Next-Generation Sequencing Analysis of Pancreatic Cancer Using Residual Liquid Cytology Specimens from Endoscopic Ultrasound-Guided Fine-Needle Biopsy: A Prospective Comparative Study with Tissue Specimens.

This study evaluated the feasibility and clinical utility of liquid-based cytology (LBC) specimens via endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) for next-generation sequencing (NGS) of pancreatic cancer (PC). We prospectively evaluated the performance of DNA extraction and NGS using EUS-FNB samples obtained from PC. Thirty-three consecutive patients with PC who underwent EUS-FNB at our hospital were enrolled. DNA samples were obtained from 96.8% of the patients. When stratified with a variant allele frequency (VAF) > 10% tumor burden, the NGS success rate was 76.7% (n = 23) in formalin-fixed paraffin-embedded (FFPE), 83.3% (n = 25) in LBC, and 76.7% (n = 23) in frozen samples. The overall NGS success rate was 86.7% (n = 26) using FFPE, LBC, or frozen samples. The detection rates for the main mutated genes were as follows: 86.7% for KRAS, 73.3% for TP53, 66.7% for CDKN2A, 36.7% for SMAD4, and 16.7% for ARID1A. LBC had the highest median value of VAF (23.5%) for KRAS and TP53. PC mutation analysis using NGS was successfully performed using LBC compared with FFPE and frozen samples. This approach provides an alternative and affordable source of molecular testing materials.

Focal Type 2 Autoimmune Pancreatitis Mimicking Pancreatic Cancer: Treatment with Neoadjuvant Chemotherapy and Surgery.

A 51-year-old man was referred to our hospital for the further examination of main pancreatic duct interruption. Imaging findings showed a 25-mm-diameter mass lesion located in the pancreatic head. Endoscopic ultrasonography (EUS)-guided fine-needle aspiration (FNA) was performed on the mass. Cytology suggested adenocarcinoma, but the histological diagnosis was not confirmed. We made a comprehensive diagnosis of resectable pancreatic cancer. The mass shrank after preoperative adjuvant chemotherapy, and the patient underwent surgery. The final pathological diagnosis was type 2 autoimmune pancreatitis (AIP). Two years after surgery, AIP had not recurred in the remaining pancreas.

Comparison of recurrent biliary obstruction with the use of metal and plastic stents in EUS-guided biliary drainage: A propensity score-matched analysis.

Background and Objectives: In transpapillary biliary drainage, metal stents (MSs) exhibit a lower incidence of a biliary obstruction than plastic stents (PSs). However, few studies have compared recurrent biliary obstruction (RBO) when MSs and PSs are used in EUS-guided hepaticogastrostomy (EUS-HGS) and choledochoduodenostomy (EUS-CDS). We retrospectively evaluated the RBO for both stents in each procedure. Patients and Methods: : Between November 2012 and December 2020, 85 and 53 patients who underwent EUS-HGS and EUS-CDS for unresectable malignant biliary obstruction, respectively, were enrolled. Factors associated with RBO were assessed. Clinical outcomes were compared between the MS and PS groups using propensity score matching. Results: : The clinical success rate and procedure-related adverse events were similar in the MS and PS groups. Multivariate analysis identified the use of PS as a factor associated with RBO (EUS-HGS, P = 0.03; EUS-CDS, P = 0.02). After matching, the median time to RBO in EUS-HGS (MS: 313; PS: 125 days; P = 0.01) in the MS group was longer than that in the PS group. The cumulative incidence of RBO at 1, 3, and 6 months in the MS group was significantly lower than that in the PS group for EUS-HGS (MS: 4.0%, 8.2%, and 8.2%; PS: 12.4%, 24.9%, and 39.5%, respectively, P = 0.01). Conclusions: : MS exhibited a lower rate of RBO than PS for EUS-HGS and EUS-CDS.

Efficacy and safety of a novel anti-reflux metal stent during neoadjuvant chemotherapy for pancreatic cancer: A prospective multicenter exploratory study.

