained in 82.9% of FNA cases and 95.7% of CB cases. Considering biopsy as the gold standard, the sensitivity, specificity and diagnostic accuracy of FNA for malignancy were 95.19%, 80% and 91.27%, respectively. Kappa agreement between the two methods was substantial (0.767). Pneumothorax was the only complication observed, and was seen in 31 patients (8.2%), of which only one required chest tube drainage. The incidence of pneumothorax was significantly higher in patients with pre-existing lung disease such as COPD/emphysema (p value 0.000), patients with smaller lesions (p = 0.009), and deeper lesions from the pleura (p &lt;0.0001). Conclusions: FNA and CB are both safe and effective procedures. In the absence of an onsite cytopathologist, we recommend a combination of both techniques.

Optimal Techniques for EUS-Guided Fine-Needle Aspiration of Pancreatic Solid Masses at Facilities without On-Site Cytopathology: Results from Two Prospective Randomised Trials.

Background: EUS-guided fine-needle aspiration (EUS-FNA) has emerged as the primary modality for the cytologic diagnosis of pancreatic solid masses. The aim of this study is to determine whether technical factors including suction (S), non-suction (NS), capillary sampling with stylet slow-pull (CSSS), and the number of needle actuations (to-and-fro needle movements) may affect the accuracy of EUS-FNA for pancreatic solid masses at facilities without on-site cytopathology. Methods: The diagnostic yield of malignancy, blood contamination and cellularity at each sample acquired from EUS-FNA with or without S and different numbers of actuation (10, 15 and 20) were measured (study I). The optimal actuation number was determined and a head-to-head comparison trial between S and CSSS was performed (study II). Results: In study I, significant blood contamination was seen using S with 20 compared with 15 actuations (p = 0.002). Diagnostic yield of malignancy was not significantly different between 10, 15, and 20 actuations with S, whereas it was statistically higher for 15 actuations compared with 10 actuations with NS (p = 0.001). In study II, no difference was noted in diagnostic yield with 15 actuations between S and CSSS (88% vs. 90%, p = 0.74). Conclusions: Increasing actuation in NS resulted in a better diagnostic yield for EUS-FNA without significant blood contamination, whereas increasing actuation in S did not change the diagnostic yield of EUS-FNA while causing significant blood contamination. With 15 actuations, the diagnostic yield was comparable between S and CSSS.

Transvaginal Ultrasound-Guided Fine-Needle Aspiration Biopsy of Pelvic Lesions.

To assess adequacy of transvaginal ultrasound-guided fine-needle aspiration biopsy (TVUS-FNAB) for pathologic diagnosis of pelvic masses performed using onsite cytopathology consultation. In this Institutional Review Board approved, Health Insurance Portability and Accountability Act (HIPAA) compliant study, radiology records were retrospectively queried to identify patients who underwent TVUS-FNAB of a pelvic mass over a 11-year duration. TVUS-FNAB adequacy was determined by correlating cytopathology results with transvaginal ultrasound-guided core-needle biopsy (TVUS-CNB) or surgical pathology results when available, and with clinical diagnostic confidence when additional pathology confirmation was not available. Secondary analysis included patient age, history of hysterectomy, or pelvic malignancy. Target-specific features analyzed included mass size, depth, location, and final pathologic diagnosis. Sixty patients underwent TVUS-FNAB of pelvic masses, 43 of which underwent FNAB only and 17 underwent both TVUS-FNAB and TVUS-CNB during the same procedure. TVUS-FNAB alone was adequate for diagnosis in 51 (85%) cases and addition of core-needle biopsy (CNB) achieved a diagnosis in additional 4 patients, increasing overall diagnostic accuracy to 92% (55/60). FNAB inadequacy had statistically significant association with increasing mass depth, occurrence of a minor intraprocedural complication, and decision to perform a CNB (P <.05). Number of FNAB passes, mass size, history of hysterectomy, and final diagnosis were not statistically significant predictors of FNAB adequacy. TVUS-FNAB has a high specimen adequacy rate when performed with an onsite cytopathologist and can be considered first-line approach for image-guided sampling of pelvic lesions with option to add CNB if preliminary cytopathologic review does not confirm sample adequacy.

