Citations

Abstract Background Emerging evidence suggests irreversible electroporation (IRE) with standard-of-care (SOC) chemotherapy may improve survival in patients with Stage 3 pancreatic ductal adenocarcinoma (PDAC) when compared to SOC alone. This study evaluates the overall survival (OS) and progression-free survival (PFS) of Stage 3 PDAC patients treated with SOC plus IRE with the NanoKnife System versus SOC alone. Methods This prospective, multicenter study included two cohorts from the DIRECT registry: an IRE cohort from sites offering IRE as part of clinical care, and a comparator SOC cohort of prospectively enrolled and contemporaneous retrospective patients. Enrollment spanned 08/05/2019 to 02/05/2023, with follow-up through at least 24 months, death, or loss to follow-up. Included were 137 patients (99 IRE; 38 SOC), aged ≥18 years with Stage 3 PDAC and no progression after three months of SOC therapy. Results Median (interquartile range) time from diagnosis to enrollment was 8 (6-10) months for IRE and 4 (3-6) for SOC (p<0.0001). Median OS and PSF from enrollment were 18 (95% confidence interval [CI]: 15-24) months and 9 (95% CI: 7-12) months for IRE, and 10 (95% CI: 8-14) months and 6 (5-8) months for SOC, respectively (p<0.0001 and p=0.009). Adverse events occurred in 80% (79/99) of IRE patients and 95% (36/38) of SOC patients; 29% (29/99) of the IRE cohort experiencing an IRE-related adverse event. Conclusions IRE was associated with improved OS versus SOC alone and may be an effective consolidative treatment for Stage 3 PDAC after three months of induction chemotherapy.

Background and Aims: Cholangiocarcinoma (CCA) is a rare but aggressive malignancy with poorly understood genetic susceptibility. To date, genome-wide association studies (GWAS) investigating germline variants associated with CCA risk remain limited. We aimed to identify genetic risk loci for CCA and its clinical subtypes through comprehensive GWAS and post-GWAS analyses. Approach and Results: We conducted a GWAS of 2366 CCA cases and 11,750 controls of European ancestry. Genome-wide significant loci ( p <5×10 −8 ) were identified and further examined through fine-mapping, functional annotation, and HLA imputation. Subgroup analyses were conducted by CCA subtypes and primary sclerosing cholangitis (PSC) status. Cross-trait linkage disequilibrium score regression and Mendelian randomization were employed to investigate the shared genetic architecture and potential causal relationships with a diverse range of traits. We identified 1 new genome-wide significant variant, rs535777 (OR=1.44), near HLA-DRB1/DQA1 associated with CCA, and 2 variants associated with extrahepatic CCA: rs116224263 (OR=0.17) in LINC02506 at 4p15.1 and rs6914950 (OR=1.63) near HLA-DRB1/DQB1 . Stratified analyses revealed rs2395184 (OR=3.51) near HLA-DRA/DRB5 associated with PSC-related CCA, and rs142674434 (OR=2.98) in THSD7A at 7p21.3 associated with non-PSC-related CCA. HLA imputation uncovered new amino acid residues associated with disease risk. Cross-trait analyses identified shared genetic signals between CCA and anthropometric, lipidemic, lifestyle, and medical traits. Mendelian randomization supported putative causal associations for 12 traits with CCA or its subtypes. Conclusions: Our large-scale GWAS highlights new genetic variants and HLA-linked mechanisms underlying CCA susceptibility. Integrating multi-step post-GWAS approaches enhances understanding of CCA pathogenesis and may facilitate the development of risk biomarkers for early detection and precision prevention strategies.

Background: Splanchnic venous thrombosis (SVT) is a potentially severe and frequently underdiagnosed complication following splenectomy in patients with hematologic diseases. Despite its clinical importance, no standardized, evidence-based guidelines currently exist to inform perioperative prevention, diagnosis, or treatment in this population. Materials and Methods: A systematic review and meta-analysis were conducted following PRISMA guidelines to estimate the incidence and risk factors for SVT after splenectomy in patients with hematologic diseases. Twenty-eight observational studies comprising 5025 patients were included. Risk factor data were analyzed using random-effects models. In parallel, an international Delphi consensus process was performed involving 35 experts (hematologists and surgeons) from 14 countries. Experts were assigned to five domain-specific groups and developed clinical statements on prophylaxis, diagnosis, and management of SVT. Consensus was defined as ≥80% agreement, and recommendations were graded using the GRADE framework. Results: The pooled incidence of SVT after splenectomy was 11.4%, with higher rates in studies using routine imaging (20.7%) and those conducted at single centers (15.1%). Splenic size and weight were significant risk factors, while age, BMI, and platelet count were not. Disease-specific risk was highest in patients with myeloproliferative neoplasms, lymphoma, and thalassemia. The Delphi process generated 25 consensus statements, 14 of which were classified as strong recommendations. Key guidance included perioperative vaccination, individualized thromboprophylaxis with BMI-adjusted low molecular weight heparin, selective Doppler-based screening in high-risk patients, and stepwise anticoagulation regimens based on thrombus burden and clinical evolution. Conclusion: This study presents the first international consensus-based guidelines for managing SVT after splenectomy in patients with hematologic disease. Developed through systematic evidence synthesis and expert consensus, these recommendations provide a practical framework rather than definitive standards of care and support individualized prevention, detection, and treatment strategies in this high-risk population.