BACKGROUND/PURPOSE: The benefits of anti-reflux metal stents, used for treating biliary obstruction in patients receiving neoadjuvant chemotherapy (NAC) for pancreatic cancer, are yet unknown. Herein, the safety and efficacy of the novel duckbill-type anti-reflux metal stent (D-ARMS) were prospectively evaluated for biliary drainage. Additionally, the incidence of recurrent biliary obstruction (RBO) after placement of D-ARMS vs conventional covered self-expandable metal stents (CCSEMSs) was retrospectively compared. METHODS: Patients who received D-ARMS (n = 33) for treatment of distal biliary obstruction before NAC between September 2019 and January 2021 and those that received CCSEMSs (n = 38) between January 2013 and August 2019 were included in the historical control group. Technical and clinical successes, rate of RBO, and cumulative incidence of RBO were compared between the two groups. RESULTS: The technical success rate was 100% for both the D-ARMS and CCSEMS groups, and the clinical success rate were not significantly different (93.9% and 89.5%, respectively; P = .68). In the multivariate analysis, D-ARMS was identified as the independent factor for cumulative incidence of RBO (P = .03). The cumulative incidence of RBO was significantly lower in the D-ARMS group than that in the CCSEMS group (P = .04). CONCLUSIONS: D-ARMS is safe and effective for patients receiving NAC.

Role of apoptosis inhibitor of macrophages in patients with IgG4­related disease/autoimmune pancreatitis and the clinical characteristics associated with this condition.

Type 1 autoimmune pancreatitis (AIP) is a pancreatic manifestation of IgG4-related disease (IgG4-RD) and is a unique chronic inflammatory disease characterized by fibrosis. IgG4-RD is caused by an autoimmune mechanism that mimics malignant tumors and inflammatory disorders. Apoptosis inhibitor of macrophages (AIM) can function as a biomarker of autoimmune or inflammatory diseases with tissue fibrosis, including in inflammatory bowel disease and chronic liver disease. Therefore, the aim of the present study was to clarify the role of serum AIM levels and the clinical characteristics of patients with IgG4-RD and AIP. For this purpose, serum AIM concentrations were assessed using ELISA and the association between AIM and the laboratory and clinical data from patients with IgG4-RD/AIP, patients with pancreatic cancer (PC) and healthy controls (HCs), was determined. The results demonstrated that the serum AIM concentrations were not associated with the laboratory data. However, the serum AIM levels were significantly elevated in patients with AIP compared with the HCs and patients with PC. Furthermore, the serum AIM levels significantly decreased following steroid therapy in patients with AIP who were in remission. Overall, the present study demonstrates that serum AIM levels may be a potentially useful biomarker for the differential diagnosis of AIP and for evaluating the therapeutic reactivity of affected patients.

A case of immunoglobulin G4-related sclerosing mesenteritis without other organ involvement.

A 64-year-old man presented to our hospital with abdominal pain and 4-5 episodes of watery diarrhea per day for 2 months. Abdominal ultrasound examination revealed a mass in the peritoneal cavity, and computed tomography showed a 13.4 cm mass in the mesentery and a 3 cm mass in the mesocolon. The patient underwent laparoscopic partial resection for diagnosis. Microscopically, abundant fibrosis and numerous immunoglobulin (Ig) G4-positive plasma cells were observed. The serum level of IgG4 was 665 mg/dl postoperatively. These findings suggested that the lesion was consistent with IgG4-related sclerosing mesenteritis. Oral steroids resulted in rapid disappearance of symptoms and a decrease in masses. Recently, sclerosing mesenteritis are reported as IgG4-related disease or mimicking IgG4-related disease but multiple lesions rarely occur in the same organ. We report a case of IgG4-related sclerosing mesenteritis with multiple lesions without involvement of other organs, such as the pancreas and salivary glands.

Prognostic significance of extracellular volume fraction with equilibrium contrast-enhanced computed tomography for pancreatic neuroendocrine neoplasms.