Comparison of contrast-enhanced versus conventional EUS-guided FNA/fine-needle biopsy in diagnosis of solid pancreatic lesions: a randomized controlled trial

Contrast-enhanced harmonic EUS (CEH-EUS) is useful in the differential diagnosis of solid pancreatic lesions (SPLs). However, there is lack of verification about the usefulness of CEH-EUS-guided FNA/fine-needle biopsy (FNB) sampling. This study aimed to investigate the usefulness of CEH-EUS-guided FNA/FNB sampling without on-site cytopathology. Patients with SPLs were prospectively enrolled and randomly assigned (1:1) to 2 parallel groups, the interventional group (CEH-EUS) or the control group (conventional EUS). The diagnostic sensitivity and optimal number of needle passes for pathologic diagnosis were investigated and compared between groups. Two hundred forty patients were enrolled from March 2016 to September 2019, with 120 patients assigned to each group. Pancreatic malignancies and neuroendocrine tumors were found in 202 (90.83%) and 9 (3.75%) patients, respectively. There was no statistically significant difference between the groups in terms of age, sex, lesion size (30.96 ± 12.09mm in the CEH-EUS group vs 33.09 ± 16.39mm in the conventional EUS group; P= .252), lesion location, adverse event rate, and disease distribution. The diagnostic sensitivity values in the CEH-EUS and conventional EUS groups were 85.8% and 88.3%, respectively (P= .564). All patients in the conventional EUS group and most in the CEH-EUS group received a pathologic diagnosis within 3 needle passes. Diagnostic sensitivity for SPLs was not different between the CEH-EUS and conventional EUS groups, and no independent factors were found that could improve diagnostic sensitivity. CEH-EUS-guided FNA/FNB sampling does not need to be used routinely and may be selectively considered for small, indeterminate lesions. (Clinical trial registration number: KCT 0001840.).

A Prospective, Randomised Controlled Trial Investigating the Diagnostic Sensitivity of Contrast‐Enhanced Harmonic Endoscopic Ultrasound-Guided Versus Conventional Endoscopic Ultrasound‐Guided Fine-Needle Aspiration/Biopsy for Solid Pancreatic Lesions

Background: Contrast‐enhanced harmonic endoscopic ultrasound (CEH‐EUS) is useful in the differential diagnosis of solid pancreatic lesions (SPLs). This study aimed to investigate the usefulness of CEH‐EUS-guided fine-needle aspiration/biopsy (FNA/B), without on-site cytopathology. Methods: This randomised controlled trial was conducted at two university hospitals in Korea. Patients with SPLs were prospectively enrolled and randomly assigned (1:1) using a table of random sampling numbers, to two parallel groups, the interventional group (CEH-EUS) or the control group (conventional EUS). The investigators, endoscopists, patients, and pathologists were unmasked to the group assigned. The diagnostic sensitivity and optimal number of needle passes for pathologic diagnosis were investigated and compared between groups. Clinical trial number: KCT0001840. Findings: In total, 252 patients with SPLs were screened and 240 were enrolled from March 2016 to September 2019, with 120 patients assigned to each group. Pancreatic malignancies and neuroendocrine tumours were found in 202 (90·83%) and nine (3·75%) patients, respectively. There was no statistically significant difference between the groups in terms of age, sex, lesion size (30·96±12·09 mm in the CEH-EUS group vs 33·09±16·39 mm in the conventional EUS group; p=0·252), location, adverse event rate (2·5% vs 2·5%; p=0·999), and disease distribution (malignancy, neuroendocrine tumour, and benign masses, p=0·395). The diagnostic sensitivity values in the CEH-EUS and conventional EUS groups were 85·8% and 88·3%, respectively (p=0·564). All the patients in the conventional EUS group and most of those in the CEH-EUS group received a pathological diagnosis within three needle passes. Interpretation: This prospective, randomised trial showed that the diagnostic sensitivity for SPLs was not different between the CEH‐EUS and conventional EUS groups, and there were no independent factors that could improve diagnostic sensitivity. CEH-EUS-guided FNA/B will not need to be used routinely for the diagnosis of SPLs. CEH-EUS may be selectively considered in small, indeterminate lesion. Trial Registration: (Clinical trial registration at https://cris.nih.go.kr/cris; KCT0001840) Funding Statement: None. Declaration of Interests: There are no conflicts of interest to declare. Ethics Approval Statement: This study was approved by the Institutional Review Board (GAIRB2016-026) and conducted in accordance with the principles set forth in the Declaration of Helsinki. Written informed consent was obtained from all patients.

