Comparison of clinical/histological outcomes according to puncture sites in endoscopic ultrasound-guided fine needle biopsy for large pancreatic masses: Multicenter randomized prospective pilot study.

OBJECTIVES: There are no recommendations regarding the optimal puncture site in endoscopic ultrasound-guided fine needle biopsy (EUS-FNB). This multicenter randomized prospective study compared the diagnostic accuracy and histological findings according to the sampling site for pancreatic masses larger than 3 cm. METHODS: Consecutive patients with pancreatic masses larger than 3 cm indicated for EUS-FNB were included in the study. Patients were randomly assigned to two groups for the initial puncture site (central vs. peripheral sampling of the masses). A minimum of four passes were performed, alternating between the center and the periphery. The primary outcome was diagnostic accuracy. RESULTS: A total of 100 patients were equally divided into the central group and the peripheral group. The final diagnosis revealed malignancy in 95 patients (pancreatic cancer [n = 89], neuroendocrine tumor [n = 4], lymphoma [n = 1], metastatic carcinoma [n = 1]), and benign conditions in five patients (chronic pancreatitis [n = 4], autoimmune pancreatitis [n = 1]). There was no significant difference in diagnostic accuracy between the puncture sites. However, combining samples from both areas resulted in higher diagnostic accuracy (97.0%) compared to either area alone, with corresponding values of 88.0% for the center (P = 0.02) and 85.0% for the periphery (P = 0.006). CONCLUSIONS: Both central sampling and peripheral sampling showed equivalent diagnostic accuracy in detecting malignancy. However, combining samples from both areas generated superior diagnostic yield compared to using either sampling site alone. For pancreatic masses larger than 3 cm, it is advisable to consider sampling from various areas of the masses to maximize the diagnostic yield.

The predictive value of PD-L1 expression in response to anti-PD-1/PD-L1 therapy for biliary tract cancer: a systematic review and meta-analysis.

Background: Recently, anti-programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) immunotherapy offers promising results for advanced biliary tract cancer (BTC). However, patients show highly heterogeneous responses to treatment, and predictive biomarkers are lacking. We performed a systematic review and meta-analysis to assess the potential of PD-L1 expression as a biomarker for treatment response and survival in patients with BTC undergoing anti-PD-1/PD-L1 therapy. Methods: We conducted a comprehensive systematic literature search through June 2023, utilizing the PubMed, EMBASE, and Cochrane Library databases. The outcomes of interest included objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) according to PD-L1 expression. Subgroup analyses and meta-regression were performed to identify possible sources of heterogeneity. Results: A total of 30 studies was included in the final analysis. Pooled analysis showed no significant differences in ORR (odds ratio [OR], 1.56; 95% confidence intervals [CIs], 0.94-2.56) and DCR (OR, 1.84; 95% CIs, 0.88-3.82) between PD-L1 (+) and PD-L1 (-) patients. In contrast, survival analysis showed improved PFS (hazard ratio [HR], 0.54, 95% CIs, 0.41-0.71) and OS (HR, 0.58; 95% CI, 0.47-0.72) among PD-L1 (+) patients compared to PD-L1 (-) patients. Sensitivity analysis excluding retrospective studies showed no significant differences with the primary results. Furthermore, meta-regression demonstrated that drug target (PD-1 vs. PD-L1), presence of additional intervention (monotherapy vs. combination therapy), and PD-L1 cut-off level (1% vs. ≥5%) significantly affected the predictive value of PD-L1 expression. Conclusion: PD-L1 expression might be a helpful biomarker for predicting PFS and OS in patients with BTC undergoing anti-PD-1/PD-L1 therapy. The predictive value of PD-L1 expression can be significantly influenced by diagnostic or treatment variables. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO, identifier CRD42023434114.

Rim enhancement of pancreatic ductal adenocarcinoma: investigating the relationship with DCE-MRI-based radiomics and next-generation sequencing.

Purpose: To identify the clinical and genetic variables associated with rim enhancement of pancreatic ductal adenocarcinoma (PDAC) and to develop a dynamic contrast-enhanced (DCE) MRI-based radiomics model for predicting the genetic status from next-generation sequencing (NGS). Materials and methods: Patients with PDAC, who underwent pretreatment pancreatic DCE-MRI between November 2019 and July 2021, were eligible in this prospective study. Two radiologists evaluated presence of rim enhancement in PDAC, a known radiological prognostic indicator, on DCE MRI. NGS was conducted for the tissue from the lesion. The Mann-Whitney U and Chi-square tests were employed to identify clinical and genetic variables associated with rim enhancement in PDAC. For continuous variables predicting rim enhancement, the cutoff value was set based on the Youden's index from the receiver operating characteristic (ROC) curve. Radiomics features were extracted from a volume-of-interest of PDAC on four DCE maps (Ktrans, Kep, Ve, and iAUC). A random forest (RF) model was constructed using 10 selected radiomics features from a pool of 392 original features. This model aimed to predict the status of significant NGS variables associated with rim enhancement. The performance of the model was validated using test set. Results: A total of 55 patients (32 men; median age 71 years) were randomly assigned to the training (n = 41) and test (n = 14) sets. In the training set, KRAS, TP53, CDKN2A, and SMAD4 mutation rates were 92.3%, 61.8%, 14.5%, and 9.1%, respectively. Tumor size and KRAS variant allele frequency (VAF) differed between rim-enhancing (n = 12) and nonrim-enhancing (n = 29) PDACs with a cutoff of 17.22%. The RF model's average AUC from 10-fold cross-validation for predicting KRAS VAF status was 0.698. In the test set comprising 6 tumors with low KRAS VAF and 8 with high KRAS VAF, the RF model's AUC reached 1.000, achieving a sensitivity of 75.0%, specificity of 100% and accuracy of 87.5%. Conclusion: Rim enhancement of PDAC is associated with KRAS VAF derived from NGS-based genetic information. For predicting the KRAS VAF status in PDAC, a radiomics model based on DCE maps showed promising results.

