Ikeda, Masafumi

Abstract In recent years, there has been increasing interest in the possible prognostic impact of concomitant medications in patients with cancer treated with immunotherapy combinations. This real‐world analysis aims to evaluate the impact of concomitant medications on survival outcomes in patients with advanced biliary tract cancer (BTCs) treated with cisplatin, gemcitabine and durvalumab (CGD) therapy. The study cohort included patients with a diagnosis of advanced BTCs who were taking concomitant medications for their comorbidities before the start of CGD. The primary objectives were overall survival (OS) and progression‐free survival (PFS). The initial population consisted of 666 patients, who were retrospectively collected from 41 sites in 12 countries. Data on concomitant medications were available for 493 patients. After a median follow‐up of 8.8 months (95% CI: 7.8–9.8), patients who did not take steroids (prednisone >10 mg/day or equivalent) or nonsteroidal anti‐inflammatory drugs (NSAIDs) and opioids, before the start of CGD, had longer OS and PFS in univariate analysis. The multivariate analysis confirmed longer OS for patients who did not take steroids. Patients who did not take steroids had an OS of 14.8 months (95% CI: 13.1–29.1) versus 5.0 months (95% CI: 2.14–11.32) of patients who took prednisone >10 mg/day or equivalent. No differences were reported in terms of overall response rate (ORR), disease control rate (DCR) ( p = 1.0 and p = .16, respectively), and safety profile between the two groups. Our analysis suggests that patients who did not receive steroids before the start of GCD had longer survival and highlighted the relevance of balancing concomitant medications and chemoimmunotherapy.

ABSTRACT 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.

Abstract Background Cisplatin, gemcitabine, and durvalumab combination is a standard first-line treatment for advanced biliary tract cancer. This study aimed to assess the impact of genetic alterations on outcomes in patients with advanced biliary tract cancer treated with cisplatin, gemcitabine, and durvalumab in real-world clinical practice. Methods Patients with unresectable, locally advanced, or metastatic biliary tract cancer treated with cisplatin and gemcitabine plus durvalumab across 39 centers in 11 countries in Europe, the United States, and Asia were included in this analysis. Results The cohort included 513 patients with advanced biliary tract cancer. The 5 most frequently altered genes were TP53 (22.1%), KRAS (13.7%), CDKN2A/B (13.6%), ARID1A (12.2%), and IDH1 (9.2%). In multivariate analysis, SMAD4 mutations were associated with improved progression-free survival (PFS) (hazard ratio [HR] = 0.49, P = .018) and overall survival (HR = 0.11, P = .023), while TP53 mutations were linked to worse PFS (HR = 1.62, P = .0047) and TERT mutations to worse overall survival (HR = 8.92, P = .0012). No other genomic alterations were statistically associated with outcomes. Subgroup analysis showed that TP53 mutations negatively affected PFS and overall survival in intrahepatic cholangiocarcinoma, while KRAS mutations were associated with poorer PFS in extrahepatic cholangiocarcinoma. No gene alterations were linked to outcomes in gallbladder cancer. Conclusions This large-scale analysis, with comprehensive molecular profiling, supports the positive prognostic impact of SMAD4 mutations for PFS and overall survival and highlights the negative prognostic roles of TP53 (PFS) and TERT (overall survival) mutations, providing valuable insights for personalized treatment strategies in biliary tract cancer.