S3239 Evaluation of Sensitivity and Diagnostic Accuracy of Endoscopic Ultrasound for Diagnosis of Solid Pancreatic Lesions

INTRODUCTION: Endoscopic ultrasonography with fine needle aspiration/biopsy (EUS-FNA/FNB) facilitates a minimally invasive approach to obtaining pancreatic tissue for the workup of possible malignancies. The American Society of Gastrointestinal Endoscopy (ASGE) has set the benchmark for EUS-FNA/FNB to have a diagnostic rate of >75% and a sensitivity of >85% for solid pancreatic masses. The aim of this study is to assess the real-world rates of diagnostic accuracy, sensitivity and specificity of EUS-FNA for solid pancreatic masses, and factors associated with higher accuracy and sensitivity. METHODS: We conducted a retrospective chart review of all adult patients who underwent EUS-FNA/FNB at an academic level-1 trauma center in southeastern New England between April 2015 and March 2020. Patients were selected based on CPT billing codes for EUS with FNA/FNB. The primary outcomes were diagnostic accuracy and sensitivity, and these were stratified based on several intraprocedural factors including tumor size and number of passes. Samples with pathology reports of atypia without confirmed malignancy were considered non-malignant. RESULTS: Of 204 patients who underwent EUS with FNA/FNB, 38 were done for solid pancreatic masses. 166 patients were excluded due to cystic lesions (49) and 117 were done for intramural lesions or EUS-liver biopsy. For solid masses, the mean maximum tumor diameter was 26.9mm, with 46% occurring in the head or uncinate process (Table 2). The mean number of passes was 2.39 and 87% were done with a 22-gauge needle. On-site cytopathology was present for 37% of cases and 21% were done with general anesthesia. 53% had a duodenal approach. The overall diagnostic rate was 95%. Sensitivity for pancreatic malignancy was 85% and specificity was 100%. Sensitivity and diagnostic rates are higher with increasing tumor size, 2-4 needle passes vs 2-3 passes, and for masses in the pancreatic tail vs neck (Table 2). CONCLUSION: he diagnostic accuracy and sensitivity of EUS-FNA/FNB for solid pancreatic lesions were 95% and 85%, respectively, at our institution, thus meeting the ASGE grade 1C guidelines, despite fewer passes and less on-site cytopathology presence compared with larger studies[2].Table 1.: Demographics of patients with solid pancreatic tumorsTable 2.: Subgroup analysis by needle size, number of passes, tumor stage and approach (trans-gastric vs. trans-duodenum)

Sa1459 COMPLIANCE WITH ASGE QUALITY INDICATORS FOR ENDOSCOPIC ULTRASOUND REPORTS IN THE EVALUATION OF PANCREATIC CANCER, COMPARISON OF COMMUNITY AND ACADEMIC PRACTICES

The American Society for Gastrointestinal Endoscopy (ASGE) has put forth a list of quality indicators for EUS which evaluate key steps that provide endoscopists targets to provide high quality care. Endoscopist compliance with the ASGE quality indicators has not been well studied in patients who have undergone EUS and subsequent resection for pancreatic cancer. The goal of this study is to evaluate the quality of EUS performed for pancreatic cancer diagnosis and staging in patients who had initial EUS performed at our institution or who had initial EUS performed at an outside institution and were referred to our institution and have subsequently undergone pancreatic cancer resection. Consecutive patients who had EUS for suspected pancreatic cancer and who had subsequently undergone Whipple at a single tertiary care center between 2013 and 2019 were identified by searching an IRB approved surgical database of patients with resected pancreatic cancer. Patients with incomplete documentation were excluded. Patient demographics, pancreatic lesion characteristics, surgical pathology and operative reports, as well as EUS report data were recorded. Comparative analysis of patients who had EUS performed at a single academic medical center (AMC) and referring institutions (OSH) was performed. 203 patients underwent surgical resection for pancreatic cancer between 2013-2019 and had an EUS report available for review. The mean patient age was 65.4±0.64* years, mean BMI 27.3±0.39, and 95 (46.8%) were female. EUS-FNA/B (fine needle aspiration/biopsy) revealed malignancy in 85.7% cases at the AMC and 80.4% at OSH (p=0.35). Significant differences between the AMC and OSH EUS reports were noted in terms of compliance with ASGE quality indicators. Specifically, the total number of ASGE quality indicators (6.6±0.1 vs 5.6±0.2, p= <0.001) included in the report, listing of an ASGE approved indication for EUS (99.3% vs 89.3%, p=0.002), use on an on-site cytopathologist (69.9% vs 51.8%, p= 0.02), TNM classification (56.3% vs 23.2%, p= <0.001) inclusion, and documentation of the presence or absence of an intraprocedural complication (100% vs 83.9%, p= <0.001) were significantly higher in the AMC EUS reports (Table 1). AMC EUS reports were more likely to describe the biliary tree (97.3% vs 67.9%, p= <0.001) though were less likely to describe the pancreatic duct (74.1% vs 89.3%, p=0.02). No other factors were statistically significant (Table 1). In our cohort of patients with resected pancreatic cancer who had previously undergone EUS, the quality of EUS reports from an AMC were superior to OSH EUS reports based on ASGE quality indicators for EUS. However, this did not translate into a statistically significant increase in the diagnostic yield of EUS-FNA/B. Further evaluation with a larger patient population will likely be beneficial.