Background Pancreatoduodenectomy (PD) is the only curative treatment for pancreatic cancer. Neoadjuvant therapy (NAT) has enhanced survival, especially for downstaging advanced tumors, while also introducing complexities and new complications. Despite surgical advances, some PD attempts remain unsuccessful. The management of these cases is not well defined. This study analyzes outcomes of repeat PD performed by two high-volume surgeons following previously unsuccessful attempts. Methods We retrospectively analyzed patients with pancreatic neoplasm undergoing successful pancreaticoduodenectomy (2013-2024) at two high-volume centers under two experienced surgeons. Only cases with prior aborted PD attempts for non-metastatic disease were included. Data from institutional records provided outcomes on failure reasons, procedure timing, surgical details, and 90-day complications. Results Of the 858 PD cases, 18 patients (2.1%; 12 males, 6 females; median age 69 years) had prior unsuccessful PD attempts at other institutions. Initial tumors were borderline resectable (33.3%), resectable (22.2%), or locally advanced (22.2%). Main causes for initial failure were vascular involvement (41.2%) and tumor infiltration (17.6%). Median time between attempts was 246 days, with 77.8% receiving chemotherapy before the second attempt. The second procedure achieved R0 resection in 94.4% of cases. Major 90-day complications occurred in 23.5% of patients, with no perioperative mortality. Disease recurrence occurred in 38.9% within the first year. Conclusion Repeat PD after an aborted attempt is feasible in select patients at specialized centers. However, complication and recurrence rates emphasize the need for careful patient selection. Further research is needed to optimize management strategies.

AbstractBackgroundGastric cancer with synchronous peritoneal metastases is a debilitating disease with limited treatment options. This article describes an update of the 2018 Chicago Consensus guidelines addressing the management of gastric cancer with synchronous peritoneal metastases in line with the most recent evidence.MethodsA clinical management pathway was updated through two rounds of a Delphi consensus to assess agreement levels with pathway blocks. Supporting evidence underwent evaluation using a rapid literature review. Meta‐analyses were performed as appropriate.ResultsOverall, the level of evidence in this disease subset was low to moderate. Of 124 participants in the first round, 109 (88%) responded in the second round. Strong consensus (>90%) was achieved in six of eight blocks (75%) in rounds 1 and 2. A multidisciplinary preoperative assessment and diagnostic laparoscopy should be offered to all patients, whereas patients with a high burden of disease or progression should undergo nonsurgical management. Patients with stable/responsive disease and a low peritoneal carcinomatosis index should subsequently be offered treatment with regional therapeutic interventions and cytoreductive surgery. In patients who are cytology‐positive, systemic therapy can be used to convert them to cytology‐negative, with subsequent surgery offered according to the patient's goals of care. Meta‐analysis of observational and randomized control trials revealed a survival benefit with the addition of intraperitoneal chemotherapy to cytoreductive surgery (hazard ratio, 0.52).ConclusionsThe consensus‐driven clinical pathway for gastric cancer with synchronous peritoneal metastases offers vital clinical guidance for practitioners. There is a growing body of high‐quality evidence to support management strategies, and future clinical trials are eagerly awaited.

