The SCRUM-Japan MONSTAR-SCREEN consortium is a nationwide molecular profiling project employing artificial intelligence–driven multiomics analyses for patients with advanced malignancies, aiming to develop novel therapeutics and diagnostics and deliver effective drugs to patients. Concurrently, studies assessing molecular residual disease–based precision medicine for resectable solid tumors, including CIRCULATE-Japan, are ongoing. The substantial data generated by these platforms are stored within a state-of-the-art supercomputing infrastructure, VAPOR CONE. Since 2015, our project has registered over 24,000 patients as of December 2023. Among 16,144 patients with advanced solid tumors enrolled in MONSTAR-SCREEN projects, 5.0% have participated in matched clinical trials, demonstrating a 29.2% objective response rate and 14.8-month median survival (95% CI, 13.4–16.3) for patients treated in the matched clinical trials. Notably, patients who received matched therapy demonstrated significantly prolonged overall survival compared with those who did not (hazard ratio 0.77; 95% confidence interval, 0.71–0.83). Significance: Our nationwide molecular profiling initiative played pivotal roles in facilitating the enrollment of patients with advanced solid tumors into matched clinical trials and highlighted the substantial survival benefits of patients treated with matched therapy. We aim to facilitate an industry–academia data-sharing infrastructure ecosystem, fostering new drug discovery paradigms and precision medicine.

Background/Aims: Covered self-expandable metallic stents (cSEMS) have become popular for endoscopic ultrasound-guided hepaticogastrostomy with transmural stenting (EUS-HGS). We compared the time to recurrent biliary obstruction (TRBO), complications, and reintervention rates between EUS-HGS using plastic stent (PS) and cSEMS in patients with unresectable malignancies at multicenter institutions in Japan.Methods: Patients with unresectable malignant biliary obstruction who underwent EUS-HGS between April 2015 and July 2020 at any of the six participating facilities were enrolled. Primary endpoint: TRBO; secondary endpoints: rate of complications other than recurrent biliary obstruction and technical success rate of reintervention were evaluated.Results: PS and cSEMS were used for EUS-HGS in 109 and 43 patients, respectively. The TRBO was significantly longer in the cSEMS group than in the PS group (646 vs. 202 days). Multivariate analysis identified two independent factors associated with a favorable TRBO: combined EUS-guided antegrade stenting with EUS-HGS and the use of cSEMS. No significant difference was observed in the rate of complications other than recurrent biliary obstruction between the two groups. The technical success rate of reintervention was 85.7% for PS and 100% for cSEMS (p=0.309).Conclusions: cSEMS might be a better option for EUS-HGS in patients with unresectable malignancies, given the longer TRBO.

Advanced gastric and gastroesophageal junction cancers (GC/GEJCs) harbor diverse molecular signatures, highlighting the need for intricate evaluations to identify potential therapeutic targets. Although whole‐transcriptome sequencing (WTS) has emerged as a useful tool for understanding these molecular intricacies, its clinical implications have yet to be fully elucidated. This study evaluated the correlation between immunohistochemistry (IHC) and WTS, compared their clinical significance, and identified potential therapeutic targets undetectable through IHC alone. We enrolled 140 patients with advanced GC/GEJC and assessed them using IHC for six pivotal biomarkers: claudin‐18 (CLDN18), human epidermal growth factor receptor 2 (HER2), multiple receptor tyrosine kinases (RTKs), and programmed death ligand 1 (PD‐L1). Concurrently, WTS was employed as part of the analyses in MONSTAR‐SCREEN‐2, a multicenter multiomics study. IHC analysis revealed 16.4% HER2, 39.3% CLDN18 (2+/3 + ≥75%), and 15.8% PD‐L1 (combined positive score ≥ 10) positivity, among other molecular markers. Significant correlations were observed between IHC and WTS for all six pivotal biomarkers. Among nineteen HER2 IHC‐positive patients treated with anti‐HER2 therapeutics, ERBB2 status in WTS was significantly associated with progression‐free survival (ERBB2‐high vs. ‐low: median 9.0 vs. 5.6 months, log‐rank p = 0.046). IHC‐based molecular profiling revealed significantly high expression of CLDN18 in RTK‐negative patients, with 78.4% positive for either CLDN18 or PD‐L1. Additionally, WTS revealed elevated expression of pivotal biomarkers in patients displaying negative targetable biomarkers via IHC. Our findings highlighted the significant correlation between IHC and WTS, reinforcing the clinical utility of WTS. A subset with IHC‐negative but WTS‐positive status may benefit from specific biomarker‐targeted therapies.

