Multicenter prospective study of the efficacy of stereomicroscopic on-site evaluation in endoscopic ultrasound-guided tissue acquisition in patients with pancreatic cancer.

OBJECTIVE: In sample isolation processing by stereomicroscopy (SIPS), a technique used to assess the quality of specimens collected during endoscopic ultrasound (EUS)-guided tissue acquisition (EUS-TA), the cutoff value of stereomicroscopically visible white core (SVWC) (≥11 mm) indicates high diagnostic sensitivity. However, the procedure of SIPS is complicated and time-consuming. Therefore, we devised the stereomicroscopic on-site evaluation (SOSE), a new rapid assessment method that is simpler than SIPS and only determines if the SVWC cutoff value is attained. We aimed to examine the usefulness of SOSE in a multicenter, prospective setting. METHODS: Seventy patients from multiple institutions with solid pancreatic masses suspected to be pancreatic cancer were included. EUS-TA was performed using a 22-gauge Franseen needle. SVWCs were measured on-site using stereomicroscopy. The primary outcome was the sensitivity of SVWC cutoff value in EUS-TA with SOSE. RESULTS: The total number of punctures was 214 and SOSE was performed on 150 punctures. The SVWC cutoff value collection rate was 100% per lesion, with 80% in the first pass, 79% in the second pass, and 78% per puncture in all passes. The median time taken to determine the SVWC cutoff value for SOSE was 47 s. The sensitivity of the SVWC cutoff value was 93.2% for histology and 96.6% for cytology + histology. The per-lesion accuracy of pathological diagnosis reached the highest level (98.6%) at the second puncture. CONCLUSIONS: SOSE showed high diagnostic sensitivity and may be a new rapid assessment method for the diagnosis of malignant pancreatic cancer using EUS-TA.

Endoscopic re-intervention after stent-in-stent versus side-by-side bilateral self-expandable metallic stent deployment.

BACKGROUND AND AIM: Endoscopic bilateral self-expandable metallic stent (SEMS) placement for unresectable malignant hilar biliary obstruction (MHBO) is widely performed; however, re-intervention after recurrent biliary obstruction (RBO) is often challenging. We compared stent-in-stent (SIS) and side-by-side (SBS) SEMS placement for MHBO considering re-intervention for RBO. METHODS: One hundred five consecutive patients with MHBO who underwent endoscopic bilateral SEMS placement in our hospital and its affiliated institutions were enrolled in this study; 75 patients underwent partial SIS deployment between December 2005 and December 2012; and 30 underwent SBS deployment between January 2013 and March 2019. Initial treatments and re-interventions in each group were retrospectively evaluated. RESULTS: Technical success rate (92% vs 100%, P = 0.179), procedure duration (46 vs 35 min, P = 0.382), functional success rate (97.1% vs 100%, P = 1.00), complication rate (24.6% vs 20.0%, P = 0.797), time to RBO (260 vs 312 days; Gray test, P = 0.815), and rate of RBO (59.4% vs 70.0%, P = 0.371) were not significantly different between the SIS and SBS groups. However, bilateral re-stenting with plastic stents through SEMS was successful in 63.4% of patients in the SIS group compared with 100% of patients in the SBS group (P = 0.0013). Median time to RBO upon first re-stenting with a plastic stent was 75 days (range, 11-195 days). CONCLUSIONS: Endoscopic re-stenting after RBO was significantly more successful in the SBS group than in the SIS group. SBS method is suitable for MHBO considering revisionary stent placement.

Nafamostat Mesylate is Not Effective in Preventing Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis.