ABSTRACT Background Over the years, prognostic indexes have been developed to help clinicians stratify patients with biliary tract cancers (BTC) into risk groups. This study aims to identify a new prognostic index for patients with BTC treated with cisplatin, gemcitabine and durvalumab (CGD) in the first‐line setting. Patients and Methods The study population consisted of patients with BTC from 11 Eastern and Western Countries. Using multivariate analysis for overall survival (OS), we identified 5 baseline statistically significant variables: stage, carcinoembryonic antigen (CEA) levels, albumin levels, gamma glutamyl transferase (GGT) levels, neutrophil‐to‐lymphocyte ratio (NLR). Metastatic disease is a prognostic factor with a superior weight considering the HR of 3.62, while all the others can be considered prognostic factors with equivalent weight as the HRs are quite similar (HRs between 1.55 and 1.92). Based on these reasons, we developed a prognostic model called the MAGIC‐D index by assigning a score of 2 for metastatic disease, and a score of 1 for CEA increased levels, albumin decreased levels, GGT increased levels, NLR ≥ 3. Patients were stratified into three risk groups as follows: low‐risk group (Score from 0 to 2), intermediate‐risk group (Score from 3 to 4) and high‐risk group (Score from 5 to 6). At the first data cutoff (April 2024), these data were available for 319 patients that composed the training cohort used for the analysis. At the second data cutoff (May 2025), 79 patients were further enrolled and composed the validation cohort. Results Median progression‐free survival was 11.7 months in low‐risk group (20.7%), 8.7 months in intermediate‐risk group (46.4%) and 5.4 months in high‐risk group (32.9%) [low‐risk hazard ratio (HR): 0.27, intermediate‐risk HR: 0.55, high‐risk HR: 1, p < 0.0001]. Median OS was 18.4 months in low‐risk group,15.9 months in intermediate‐risk group and 7.8 months in high‐risk group (low‐risk HR: 0.17, intermediate‐risk HR: 0.43, high‐risk HR: 1, p < 0.0001). There was no difference in overall response rate (low‐risk: 31.8%, intermediate‐risk: 36.5% and high‐risk: 25.7%; p = 0.0718), while disease control rate was significantly different across the three risk groups (low‐risk: 83.3%, intermediate‐risk: 70.9% and high‐risk: 60.9%; p < 0.0001) as well as the rate of patients receiving a second‐line therapy (low‐risk: 54.5%, intermediate‐risk: 48.6% and high‐risk: 25.7%; p = 0.0061). Finally, the prognostic role in terms of OS and PFS of the MAGIC‐D index was confirmed in a validation cohort of 79 patients. Conclusion The MAGIC‐D index is an easy‐to‐use tool able to stratify patients with BTC with different prognoses undergoing first‐line therapy with CGD.

4119 Background: TP53 mutations are frequent genetic alterations in cancers and also prevalent in biliary tract cancer (BTC). In non-small cell lung cancer, TP53 mutations have been reported to enhance immune checkpoint inhibitor (ICI) efficacy and improve outcomes. However, their impact on BTC remains unclear. This study investigated the clinico-molecular characteristics, prognosis, and ICI efficacy in TP53 -mutated BTC. Methods: Patient data were collected from the SCRUM-Japan GOZILA and MONSTAR-SCREEN-1/2 databases (Japan) and the Duke university and Mayo clinic databases (U.S.), which included patients receiving first-line ICI therapy. Comparisons between TP53 wild-type (WT) and mutation groups were performed in the Japanese cohort. Subsequently, analyses were expanded to include U.S. patients, focusing on comparisons between non-ICI and ICI groups. Tumor Immune Dysfunction and Exclusion (TIDE) scores were calculated using MONSTAR-SCREEN-2 whole transcriptome sequencing (WTS) data to evaluate ICI responsiveness, and gene set enrichment analysis (GSEA) explored pathways associated with TP53 mutations. Results: In the Japanese cohort (n=594), TP53 mutations were identified in 311 patients (52.4%). KRAS , ERBB2 , CDKN2A , and SMAD4 alterations were more frequent in the TP53 mutation group, while IDH1, BAP1 , and FGFR2 fusions were more common in the WT group. Multivariable analysis showed TP53 mutations were independent prognostic factors for poor outcomes (progression-free survival [PFS]: HR 1.37, 95% CI: 1.11–1.69, P=0.003; overall survival [OS]: HR 1.36, 95% CI: 1.06–1.75, P=0.017). Incorporating the U.S. cohort (n=625; non-ICI: 548; ICI: 77), no significant differences in overall response rate (ORR) or disease control rate (DCR) were observed in the non-ICI group between the groups. However, in the ICI group, TP53 mutations tended to show higher ORR (21.1% vs. 38.5%, P=0.16) and DCR (47.4% vs. 66.7%, P=0.14). In the non-ICI group, TP53 mutations were associated with worse PFS (HR 1.46, median PFS: 7.4 vs. 5.3 months, P<0.001), whereas, in the ICI group, no significant difference was observed; however, a trend toward better PFS was seen in the TP53 mutation group (median PFS: 5.0 vs. 6.4 months, P=0.163). TIDE scores were significantly lower in the TP53 mutation group, indicating higher ICI responsiveness. GSEA revealed enrichment of oxidative phosphorylation and hypoxia pathways. Conclusions: TP53 mutations are independent prognostic factors for poor outcomes in BTC. However, patients with TP53 mutations may derive greater benefits from ICIs, underscoring the importance of tailored therapeutic strategies in TP53- mutated BTC.