BACKGROUND: /Objectives: Identifying reliable pretreatment imaging biomarkers for pancreatic neuroendocrine neoplasm (PanNEN) is a key imperative. Extracellular volume (ECV) fraction quantified with equilibrium contrast-enhanced CT can be easily integrated into routine examinations. This study aimed to determine whether ECV fraction with equilibrium contrast-enhanced computed tomography (CECT) could predict long-term outcomes in patients with PanNEN. METHODS: This study was a retrospective observational study of 80 patients pathologically diagnosed with PanNEN at a single institution. ECV fraction of the primary lesion was calculated using region-of-interest measurement within PanNEN and the aorta on unenhanced and equilibrium CECT. The impact of clinical factors and tumor ECV fraction on progression-free survival (PFS) and overall survival (OS) was assessed with univariate and multivariate analyses using Cox proportional hazards models. The correlation between WHO classification and tumor ECV fraction was evaluated using Kendall rank correlation coefficients. RESULTS: PFS and OS rates were estimated as 93.4% and 94.6%, 78.7% and 86.2%, 78.7% and 77.0%, and 78.7% and 66.6% at 1, 3, 5, and 10 years, respectively. Multivariate analysis revealed that Union for International Cancer Control (UICC) stage (hazard ratio [HR] = 3.95, P = 0.003), WHO classification (HR = 12.27, P = 0.003), and tumor ECV fraction (HR = 11.93, P = 0.039) were independent predictors of PFS. Patient age (HR = 1.11, P < 0.001), UICC stage (HR = 3.14, P = 0.001), and tumor ECV fraction (HR = 5.27, P = 0.024) were independent significant variables for predicting OS. Tumor ECV fraction had a weak inverse relationship with WHO classification (P = 0.045, τ = -0.178). CONCLUSIONS: ECV fraction determined by equilibrium CECT and UICC stage may predict survival in patients with PanNEN.

Factors Associated with the Technical Success of Bilateral Endoscopic Metallic Stenting with Partial Stent-In-Stent Placement in Patients with Malignant Hilar Biliary Obstruction.

BACKGROUND: Bilateral biliary drainage decreases the risk of cholangitis, but bilateral endoscopic metallic stenting is technically challenging. AIM: We retrospectively evaluated the factors associated with successful bilateral self-expanding metal stent (SEMS) placement using the partial stent-in-stent (PSIS) method for malignant hilar biliary obstruction and also assessed the safety and efficacy of this technique. METHODS: From April 2010 to February 2016, 47 consecutive patients (mean age, 73.0 ± 8.6 years; 32 males and 15 females) underwent PSIS placement for malignant hilar biliary obstruction in our hospital. The technical success of PSIS, clinical response, and complications were investigated. Factors associated with the technical success of PSIS were assessed. Using a propensity score-matched analysis, we compared the procedure time, clinical response, complications, stent patency, and survival time in 17 matched patients treated with bilateral SEMS placement using a SEMS delivery system of <6.0 or ≥6.0 Fr. RESULTS: The technical success rate was 77%. The clinical response rate was 91%, and the complication rate was 26%. Regarding complications, pancreatitis occurred in 5 patients (11%), cholangitis in 6 (13%), and cholecystitis in 1 (2%). A multiple logistic regression analysis identified the use of a SEMS with a delivery system < 6.0 Fr as a factor associated with technical success (P = 0.033; odds ratio, 10.769; 95% confidence interval, 1.205-96.212). In the 17 matched patients assigned according to the SEMS delivery system size, the procedure time was significantly shorter in those with a delivery system size < 6.0 Fr than in those with ≥6.0 Fr (P < 0.01). There were no significant differences in the clinical response, complication rate, stent patency, or survival time between the two groups. CONCLUSION: Using a delivery system < 6.0 Fr in size helped improve the technical success and reduced the procedure time for the placement of a SEMS by the PSIS method.