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) is associated with complications such as post-ERCP pancreatitis (PEP). Protease inhibitors, including nafamostat mesylate (NM), have been evaluated for prophylaxis against PEP. AIM: We describe the first multicenter randomized controlled trial assessing the prophylactic efficacy of NM against PEP. METHODS: In this multicenter prospective study, we aimed to enroll 800 patients aged ≥ 20 years with a planned ERCP between December 2012 and March 2019. The primary outcome was the incidence and severity of PEP in patients who did not receive NM (non-NM) versus those who did (NM; 20 mg). Secondary outcomes included the incidence of PEP by NM initiation (pre- and post-ERCP), risk factors for PEP, and NM-related adverse events. RESULTS: Only 441 of the planned 800 patients were enrolled (non-NM: n = 149; NM: n = 292 [pre-ERCP NM: n = 144; post-ERCP NM: n = 148]). Patient characteristics were balanced at baseline with no significant differences between groups. PEP occurred in 40/441 (9%) patients (non-NM: n = 15 [10%]; NM: n = 25 [9%]), including 17 (12%) and eight (8%) in the pre-ERCP and post-ERCP NM groups, respectively. In the NM group, the incidence of PEP was lower in the low-risk group than in the high-risk group. Pancreatic injection and double-guidewire technique were independent risk factors for PEP. NM-related adverse events of hyperkalemia occurred in two (0.7%) patients. CONCLUSIONS: We found no evidence for the prophylactic effect of NM against PEP, regardless of the timing of administration; however, further studies are needed.

On-site stereomicroscope quality evaluations to estimate white core cutoff lengths using EUS-FNA biopsy sampling with 22-gauge needles.

BACKGROUND AND AIMS: Although rapid on-site cytologic evaluation (ROSE) during EUS-guided FNA biopsy (EUS-FNAB) sampling may improve accuracy of pathologic analyses, cytopathologists are not widely available. We calculated the cutoff lengths required for accurate pathologic diagnoses from stereomicroscopically visible white cores (SVWCs) sampled using 22-gauge needles. METHODS: Overall, 118 patients with mediastinal or upper abdominal solid masses requiring pathologic diagnoses were included. EUS-FNAB sampling was performed using 22-gauge needles. SVWCs were isolated and measured using stereomicroscopy, and the utility of calculated cutoff lengths in diagnosis was investigated. RESULTS: The procedure success and SVWC sampling rates were both 100%, and the median SVWC length was 10 mm. Pathologic examination identified 75, 31, and 12 patients with pancreatic neoplasms (PNs), subepithelial lesions (SELs), and other lesions, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for diagnosing malignancy using EUS-FNAB sampling were 93.1%, 100%, 100%, 69.6%, and 94%, respectively. The final diagnostic accuracy in the entire cohort, PNs, and SELs was 92.4%, 90.7%, and 93.5%, respectively. Receiver operating characteristic curves demonstrated the overall SVWC cutoff length to be 11 mm (11 mm for PNs, 3.5 mm for SELs). The overall sensitivity according to SVWC cutoff length was 91.4% (87.6% for PNs, 98.8% for SELs). Compared with cutoff length, multivariate analysis confirmed SVWC length to be a stronger independent factor for tissue diagnosis in both groups. CONCLUSIONS: Diagnosis improved significantly with SVWC cutoff lengths ≥11 mm. This may be a useful index for endoscopists, particularly where ROSE is unavailable. (Clinical trial registration number: UMIN000023013.).

Transpapillary Biliary Cannulation is Difficult in Cases with Large Oral Protrusion of the Duodenal Papilla.