Sa1450 YIELD OF PANCREATIC FINE-NEEDLE BIOPSY NOT AFFECTED BY PRIOR BILIARY STENT PLACEMENT

Endoscopic ultrasound for suspected malignant pancreatic lesions is useful for confirmation of diagnosis, identifying medically treatable disease, accurate staging and may improve survival for those undergoing surgery. Traditionally, EUS is performed prior to ERCP for those requiring biliary drainage over concern that stenting may affect staging or biopsy yield secondary to inflammation or sonographic distortion. To date studies have been conflicting on whether pre-operative stenting affects biopsy yield. All pancreatic fine needle biopsies performed at our center over the last 7 years (October 2012 - October 2019) were identified by searching the pathology laboratory electronic medical record for the specimen types 'pancreas fine needle biopsy'. Clinical chart review was undertaken and age, sex, location of lesion, size of lesion, final pathologic diagnosis, date and time of biopsy and date and time of biliary stenting, if any was recorded. On-site cytopathology is not used in EUS guided biopsy at our center. Biopsy interpretation was taken from the final pathology report and classified as either diagnostic or non-diagnostic. Two tailed P-value for difference in rate of diagnostic biopsy was performed using Fisher’s exact test. Confidence interval of diagnostic yield was calculated using the modified Wald method. 233 individual results were identified. 9 duplicates were excluded. 54% were male. Mean age was 65. A definitive diagnosis was made in 184 biopsies, 40 biopsies were non-diagnostic. 131 samples were classified as pancreatic head, uncinate process or neck masses. 85 were classified as pancreatic body or tail with 8 from either an atypical site or unreported site. 61 biopsies were performed with a stent in-situ. Diagnostic yield for biopsies on unstented patients was 0.82 (95% CI 0.75-0.87) versus 0.84 (95% CI 0.72-0.91) for biopsies on patients with biliary stents in-situ. This difference was not statistically significant (p=0.8455). Post-hoc power calculations suggest greater than 80% likelihood of identifying a significant difference with the current sample size. Similar analyses were performed using only pancreatic head lesions with a similar result though the test was underpowered to detect a significant difference. In the absence of medical or logistical reasons, EUS guided biopsy prior to biliary stenting should be considered as pathologic diagnosis may affect therapeutic decisions. However, our analysis suggests that in situations when biliary stenting prior to biopsy is indicated or if prior EUS is impractical, clinicians can be reassured that future biopsy yield will likely not be affected.