AbstractNeuroendocrine neoplasms (NENs) with peritoneal metastases (PM) represent a complex clinical challenge because of low incidence and heterogeneous phenotypes. This commentary describes the results of a national consensus aimed at addressing clinical management of patients with NENs and PM. An update of the 2018 Chicago consensus guidelines was conducted with a modified Delphi technique, which encompassed two rounds of voting. The levels of agreement for various pathway blocks were assessed, and key systemic therapy concepts were summarized by content experts. Supporting evidence was evaluated via a rapid literature review. Overall, the level of evidence for the management of PM in this disease was universally low. In total, 107 participants responded in the first round, with 88 of 107 (82%) participating in the second round. Strong consensus (>90%) was achieved in five of seven (71%) and seven of seven (100%) blocks in rounds 1 and 2, respectively. A multidisciplinary approach including psychosocial and wellness assessments received a strong positive recommendation. Management of NENs with PM was organized according to disease grade and symptom profiles. In grade 1 and 2 well‐differentiated NENs, cytoreductive surgery received strong support (>95%) after the management of functional syndromes (if present). For grade 3 well‐differentiated NENs, systemic therapy is the primary recommendation, with surgical resection considered in select cases. Given the limited evidence, the consensus‐driven clinical pathway offers vital clinical guidance for the management of NENs with PM. The need for high‐quality evidence remains critical to the field.

Background/Objectives: Overall survival for patients with Stage 3 pancreatic ductal adenocarcinoma (PDAC) remains limited, with a median survival of 12 to 15 months. Irreversible electroporation (IRE) is a local tumor ablation method that induces cancerous cell death by disrupting cell membrane homeostasis. The DIRECT Registry study was designed to assess the effectiveness and safety of IRE when combined with standard of care (SOC) treatment for Stage 3 PDAC versus SOC alone in a real-world setting after at least 3 months of induction chemotherapy; Methods: Patients with Stage 3 PDAC treated with IRE plus SOC or SOC alone were prospectively enrolled in a multicenter registry study. Enrollment required 3 months of active multi-agent chemotherapy with no progression before enrollment. Endpoints were 30- and 90-day mortality and adverse events (AEs). Results: Eighty-seven IRE and 27 SOC subjects were enrolled in the registry. Mean ages were 64.0 ± 8.4 and 66.4 ± 9.9 years, and mean anterior/posterior tumor diameters were 2.2 ± 0.7 cm and 3.2 ± 1.3 for the IRE and SOC groups respectively (p = 0.0066). All IRE procedures were performed using an open approach. The 90-day all-cause mortality was 5/83 (6.0%) and 2/27 (7.4%) for the IRE and SOC groups, respectively. Two subjects in the IRE group died from treatment-related complications, and one patient in the SOC group died due to chemotherapy-related complications. Conclusions: Initial results from the DIRECT registry study indicate the use of IRE for curative intent tumor ablation in combination with induction chemotherapy has equivalent morbidity and mortality rates when compared to standard-of-care chemotherapy alone.

e16301 Background: Outcomes for patients with Stage 3 pancreatic ductal adenocarcinoma (PDAC) remain poor with a mean overall survival (OS) of 11 months. Irreversible electroporation (IRE) is a method of local tumor ablation that causes cell death by disrupting homeostasis in the cell membrane. Previous research suggests IRE can be useful in the multi-disciplinary treatment of Stage 3 PDAC. The present study was designed to assess the effectiveness and safety of IRE for Stage 3 PDAC in a real-world setting after induction chemotherapy. Methods: Patients with Stage 3 PDAC treated with IRE were prospectively enrolled in a multicenter registry study. Enrollment required 3 months of active multi-agent chemotherapy, with no progression before IRE treatment. Endpoints were 30- and 90-day mortality from enrollment and the new onset of an adverse event (AE). Results: 87 patients were enrolled in the registry between May 2019 and May 2023. Mean age was 64.0 ± 8.4 years, 57.5% were female and mean tumor diameter was 2.2 ± 0.7 cm. Mean time from diagnosis to IRE treatment was 8.9 ± 4.9 months. All subjects underwent induction chemotherapy with the most common being FOLFIRINOX alone, gemcitabine with albumin-bound paclitaxel, or a combination of both in 47 (54.0%) patients. Thirty-seven (42.5%) patients had prior radiation therapy. All procedures were performed using an open approach with 50 (57.5%) for in-situ tumor ablation and 37 (42.5%) with the intent of margin accentuation in combination with resection. Major adjunctive procedures were performed for 70 (80.5%) patients. Common adjunctive surgeries were cholecystectomy (33.3%), Whipple procedure (28.7%) and either distal or subtotal pancreatectomy (11.4%). Mean IRE delivery time was 55.7 ± 54.5 minutes with an average of 3.1 probes (range 2 to 6) used per procedure. There was a mean of 1031.1 ± 882.1 pulses delivered per procedure. The 30- and 90-day mortality was 3/87 (3.4%) and 4/82 (4.9%) respectively. There were 21 (24.1%) patients who developed AEs related to IRE treatment during the 90-day post-procedure period (9 patients had AEs that were definitely related to IRE, 5 probably and 7 possibly). Of these related events, only three were Grade 4 or higher (arterial hemorrhage, cardiac arrest, and septic shock). Overall, gastrointestinal related AEs were the most common representing 16 of the 28 (57.1%) of all AEs associated with the IRE procedure. One patient died within 30 days of the procedure due to an intraperitoneal arterial hemorrhage that was deemed to be definitely related to the IRE treatment. Conclusions: The use of IRE for curative intent tumor ablation alone or in combination with resection following induction chemotherapy in patients with locally advanced Stage 3 PDAC has acceptable safety and is associated with acceptable morbidity and mortality rates in appropriately selected patients. Clinical trial information: NCT03899649 .