BACKGROUND: Biliary cannulation failure is a major problem during endoscopic retrograde cholangiopancreatography. It remains unclear how duodenal papilla morphology affects biliary cannulation. Therefore, we proposed a new classification system for the duodenal papilla based on oral protrusion pattern (ratio of the length of the oral protrusion to the transverse diameter of the papilla) and papilla pattern. AIMS: To retrospectively compare biliary cannulation results with regard to classification and operator experience. METHODS: We analyzed 589 naïve major duodenal papillae. Our classification system comprised oral protrusion pattern, classified as small (Protrusion-S), regular (Protrusion-R), or large (Protrusion-L), and the papilla pattern, classified as annular (Papilla-A), unstructured (Papilla-U), longitudinal (Papilla-LO), isolated (Papilla-I), or gyrus (Papilla-G). Intra-evaluator concordance and the results of biliary cannulation were analyzed. RESULTS: The following oral protrusion pattern classifications were observed: Protrusion-S, 11.7%; Protrusion-R, 77.9%; and Protrusion-L, 10.4%. The following papilla patterns were observed: Papilla-A, 67.1%; Papilla-U, 7.0%; Papilla-LO, 7.5%; Papilla-I, 1.2%; Papilla-G, 15.6%; and unclassified, 1.7%. Intra-evaluator concordance value (Fleiss kappa) was 0.788 for oral protrusion pattern and 0.750 for papilla pattern. A logistic regression analysis of cannulations performed by an experienced endoscopist identified Protrusion-L as a significant risk factor for difficult cannulation (odds ratio 2.956; 95% confidence interval 1.115-7.84; p = 0.029). Multivariate analysis confirmed Protrusion-L as an independent risk factor for difficult biliary cannulation (odds ratio 3.772; 95% confidence interval 1.359-10.464; p = 0.011). CONCLUSIONS: We propose a new general classification system for the duodenal papilla. Protrusion-L is a significant risk factor for difficult biliary duct cannulation.

A clinical trial to assess the feasibility and efficacy of nab-paclitaxel plus gemcitabine for elderly patients with unresectable advanced pancreatic cancer.

BACKGROUND: The efficacy and safety of nanoparticle albumin-bound paclitaxel (nab-PTX) plus gemcitabine (GEM) in elderly Japanese patients with pancreatic cancer remain unclear. Therefore, we prospectively investigated the tolerability and efficacy of nab-PTX + GEM in Japanese patients aged ≥ 75 years with non-curatively resectable pancreatic cancer. METHODS: We treated eligible patients (n = 27) with nab-PTX + GEM until disease progression, appearance of adverse events, or withdrawal of consent. The primary endpoints included adverse events as well as dosing- and survival-related parameters. RESULTS: The rates of 2-cycle completion were 48.1% for nab-PTX and 55.6% for GEM; the relative dose intensities for the 7th (median) treatment cycle were 65.1% and 74.1%, respectively, whereas the dose-reduction rates were 81.5% and 48.1%, respectively. Grade 3 or higher hemotoxicity was observed in 14 of 27 subjects (51.9%); moreover, 22% experienced grade ≥ 3 peripheral nerve disorder and 1 patient (3.7%) died owing to chemotherapy-related interstitial pneumonia. The disease control rate was 92.6% (25/27), while the median progression-free and overall survival times were 7 and 10.3 months, respectively. CONCLUSION: The nab-PTX + GEM regimen is as efficacious in elderly patients who meet certain criteria as it is in previously reported non-elderly patients. The regimen is feasible with appropriate dose adjustments and attention to adverse events. TRIAL REGISTRATION: Clinical trial registration number: UMIN000018907.

Therapeutic peroral direct cholangioscopy using a single balloon enteroscope in patients with Roux-en-Y anastomosis (with videos).

BACKGROUND: Peroral cholangioscopic lithotripsy is a useful procedure in patients with a normal gastrointestinal anatomy who have difficult-to-treat stones. We evaluated the usefulness of peroral direct cholangioscopy (PDCS) using single-balloon enteroscope (SBE) in patients with difficult-to-treat stones who had undergone Roux-en-Y reconstruction. METHODS: Among 118 patients (169 sessions) who underwent SBE-assisted endoscopic retrograde cholangiopancreatography to treat biliary stones after Roux-en-Y reconstruction, patients in whom it was difficult to remove biliary stones via a transpapillary or transanastomotic approach and difficult to switch to ultra-slim endoscope, were retrospectively enrolled. The biliary insertion success rate, procedure success rate, procedure time, and procedural complications were assessed. The SBE was inserted into the bile-duct, first using a free-hand technique, second using a guide wire, and third using the large balloon anchoring and deflation (LBAD) technique. RESULTS: A total of 11 patients (14 sessions) were enrolled in this study. The biliary insertion success rate was 100%. Bile-duct insertion was performed using a free-hand technique in 4 sessions, a guide wire in 3 sessions (rendezvous technique, 2 sessions), and the LBAD technique in 7 sessions. The procedure success rate was 86% in first session, and 100% in second session. The median procedure time was 81 min (range 49-137). The median procedure time in the bile-duct was 21.5 min (range 6-60). Mild pancreatitis occurred as a complication in one patient. The median follow-up was 528 days (range 282-764). No patient had stone recurrence. CONCLUSIONS: PDCS using SBE is a useful procedure in patients with Roux-en-Y reconstruction. The LBAD technique is an useful technique of inserting SBE into the bile-duct.