AbstractStandard of care first‐line systemic treatment for advanced biliary tract cancer includes chemo‐immunotherapy with gemcitabine, cisplatin, and durvalumab, followed by maintenance durvalumab monotherapy. The present work aims to investigate the differences in baseline clinical and molecular characteristics between patients with early progression during chemo‐immunotherapy and those who reach durvalumab maintenance therapy. The study population included patients with unresectable, locally advanced, or metastatic BTC who received treatment at 38 clinical Institutions in 12 countries from July 2021 to December 2023. The primary objective of the study was to investigate whether baseline clinical and molecular characteristics differed between patients with early progression during chemo‐immunotherapy versus those reaching durvalumab maintenance therapy. Four hundred forty‐eight patients were included in this study. Two hundred twenty‐seven patients (50.7%) received maintenance with durvalumab monotherapy, whereas 221 (49.3%) did not receive maintenance therapy due to PD during first‐line chemo‐immunotherapy before completing 8 cycles. Results show that patients who received maintenance were more likely to be older (≥70 years), have an ECOG = 0, locally advanced disease, and a neutrophil‐to‐lymphocyte ratio (NLR) <3. A higher proportion of patients with BAP1 mutations received maintenance, while TP53 mutations were more common in those who progressed early. According to the present analysis, a substantial proportion of patients (50.7%) with advanced BTC who were treated with chemotherapy plus durvalumab proceeded to receive maintenance therapy with durvalumab monotherapy, with a median treatment duration of 4.4 cycles. Patients ≥70 years, with ECOG PS 0, with locally advanced disease, and with NLR <3 had a higher likelihood of receiving maintenance therapy.

PURPOSE This study aimed to investigate the clinicomolecular profiles and the efficacy of human epidermal growth factor receptor 2 (HER2)-targeted therapy in HER2 -amplified biliary tract cancer (BTC). METHODS This study was an international collaboration that used combined data from the prospective SCRUM-Japan GOZILA and MONSTAR-SCREEN in Japan and retrospective reviews in the United States; patients with advanced BTC who had received systemic therapy were included. The clinicomolecular profiles were evaluated in an exploratory cohort, whereas the efficacy of HER2-targeted therapy was assessed in a biomarker-selected cohort. RESULTS Of the 439 patients in the exploratory cohort, 43 (10%) had HER2 amplification. The frequencies of coalterations were higher in patients with HER2 amplification versus patients without HER2 amplification including HER2 mutations (26% v 5%, P < .001), TP53 mutations (84% v 61%, P = .003), and BRAF amplification (9% v 2%, P = .030). There were no KRAS mutations identified in patients with HER2- amplified BTC. No significant difference in overall survival (OS) was observed between patients with and without HER2 amplification (median, 17.7 v 16.9 months; hazard ratio [HR], 0.95 [95% CI, 0.65 to 1.40]). Of the 60 patients with HER2 -amplified BTC in the biomarker-selected cohort (43 from Japan and 17 from the United States), the OS was significantly longer in 29 patients who received HER2-targeted therapy than in those who did not receive HER2-targeted therapy (median, 24.3 v 12.1 months; HR, 0.39 [95% CI, 0.23 to 0.82]). Multivariate analysis identified HER2-targeted therapy as an independent prognostic factor for OS (HR, 0.29 [95% CI, 0.14 to 0.58]; P < .001). CONCLUSION HER2 amplification was found in 10% of advanced BTC and was not identified as an independent prognostic factor for OS. Patients with HER2 -amplified BTC derive significant benefit from HER2-targeted therapy.

243 Background: HER2-amplified aCRC is associated with poor prognosis despite new anti-HER2 regimens. Insight on biomarkers that predict response to these therapies is limited. This study aims to evaluate whether baseline alterations in oncogenic drivers along the HER2 pathway predict response to anti-HER2 therapy in HER2-amplified aCRC. Methods: In this international multi-center study involving Mayo Clinic, Duke Cancer Institute and National Cancer Center Hospital East (Japan), we collected baseline genomic alterations from tissue or blood samples using next-generation sequencing (NGS) prior to anti-HER2 therapy initiation. We defined PIK3CA, RAS, RAF, MAP2K, and MET as oncogenic drivers of resistance within the HER2 pathway. Overall survival (OS) was evaluated with the Kaplan-Meier method and a log-rank test was used to compare median OS (mOS) between pts with and without alterations in the above genes. A chi-square test (significance level 0.05) was performed to compare overall response rate (ORR) and disease control rate (DCR). Results: We identified 39 pts with HER2-amplified aCRC and baseline NGS. Median age was 57 (range 30-77), 54% were male. Baseline alterations in HER2 pathway oncogenic drivers were identified in 17 pts (43.5%). 18 (46%) received monoclonal antibodies (mAbs) plus tyrosine kinase inhibitors, 12 (30%) received dual mAbs and 7 (18%) received trastuzumab deruxtecan. The mOS was 41.9 months (mos) (95%CI 23.7-60.1) for other alterations vs 24.2 mos (95%CI 14.1-34.3) in pts with HER2 pathway alterations (p = 0.1). ORR was 47% vs 41% (p = 0.7) and DCR 82% vs 73% (p = 0.4), for pts with HER2 pathway alterations and without HER2 pathway alterations, respectively. 4 pts receiving trastuzumab/tucatinib had complete response, none of which had HER2 pathway alterations. Conclusions: Pts with baseline alterations in oncogenic drivers of the HER2 pathway had clinically worse outcomes compared to pts without such alterations despite receiving HER2-targeted therapy, though results lacked statistical significance. Larger studies are needed to confirm the lack of benefit from anti-HER2 therapy in this subgroup.