Precision medicine in cancer treatment refers to targeted therapy based on the evaluation of biomarkers. Although precision medicine for pancreatic cancer (PC) remains challenging, novel biomarker-based therapies, such as pembrolizumab, olaparib, and entrectinib, have been emerging. Most commonly, endoscopic ultrasound-guided tissue acquisition (EUS-TA) had been used for the diagnosis of PC until now. However, advances in EUS-TA devices and biomarker testing, especially next-generation sequencing, have opened up the possibility of sequencing of various genes even in limited amounts of tissue samples obtained by EUS-TA, and identifying potential genetic alterations as therapeutic targets. Precision medicine benefits only a small population of patients with PC, but biomarker-based therapy has shown promising results in patients who once had no treatment options. Now, the role of EUS-TA has extended beyond diagnosis into decision-making regarding the treatment of PC. In this review, we mainly discuss tissue sampling by EUS-TA for biomarker testing and the current status of precision medicine for PC.

Objectives: Endoscopic-ultrasound-guided hepaticogastrostomy (EUS-HGS) with plastic stent placement is associated with a high incidence of adverse events that may be reduced using an endoscopic retrograde cholangiopancreatography (ERCP) contrast catheter in the track dilation step. In this study, we evaluated the usefulness of track dilation and bile aspiration performed with an ERCP contrast catheter in EUS-HGS with plastic stent placement. Methods: In a multicenter setting, 22 EUS-HGS cases dilated with an ERCP contrast catheter were analyzed retrospectively and compared between a bile aspiration group and no bile aspiration group. Results: Overall, adverse events occurred in three (13.6%) cases of bile leakage, three (13.6%) cases of peritonitis, and one (4.5%) case of bleeding. Comparing patients with and without bile aspiration, 6 of the 11 patients (54.5%) with no bile aspiration had adverse events, whereas only 1 of the 11 patients (9.1%) who had bile aspiration, as much bile as possible, had an adverse event (bleeding). In univariate analysis, the only factor affecting the occurrence of adverse events was bile aspiration whenever possible (odds ratio, 12.0; 95%CI 1.12–128.84). Conclusions: In EUS-HGS with plastic stent placement, track dilation and bile aspiration with an ERCP contrast catheter may be useful in reducing adverse events.

Background and objective: Endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard for managing malignant biliary obstruction (MBO), but it is challenging in patients with surgically altered anatomy (SAA). EUS-guided hepaticogastrostomy (EUS-HGS) and enteroscopy-assisted ERCP are alternative techniques, but their comparative efficacy and safety in this population are not well-researched. Herein, we evaluated the outcomes of EUS-HGS versus single-balloon–assisted enteroscopy ERCP (SBE-ERCP) in MBO patients with SAA. Patients and methods: This retrospective study included 70 patients with MBO who underwent EUS-HGS (n = 29) or SBE-ERCP (n = 41) at a single center between April 2015 and June 2024. Data on the patient characteristics, procedure details, time to recurrent biliary obstruction (TRBO), and adverse events (AEs) were analyzed. Results: The EUS-HGS group showed a higher technical success rate (100% vs. 68%, P = 0.002), shorter procedure time (23 vs. 50 min, P < 0.001), and longer TRBO (251 vs. 103 d, P = 0.020) as compared with the SBE-ERCP group. Subgroup analysis revealed that pancreatobiliary cancer and SBE-ERCP were significantly associated with a shorter TRBO. When stratified by stent type, the median TRBO in the SBE-ERCP with PS group was 49 days, serving as the reference. In comparison, the median TRBO was 140 days in the SBE-ERCP with the self-expandable metallic stent group (hazard ratio [HR], 0.46; P = 0.181), 127 days in the EUS-HGS with PS group (HR, 0.38; P = 0.055), and 701 days in the EUS-HGS with the self-expandable metallic stent group (HR, 0.13; P = 0.014). The overall incidence of AEs was comparable between the 2 groups (20.6% vs. 17.1%), and there were no severe AEs. Regarding reintervention, there was no significant difference in technical success rate and procedure time between EUS-HGS and SBE-ERCP. Conclusion: EUS-HGS was associated with a superior technical success rate, shorter procedure time, and longer stent patency, without an increased risk of AEs, as compared with SBE-ERCP. Thus, EUS-HGS should be appropriate for managing MBO patients with SAA.