Analysis of the diagnostic yield of endoscopic ultrasonography-guided fine-needle aspiration in patients with a suspected pancreatic malignancy.

OBJECTIVES: to determine the diagnostic yield of endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) for suspected pancreatic malignancy. As well as to identify factors that affect the incidence of false-negative cases and evaluate the value of repeated EUS-FNA in patients with inconclusive results. METHODS: we retrospectively evaluated the data of patients who underwent EUS-FNA due to a suspected pancreatic malignancy in our hospital from January 2015 to December 2016. RESULTS: a total of 194 EUS-FNA procedures performed and 175 cases were analyzed. The overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were 83.4% (151/181), 100% (13/13), 100% (151/151), 30.2% (13/43), and 84.5% (164/194), respectively. The combination of cytological and histological examination significantly increased the diagnostic performance compared to either method alone. The diagnostic sensitivity in metastatic tumors was significantly lower than that for adenocarcinoma. EUS-FNA performed using standard needles combined with the "slow-pull" technique had a lower sensitivity than other methods. According to the multivariate analysis, neither the combination of needle type and suction technique nor final diagnosis were independent factors that affected the diagnostic sensitivity. The sensitivity of repeated EUS-FNA was 50.0% (8/16). Definitive results after a repeated puncture were more likely for pancreatic body and tail masses, heterogeneous lesions and poorly demarcated lesions. However, the difference was not significant. CONCLUSIONS: EUS-FNA was accurate for the evaluation of a suspected pancreatic malignancy. Metastatic tumors and the use of a standard needle in combination with the slow-pull technique may increase the incidence of false-negative results. Repeated EUS-FNA has limited value but should be considered for selected cases where the suspicion of malignancy persists.

Endoscopic ultrasonography diagnosis of subepithelial lesions.

Using endoscopic ultrasonography (EUS), it is practicable to diagnose subepithelial lesions (SEL) with originating layer, echo level, and internal echo pattern etc. Lipoma, lymphangioma, and cyst have characteristic features; therefore, there is no need for endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). Ectopic pancreas and glomus tumors, which originate from the third and fourth layers, are frequently seen in the antrum. However, ectopic pancreas located in the fundus or body is large and originates from the third and fourth layers (thickening of fourth layer). Each subepithelial lesion has characteristic findings. However, imaging differentiation of tumors originating from the fourth layer is very difficult, even if contrast echo is used. Therefore, EUS-FNA should be done in these tumors, but the diagnostic yield for small lesions is not sufficient for clinical demands. Generally, those tumors, including small ones, should be first followed up in 6 months, then yearly follow up in cases of no significant change in size and features. When those tumors become larger than 1-2 cm, EUS-FNA is recommended. Furthermore, unusual SEL and SEL with malignant findings such as nodular, heterogeneous, anechoic area, and ulceration indicate EUS-FNA. Cap-attached forward-viewing echoendoscope is very helpful for EUS-FNA of small SEL.

A Case Series: Outcomes of Endoscopic Biliary Self-Expandable Metal Stent for Malignant Biliary Obstruction with Surgically Altered Anatomy.