628 Background: Biliary tract cancers (BTC) are aggressive malignancies with poor survival outcomes and limited treatment options. This study compared the epidemiological and molecular differences of advanced BTC patients through a global collaboration involving the Mayo Clinic and National Cancer Center Hospital East. Methods: We included patients with advanced BTC who underwent comprehensive tumor molecular profiling who received at least 30 days of systemic therapy. Patients were grouped based on specific alterations. Overall survival (OS) was calculated from the start of first-line therapy until death and compared among subgroups using Cox regression models. Results: 332 (36%) out of 932 patients had at least one actionable mutation : somatic BRCA1/2 mutations N=106, FGFR2 fusions N=61, HER2 amplifications N=65, KRAS G12C/D mutations N=46, IDH1 mutations N=38, and TMB >10 mut/Mb N=16. BRCA1/2 -mutated BTC were more commonly found in older Asian males with intrahepatic tumors and often presented with peritoneal and liver metastases upon initial diagnosis. FGFR2 fusions were more prevalent in younger White females with intrahepatic tumors, while HER2 amplifications were mainly seen in Asian females with gallbladder tumors. KRAS mutations were primarily observed in Asian males, and IDH1 mutations were common in White males with intrahepatic tumors, frequently presenting with liver metastasis. Survival outcomes varied significantly based on the alteration type: patients with FGFR2 fusions had the longest median OS (mOS) at 23.3 months (mo) (95%CI 18.4-34.9), followed by those with IDH1 mutations (19.3 mo; 95% CI 17.4-NE) and TMB >10 mut/Mb (17.8 mo; 95% CI 13.6-NE). BRCA mutations had a mOS of 16 mo (95% CI 14.6-19.8), while HER2 amplifications and KRAS mutations had mOS of 15.5 (95% CI 11.9-20.2) and 11.6 mo (95% CI 10.0-20.9), respectively. Conclusions: These findings underscore the heterogeneity in clinical and genomic characteristics among BTC patients, highlighting the importance of tailored therapeutic approaches. Baseline patient characteristics stratified by mutation status. KRAS G12C/D (N=46) BRCA 1/2 (N=106) IDH1 (N=38) HER2 amplification(N=65) FGFR2 fusion(N=61) TMB>10 mut/Mb(N=16) P-value Median Age, year 67 68 64 66 52 73 <0.001 Female, n (%) 19 (41) 34 (32) 18(47) 34 (52) 45(74) 6 (38) <0.001 Race, n (%) <0.001 Asian 31 (67) 97 (92) 13 (34) 51 (79) 10 (16) 6 (38) White 14 (30) 8 (8) 24 (63) 13 (20) 48 (79) 10 (63) Primary tumor location, n (%) <0.001 Intrahepatic 28 (68) 45 (45) 33 (100) 19 (31) 54(95) 10 (67) Extrahepatic 9 (22) 27(27) 0 (0) 10 (16) 2 (4) 4 (27) Gallbladder 4 (10) 28 (28) 0 (0) 32 (53) 1 (2) 1 (7) Sites of Metastasis at diagnosis, n (%) Abdominal Wall / Peritoneal 9 (24) 15 (19) 4(13) 7 (12) 6 (10) 4 (27) 0.309 Bone 33 (92) 70 (90) 26 (87) 2 (3) 9(15) 0 (0) 0.212 Liver 20 (49) 52 (61) 28 (82) 45 (73) 45 (76) 6 (38) 0.001 Lung 26 (70) 65 (82) 22 (69) 36 (58) 27(45) 11 (69) 0.006