TPS276 Background: Immune checkpoint inhibitors have revolutionized the treatment of a number of cancers. In colorectal cancers, their efficacy is limited to mismatch repair deficient or microsatellite stability-high (dMMR/MSI-High) tumors only. These constitute only 4-5% of all metastatic colorectal cancers (mCRC). Novel approaches are needed to make immunotherapy a viable option for mismatch repair proficient or microsatellite stable (pMMR/MSS) tumors. Increasing exposure of neo-antigens to the immune system could be one potential strategy to enhance the response of immunotherapy. Yttrium 90-radioembolization (Y90-RE) in combination with immunotherapy may work synergistically to enhance efficacy of each other. Additionally, radiation can potentially make the tumor microenvironment conducive to effector T-cell recruitment and function. Therefore, we hypothesize and propose the clinical trial of combining immunotherapy with Y90-RE as a feasible and safe strategy that will improve outcomes in patients with mCRC with liver-predominant metastases. Methods: This clinical trial will be conducted as a single-center, open-label, Phase I/II trial to evaluate initially the feasibility and safety of Y90-RE in combination with a fixed dose of immunotherapy (durvalumab) in subjects with liver-predominant, mCRC (Table). It will be offered in the refractory setting. The trial will be performed in 18 subjects with mCRC with liver metastasis and the safety of immunotherapy (durvalumab) with Y90-RE will be investigated in an accelerated titration design. This would allow a maximum tolerated dose with the minimum number of subjects. Correlative studies pertaining to serial circulating tumor DNA (ctDNA - liquid biopsies) testing as well as immune-panel based profiling will be performed alongside pre- and post-biopsies to study changes in the tumor microenvironment. Clinical trial information: NCT04108481. [Table: see text]

763 Background: Non-invasive biomarkers with high sensitivity and specificity would be of great value for patients with Pancreatic Ductal Adenocarcinoma (PDAC). This would aid in early detection and serve other purposes that 'liquid biopsies' are being explored in. Besides circulating tumor DNA (ctDNA) and methylation markers, glycosylation markers hold great potential promise. We developed a novel workflow using high-resolution quantification of site-specific protein glycosylation by liquid chromatography and tandem mass spectrometry to evaluate the clinical utility of glycoprotemics signature for patients with PDAC. Methods: Serum samples from newly diagnosed PDAC patients and controls were obtained from a commercial biobank (Indivumed, Hamburg, Germany), and a panel of 504 glycan motifs, representing 73 previously reported proteomic markers, was determined. Age-adjusted generalized linear regression models were used to evaluate the differential abundance of each marker, and stepwise variable selection was used for model construction. Results: We analyzed 45 PDAC and 136 control samples. PDAC patients (60% male) had a mean age of 67 (±11) years. with 4.4%, 71.1%, 4.4%, and 20% at stage 1, 2, 3,4, respectively. Controls were women with benign histology after pelvic mass surgery; with a mean age of 61 (±11) years. Twenty-six glycoproteomic markers showed statistically highly significant differential abundance among cases and controls (p<1e-4 each) and were highly reproducible(Pearson’s r > 0.85), which were glycoforms in proteins that have previously been found to be associated with PDAC. Fourteen of these markers displayed >0.8 area under the curve of the receiver operating characteristic (AUC). Multivariate logistic regression modeling with backward selection yielded a classification model with an AUC of 0.94 (95% CI: 0.89-0.99), sensitivity of 91% (95% CI: 75-97%) and specificity of 86% (95% CI: 81-92%). Conclusions: Circulating glycoproteomic biomarkers may be useful in the early detection and clinical management of PDAC patients; offering a new platform to explore and validate.