BACKGROUND: Few studies have reported the outcomes of self-expandable metal stent (SEMS) placement for malignant biliary obstruction in patients with surgically altered anatomy. AIMS: To evaluate the outcomes of biliary metal stent placement with the use of a short-type single-balloon enteroscope (working length, 1520 mm; channel diameter, 3.2 mm) in such patients. METHODS: We retrospectively studied 13 malignant biliary obstructions treated by SEMS placement. Technical success rate, functional success rate, time to recurrent biliary obstruction (RBO), and complications were evaluated. RESULTS: Technical success rate was 100 % (13/13), functional success rate was 92 % (12/13), and the median time to RBO was 247 days (95 % CI 205.6-285.5). Complications comprised mild pancreatitis in one patient. Uncovered SEMSs were placed in three obstructions, partially covered SEMS in five obstructions, and fully covered SEMSs in five obstructions. Three stents occluded (two ingrowths and one mucosal hyperplasia), and one symptomatic distal stent migration occurred after more than 30 days from placement. CONCLUSIONS: A short-type single-balloon enteroscope was useful for the placement of various SEMS in this patient population with satisfactory outcomes.

Stereomicroscopic on-site evaluation in endoscopic ultrasound-guided tissue acquisition of upper gastrointestinal subepithelial lesions.

BACKGROUND/AIMS: In stereomicroscopic sample isolation processing, the cutoff value (≥4 mm) of stereomicroscopically visible white cores indicates high diagnostic sensitivity. We aimed to evaluate endoscopic ultrasound-guided tissue acquisition (EUS-TA) using a simplified stereomicroscopic on-site evaluation of upper gastrointestinal subepithelial lesions (SELs). METHODS: In this multicenter prospective trial, we performed EUS-TA using a 22-gauge Franseen needle in 34 participants with SELs derived from the upper gastrointestinal muscularis propria, requiring pathological diagnosis. The presence of stereomicroscopically visible white core (SVWC) in each specimen was assessed using stereomicroscopic on-site evaluation. The primary outcome was EUS-TA's diagnostic sensitivity with stereomicroscopic on-site evaluation based on the SVWC cutoff value (≥4 mm) for malignant upper gastrointestinal SELs. RESULTS: The total number of punctures was 68; 61 specimens (89.7%) contained stereomicroscopically visible white cores ≥4 mm in size. The final diagnoses were gastrointestinal stromal tumor, leiomyoma, and schwannoma in 76.5%, 14.7%, and 8.8% of the cases, respectively. The sensitivity of EUS-TA with stereomicroscopic on-site evaluation based on the SVWC cutoff value for malignant SELs was 100%. The per-lesion accuracy of histological diagnosis reached the highest level (100%) at the second puncture. CONCLUSION: Stereomicroscopic on-site evaluation showed high diagnostic sensitivity and could be a new method for diagnosing upper gastrointestinal SELs using EUS-TA.

Effectiveness of endoscopic ultrasound-guided tissue acquisition with stereomicroscopic on-site evaluation for preoperative diagnosis of resectable or borderline resectable pancreatic cancer: a prospective study.

Background/Aims: To validate endoscopic ultrasound-guided tissue acquisition (EUS-TA) used in conjunction with stereomicroscopic on-site evaluation (SOSE) as a preoperative diagnostic tool for resectable pancreatic cancer (R-PC) and borderline resectable PC (BR-PC). Methods: Seventy-eight consecutive patients who underwent EUS-TA for suspected R-PC or BR-PC were enrolled. The primary endpoint was the sensitivity of EUS-TA together with SOSE based on the stereomicroscopically visible white core (SVWC) cutoff value. One or two sites were punctured by using a 22-gauge biopsy needle for EUS-TA, based on the SOSE findings. Results: We collected 99 specimens from 56 and 22 patients with R-PC and BR-PC, respectively. Based on the SOSE results, we performed 57 procedures with one puncture. The SVWC cutoff values were met in 73.7% and 73.1% of all specimens and in those obtained during the first puncture, respectively. The final diagnoses were malignant and benign tumors in 76 and two patients, respectively. The overall sensitivity, specificity, and accuracy of EUS-TA for the 78 lesions were 90.8%, 100%, and 91.0%, respectively. The sensitivity for malignant diagnosis based on the SVWC cutoff value were 89.5% and 90.4% for the first puncture and all specimens, respectively. Conclusions: The sensitivity of EUS-TA in conjunction with SOSE for malignancy diagnosis in patients with suspected R-PC or BR-PC was 90.4%.