Su1299 COMPARISON OF THE PERFORMANCE OF 2 CORE BIOPSY NEEDLES FOR ENDOSCOPIC ULTRASOUND-GUIDED LIVER BIOPSY

Endoscopic ultrasound-guided fine needle biopsy of the liver (EUS-LB) is a safe and effective technique to assess liver histology. EUS-LB is commonly performed using a 19-gauge fine needle biopsy (FNB). Two popular models used for EUS-LB differ in tip geometry. One has a 3-planed, Franseen-style tip with symmetric cutting surfaces (Acquire; Boston Scientific; Marlborough, MA). The other has a 2-pronged, fork-tip with asymmetric cutting surfaces (SharkCore; Medtronic; Sunnyvale, CA). Herein, we compare these two needles with respect to safety and tissue yield in EUS-LB. This is a retrospective analysis of all patients referred for EUS-LB between January 2017 and May 2019. All EUS-LB were performed using 19G Franseen or fork-tip needles, but the specific model selection, biopsy location, and number of passes were at endoscopist’s discretion. EUS-LB was performed via one pass, one actuation, wet suction technique without on-site cytopathology. All endoscopists grossly evaluated the specimen procured from each pass to determine whether another pass was needed. One hundred sixteen patients underwent EUS-LB. Franseen and fork-tip needles were employed in 71 and 89 cases respectively. Baseline patient characteristics were similar between the cohorts. Overall, both needles yielded comparable results with respect to aggregate length (29.5 vs 27mm, p=0.39), longest intact core (16.7 vs 19.8mm, p=0.10) and complete portal tracts (18.1 vs 16.9, p=0.47). However, more passes were performed with fork-tip (146) compared to Franseen needles (100), with a mean of 1.64 vs 1.41 (p=0.02). When only single pass biopsies were examined (46 Franseen, 39 fork-tip), the Franseen needle yielded statistically greater aggregate length (34.4 vs 27.1mm, p=0.05) and longest intact core (23.1 vs 17.5mm, p=0.01). Four EUS-LB procedures (2.5%) resulted in samples that were inadequate for histologic diagnosis (Franseen-1.4%, fork-tip-3.4%; p=NS). Adverse events after EUS-LB consisted of two cases of post-procedural bleeding (1.3%) not requiring intervention; one after Franseen (1.4%) and one after fork-tip FNB (1.1%; p=NS). Both Franseen and fork-tip fine needle biopsy needles appear safe and effective for endoscopic ultrasound-guided liver biopsy. However, fewer passes are needed and more tissue is procured in a single pass when using the Franseen model.Figure 1Comparison of results of endoscopic ultrasound-guided liver biopsy using the Franseen and Fork-tip needle systems between all samples (above) and single-pass only samples (below). Metrics examined were aggregate length (mm), longest intact core (mm) and complete portal tracts.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Concordancia entre la tomografía axial computarizada de abdomen, la ultrasonografía endoscópica y la punción por aspiración con aguja fina en el diagnóstico de lesiones sólidas sugestivas de neoplasias malignas de páncreas

Introducción y objetivo: la realización de pruebas para el diagnóstico de lesiones sólidas de páncreas conduce frecuentemente a resultados discordantes, lo que genera confusión y retraso en las decisiones terapéuticas. La concordancia entre los resultados de la tomografía axial computarizada de abdomen con contraste (TAC), la ultrasonografía endoscópica (USE) biliopancreática y la punción por aspiración con aguja fina guiada por ultrasonografía endoscópica (PAAF-USE) no ha sido evaluada en nuestro medio.&#x0D; Materiales y métodos: se evaluó una serie de pacientes adultos con masas sólidas del páncreas sospechosas de malignidad, atendidos en el Hospital Universitario San Ignacio (HUSI) de Bogotá (Colombia), en los cuales se realizaron, por lo menos, dos de las siguientes pruebas: TAC, USE o PAAF-USE. Se evaluó la concordancia de los resultados, definidos como compatibles con neoplasia, no compatibles con neoplasia o resultado no conclusivo.&#x0D; Resultados: se incluyeron 57 pacientes. Un alto porcentaje de estos, con USE compatible con neoplasia, tuvieron resultados discordantes con la TAC (33,3 %) y con la PAAF-USE (52,5 %). La concordancia entre imágenes y PAAF-USE fue mínima (kappa = 0,02; intervalo de confianza [IC] 95 %, 0,04-0,08). La probabilidad de detectar un compromiso vascular fue significativamente mayor en la USE (42,1 % frente a 23,8 %, p = 0,06) a diferencia del compromiso ganglionar, que fue detectado más frecuentemente por imágenes (TAC/resonancia magnética nuclear [RMN]) (23,8 % frente a 7,1 %, p = 0,01).&#x0D; Conclusiones: los resultados de este estudio sugieren un pobre acuerdo entre los diferentes métodos diagnósticos y advierten que es necesario implementar mejoras como la elastografía y medios de contraste, nuevas modalidades de aguja para la toma de muestras o la presencia de un citopatólogo in situ.