Impact of the suprapapillary method on patency in distal malignant biliary obstruction: a multicenter randomized controlled trial.

BACKGROUND AND AIMS: Placement of a self-expandable metal stent (SEMS) across the duodenal major papilla carries a risk of duodenobiliary reflux (DBR). The suprapapillary method of stent placement may reduce DBR and improve stent patency compared with the transpapillary method. This study compared the clinical outcomes between the suprapapillary and transpapillary methods for distal malignant biliary obstruction (DMBO). METHODS: Between January 2021 and January 2023, consecutive patients with DMBO from 6 centers in South Korea were randomly assigned to either the suprapapillary arm or transpapillary method arm in a 1:1 ratio. The primary outcome was the duration of stent patency, and secondary outcomes were the cause of stent dysfunction, adverse events, and overall survival rate. RESULTS: Eighty-four patients were equally assigned to each group. The most common cause of DMBO was pancreatic cancer (50, 59.5%), followed by bile duct (20, 23.8%), gallbladder (11, 13.1%), and other cancers (3, 3.6%). Stent patency was significantly longer in the suprapapillary group (median, 369 days [interquartile range, 289-497] vs 154 days [interquartile range, 78-361]; P < .01). Development of DBR was significantly lower in the suprapapillary group (9.4% vs 40.8%, P < .01). Adverse events and overall survival rate were not significantly different between the 2 groups. CONCLUSIONS: The placement of SEMSs using the suprapapillary method resulted in a significantly longer duration of stent patency. It is advisable to place the SEMS using the suprapapillary method in DMBO. Further studies with a larger number of patients are required to validate the benefits of the suprapapillary method. (Clinical trial registration number: KCT0005572.).

Quality Indicators of Endoscopic Retrograde Cholangiopancreatography in Korea.

Endoscopic retrograde cholangiopancreatography (ERCP) is a procedure that requires significant experiences and skills and has various procedure-related complications, some of which can be severe and even result in the death of patients. Expanding ERCP availability has the advantage of increasing accessibility for patients. However, ERCP poses a substantial risk if performed without proper quality management. ERCP quality management is essential for both ensuring safe and successful procedures and meeting the social demands for enhanced healthcare competitiveness and quality assurance. To address these concerns, the Korean Pancreatobiliary Association established a task force to develop ERCP quality indicators (QIs) tailored to the Korean medical environment. Key questions for five pre-procedure, three intra-procedure, and four post-procedure measures were formulated based on a literature search related to ERCP QIs and a comprehensive clinical review conducted by experts. The statements and recommendations regarding each QI item were selected through peer review. The developed ERCP QIs were reviewed by external experts based on the latest available evidence at the time of development. These domestically tailored ERCP QIs are expected to contribute considerably to improving ERCP quality in Korea.

Outcomes of Palliative Chemotherapy for Ampulla of Vater Adenocarcinoma: A Multicenter Cohort Study.

Background/Aims: : Palliative chemotherapy (PC) is not standardized for patients with advanced ampulla of Vater adenocarcinoma (AA). This multicenter, retrospective study evaluated first-line PC outcomes in patients with AA. Methods: : Patients diagnosed with AA between January 2010 and December 2020 who underwent PC were enrolled from 10 institutions. Overall survival (OS) and progression-free survival (PFS) according to the chemotherapy regimen were analyzed. Results: : Of 255 patients (mean age, 64.0±10.0 years; male, 57.6%), 14 (5.5%) had locally advanced AA and 241 (94.5%) had metastatic AA. Gemcitabine plus cisplatin (GP) was administered as first-line chemotherapy to 192 patients (75.3%), whereas capecitabine plus oxaliplatin (CAPOX) was administered to 39 patients (15.3%). The median OS of all patients was 19.8 months (95% confidence interval [CI], 17.3 to 22.3), and that of patients who received GP and CAPOX was 20.4 months (95% CI, 17.2 to 23.6) and 16.0 months (95% CI, 11.2 to 20.7), respectively. The median PFS of GP and CAPOX patients were 8.4 months (95% CI, 7.1 to 9.7) and 5.1 months (95% CI, 2.5 to 7.8), respectively. PC for AA demonstrated improved median outcomes in both OS and PFS compared to conventional bile duct cancers that included AA. Conclusions: : While previous studies have shown mixed prognostic outcomes when AA was analyzed together with other biliary tract cancers, our study unveils a distinct clinical prognosis specific to AA on a large scale with systemic anticancer therapy. These findings suggest that AA is a distinct type of tumor, different from other biliary tract cancers, and AA itself could be expected to have a favorable response to PC.