Implication of Skeletal Muscle Loss in the Prognosis of Patients with Pancreatic Ductal Adenocarcinoma Receiving Chemotherapy.

Objective The effect of sarcopenia on the prognosis of patients undergoing chemotherapy for unresectable pancreatic ductal adenocarcinoma remains largely unexplored. In this retrospective study, we investigated the relationship between sarcopenia and the prognosis of patients receiving first-line nanoparticle albumin-bound paclitaxel plus gemcitabine for unresectable pancreatic ductal adenocarcinoma. Methods We enrolled 251 patients with unresectable metastatic or locally advanced pancreatic ductal adenocarcinoma who had received chemotherapy between January 2015 and December 2020 at Kitasato University Hospital. Univariate and multivariate analyses were performed using the stratified Cox proportional hazards model to determine variables significantly associated with the progression-free and overall survival. Propensity score matching was performed to mitigate selection bias effects. Results In the propensity score-matched cohort, the progression-free and overall survival were not significantly different between the sarcopenia and non-sarcopenia groups (p=0.335, and 0.679 respectively). The skeletal muscle index decreased by 4.4% and 6.5% in the sarcopenia and non-sarcopenia groups, respectively, during the early treatment phase (p=0.084). There were no significant differences between groups with regard to major adverse events or drug toxicity occurrences. Both the progression-free and overall survival were significantly shorter in the skeletal muscle index loss group than in the non-skeletal muscle index loss group (p=0.026 and 0.045, respectively). Conclusion Skeletal muscle index loss during the initial treatment phase may be an early marker for the long-term prognosis of patients receiving nanoparticle albumin-bound paclitaxel plus gemcitabine as first-line treatment for unresectable pancreatic ductal adenocarcinoma.

Pancreatic Cancer Cells May Adhere to the External Surface of the Puncture Needle After Endoscopic Ultrasound-Guided Fine-Needle Aspiration.

OBJECTIVE: We prospectively investigated whether cells derived from pancreatic cancers adhered to the puncture needle's external surface after endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and whether wiping the needle with alcohol swabs removed residual cancer cells. METHODS: The participants were 100 consecutive patients who underwent EUS-FNA for suspected pancreatic ductal adenocarcinoma. In the first pass of EUS-FNA, we prepared aspiration and lavage cytological diagnosis materials from the lumen and external surface of the puncture needle, respectively. This was repeated in the second pass, although the needle's external surface was wiped with an alcohol swab. RESULTS: The positivity rates of aspiration cytological diagnosis for the first and second passes were 67% and 72%, respectively. The positivity rates of lavage cytological diagnosis of the needle's external surface on the first and second passes were 20% and 3%, respectively. Wiping the needle's external surface with alcohol swabs significantly reduced the proportion of cancer cells detected ( P < 0.001). The accuracy rate based on all the collected specimens was 90%. There were no EUS-FNA-related adverse events. CONCLUSION: Pancreatic cancer cells may adhere to the puncture needle's external surface after EUS-FNA. Wiping the needle with alcohol swabs after each puncture effectively removes residual cancer cells.

New image-processing technology for endoscopic ultrasound-guided fine-needle aspiration biopsy specimen evaluation in patients with pancreatic cancer.

Objectives: We evaluated the usefulness of a newly developed system with which the total amount of whitish cores in endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) samples is automatically calculated (automated multiband imaging system [AMUS]). Methods: From 30 prospectively enrolled patients suspected of having pancreatic cancer, four EUS-FNAB specimens per patient were obtained. Following AMUS calculations, two specimens were prepared after stereomicroscopy-guided manual division into whitish and reddish sections (isolation group), and the other two were prepared without such division (no-isolation group). The relation of the AMUS results pertaining to the length of the manually measured whitish cores (stereo-microscopically visible white core [SVWC]) and the sample suitability for pathologic evaluation were analyzed. Results: Histological diagnostic accuracy was 90%; median SVWC length, 14 mm; and median area of whitish core calculated using the AMUS, 13 mm2. The SVWC length correlated with whitish core amount (ρ = 0.83, p < 0.01) and adequacy score (ρ = 0.50, p < 0.01). The whitish core amount correlated with the adequacy score (ρ = 0.40, p < 0.01). The area under the receiver-operating characteristic curve calculated for whitish core amount with respect to the histological diagnosis was 0.84 (p < 0.01; cutoff ≥ 8 mm2, sensitivity 92.5%). Subgroup analysis (isolation vs. no-isolation group) revealed no significant between-group differences in the median histological adequacy (p = 0.27) or tumor cell content ratio (p = 0.28). The median scores for degree of blood contamination were significantly lower in the isolation group than in the no-isolation group (p < 0.01). Conclusion: AMUS is a simple on-site verification procedure for determining the appropriate sampling tissue quantity for high diagnostic accuracy.

Usefulness of the automated multiband imaging system for EUS-FNA biopsy specimen evaluation in patients with upper gastrointestinal subepithelial lesions.

Background and Objectives: Sample isolation processing by stereomicroscopy (SIPS) was recently introduced as an alternative to rapid on-site cytologic evaluation and showed high accuracy for use in pathologic diagnoses. SIPS is a useful, but slightly complicated procedure; therefore, a new, more straightforward method for the objective estimation of the core tissue amount required during the sampling is desirable. We evaluated the usefulness of the automated multiband imaging system (AMUS) for calculating whitish core amounts in EUS-FNA biopsy (EUS-FNAB) samples from patients with subepithelial lesions (SELs). Methods: Four EUS-FNAB specimens per patient were obtained from 20 patients with upper gastrointestinal SELs. The correlation between the whitish core amount calculated by AMUS, length of the manually measured whitish cores (stereomicroscopically visible white core [SVWC]), and sample suitability for pathologic evaluation were analyzed. Results: We identified 13 patients with gastrointestinal stromal tumors, five with leiomyomas, one with a schwannoma, and one with an ectopic pancreas. The histological diagnostic accuracy was 100%, median SVWC length was 9 mm, and median whitish core area, calculated using AMUS, was 10 mm2. SVWC length correlated with whitish core amount (ρ = 0.81, P < 0.01) and adequacy score (ρ = 0.54, P < 0.01). Whitish core amount correlated with adequacy score (ρ = 0.54, P < 0.01). The area under the receiver-operating characteristic curve calculated for whitish core amount with respect to the histological diagnosis was 0.83 (P < 0.01; cutoff ≥4 mm2, sensitivity 98.4%). Conclusions: AMUS, a simple on-site verification instrument, is an alternative to SIPS for determining the appropriate SEL tissue sampling quantity with high diagnostic accuracy.

EUS-guided transanastomotic drainage for severe biliopancreatic anastomotic stricture using a forward-viewing echoendoscope in patients with surgically altered anatomy.

BACKGROUND AND OBJECTIVES: Balloon enteroscopy-assisted ERCP (BE-ERCP) has become the first-line therapy for biliopancreatic anastomotic strictures. However, it is not always successful, and salvage methods have not been established. This study aimed to evaluate the outcomes of EUS-guided transanastomotic drainage using a forward-viewing (FV) echoendoscope. PATIENTS AND METHODS: Of eight cases wherein BE-ERCP treatment failed due to severe or complete benign anastomotic stricture, seven cases underwent EUS-guided choledochojejunostomy, and EUS-guided pancreaticojejunostomy was applied in one case after intubating an FV echoendoscope into the anastomotic site. RESULTS: The success rate of reaching the target site was 100% (8/8) for patients after modified Child resection. The median time to reach the anastomosis was 5 min (range: 3-17 min), and the technical success rate for drainage was 75% (6/8). The median total procedure time was 33.5 min (range: 22-45 min) for six successful cases. Cautery dilatation catheters were necessary to dilate the puncture site in all cases, and no early complications were observed. During the follow-up period (median: 13.3 months [range: 6.5-60.3]), recurrence of the stricture occurred in one case, and a stent-free status was achieved after 6-12 months of stent placement in five cases. CONCLUSIONS: EUS-guided transanastomotic drainage using an FV echoendoscope is a feasible and safe rescue technique for the management of benign severe biliopancreatic anastomotic strictures.

A case of pancreatic neuroendocrine carcinoma with a favorable clinical response to pembrolizumab.

A 76-year-old man with epigastric pain developed 1 month earlier was referred to our department for additional screening and treatment after abdominal ultrasound revealed a mass shadow in the pancreatic head and liver. Blood biochemistry revealed signs of mild jaundice and hepatic dysfunction. Abdominal contrast-computed tomography revealed an irregular hypodense mass with poor enhancement in the pancreatic head and several hypodense nodules in the liver. Endoscopic examination revealed duodenal infiltration signs. The biopsied duodenal mucosa contained atypical cells with high nuclear-to-cytoplasmic ratios; the cells stained positive for CD56, chromogranin, and synaptophysin, and the Ki-67 index was 90%. Accordingly, pancreatic neuroendocrine carcinoma (PanNEC) was diagnosed. Platinum-based chemotherapy (6 courses) and streptozotocin (10 courses) were adopted as the first- and second-line regimens, respectively. However, the patient showed progressive disease (PD). Pembrolizumab was added as a third-line regimen (13 courses) after confirming PanNEC with high microsatellite instability (MSI-high). Despite a temporary partial response (PR), the patient showed PD by the end of the 13 courses and died 1 year and 7 months after diagnosis. Although there is no established PanNEC therapy, those with MSI-high may respond favorably to pembrolizumab. Therefore, we should ascertain the MSI status of any PanNEC in routine practice.

Histopathological comparison of aspiration and biopsy needles in endoscopic ultrasound-guided tissue acquisition in patients with subepithelial lesions.

BACKGROUND: Information on whether a fine-needle biopsy (FNB) needle can improve histopathological specimen quality or the amount of core tissue collected in the diagnosis of subepithelial lesions (SELs) remains insufficient. In this study, we aimed to compare the procedure outcomes and adequacy of histopathological specimens of fine-needle aspiration (FNA) and FNB needles in endoscopic ultrasound-guided tissue acquisition (EUS-TA) using sample isolation processing by stereomicroscopy (SIPS) in patients with SELs. METHODS: We performed a retrospective comparison of SEL cases registered in two previously conducted prospective studies. Of 61 cases, we identified 56 cases of SELs that involved the muscularis propria layer. Of these, 27 patients who underwent EUS-TA using a 22-gauge FNA needle between July 2016 and December 2017, and 29 patients who underwent the procedure using a 22-gauge FNB needle between March 2018 and January 2019 were included in the FNA and FNB group, respectively. RESULTS: Patient background characteristics did not differ between the groups. The technical success rate was 100% in both groups. The median adequacy score was significantly higher in the FNB group than in the FNA group (P < .01). The histological diagnosis showed no significant difference in the accuracy rate between the groups. CONCLUSIONS: In EUS-TA using the SIPS procedure to target SELs derived from the muscularis propria layer, FNB needles collect more core tissues and significantly improve histopathological specimen quality compared with FNA needles. When combined with SIPS, a high tissue diagnosis rate may be obtained regardless of the type of puncture needle used.

Pancreatic Schwannoma Diagnosed by Endoscopic Ultrasound-guided Fine-needle Aspiration.

A schwannoma is a tumor originating from Schwann cells. It is occasionally observed in the abdominal viscera in the form of a submucosal tumor derived from the gastric or duodenal muscularis propria. To date, only a few studies have reported on pancreatic schwannomas. Furthermore, very few patients are preoperatively diagnosed with pancreatic schwannoma because of the lack of established imaging characteristics distinguishing this type of schwannoma from other conditions. We herein report the first English publication of pancreatic schwannoma in which surgery was avoided because a pathological diagnosis was made solely on the basis of endoscopic ultrasound-guided fine-needle aspiration findings.