Citations

Abstract INTRODUCTION Anti—amyloid‐β (Aβ) therapies are reshaping Alzheimer's disease (AD) management. Understanding changes in real‐world patterns of diagnostic testing and infusion chair usage is essential for optimizing access to care. METHODS Retrospective analysis of Mayo Clinic enterprise electronic health records (Jan 2019–Mar 2025) assessed trends in AD‐relevant brain imaging, fluid biomarkers, apolipoprotein E (APOE) testing, and lecanemab infusions. Rates of amyloid‐beta (Aβ) positivity by sex and age, APOE genotype frequencies, and lecanemab treatment initiation and discontinuation were evaluated. RESULTS Following national insurance coverage changes, lecanemab infusions grew by 110 infusions per quarter to 605 in Q1 2025. Aβ positron emission tomography scans increased (+22/quarter), cerebrospinal fluid biomarker orders declined (−25/quarter), and plasma p‐tau 217 orders rapidly increased (+238/quarter). Females were more likely to be Aβ positive ( p < 0.006). APOE ‐ε4 homozygotes were less likely to initiate lecanemab (HR = 0.11, p < 0.001). DISCUSSION The adoption of anti‐Aβ therapies coincided with a rapid shift in diagnostic workflows.

Abstract Modern radiation therapy (RT) technologies allow for improved sparing of normal tissues, decreasing the risk of both acute and long-term toxicities. Existing RT dose constraints for prospective trials within the National Clinical Trials Network (NCTN) were formulated in the context of solid malignancies. As patients with hematologic malignancies are often treated with lower RT doses and are usually younger with more favorable prognoses, customized dose constraints are needed. The NRG Oncology Hematologic Malignancies Working Group (NRG HEME) commissioned a review of existing organ-at-risk (OAR) constraints from published primary literature, the NRG Center for Innovation in Radiation Oncology (CIRO), and national guidelines. Customized constraints were developed by iterative review by NRG HEME. Final recommendations were approved by radiation oncology representatives from all the lymphoma NCTN groups (NRG Oncology, Children’s Oncology Group, Alliance, ECOG-ACRIN, SWOG, Canadian Cancer Trials Group). For 49 OARs, a strict recommended constraint was determined, of which 20 were not present in CIRO. Of the remaining 29 constraints, 20 were lower, 2 were the same, and 5 used different metrics; 2 were higher than at least 1 CIRO trial constraint. Acceptable variations were determined and unacceptable variations were added for select critical OARs for plan scoring. While doses to OARs without explicit unacceptable variations should not exceed acceptable variations, violations should not be considered for plan quality assessment on trials. This consensus list of standard OAR constraints should be incorporated for all future NCTN trials in hematologic malignancies. Strict dose constraints will minimize long-term toxicities in this patient population.

Abstract Introduction The evaluation of diastolic function in diabesity patients undergoing incretin-based therapy could facilitate early detection and help prevent progression to heart failure. Methodology A group of 15 diabesity cases with chest x-ray examinations (< 1 month) before and after ≥ 12 months of incretin-based therapy (absent ventricular/valvular dysfunction) were identified. Standard diabesity descriptors and predictions of pulmonary venous hypertension (aka “pulmonary congestion”) [None; Stage 1: vascular distention/redistribution but minimal interstitial edema; or Stage ≥ 2: vascular congestion with ≥ mild interstitial or alveolar edema] by validated AI-enabled chest x-ray staging, representing mean left atrial pressure in diastolic dysfunction, were evaluated pre- and post-therapy. Results By weight loss, cases clustered into equal-sized subgroups: 1. Significant Responders (9–30% decreases); 2. Insignificant Responders (0–2% decreases); and 3. Non-Responders (2–12% increases). Regarding hemoglobin A1c changes: 1. Significant Responders collectively decreased; 2. Insignificant Responders varied; and 3. Non-Responders were largely stable. Pre-therapy, all 15 cases demonstrated AI-enabled chest x-ray evidence of diastolic dysfunction; post-therapy, 4 improved (especially cases of greatest weight loss or hemoglobin A1c reduction), 5 were stable, and 6 worsened. Per subgroup, AI-enabled chest x-ray indications therapeutic response were: 1. Significant Responders (all demonstrating unequivocally decreased obesity and improved diabetes) collectively showed stable-decreased dysfunction; 2. Insignificant Responders (all demonstrating minimally decreased obesity but stable-worsening diabetes in most) reflected stable-increased dysfunction in 60%; and 3. Non-Responders (all demonstrating increased obesity but stable-improved diabetes) showed increased dysfunction in 80%. Conclusion AI-enabled CXR staging detects background subclinical diastolic dysfunction in diabesity and monitors its response to incretin-based therapy.

Abstract Peritoneal Carcinomatosis (PC) is a metastatic cancer of the lining of the abdominal cavity, most often originating from the gastrointestinal or gynecological tracts. PC occurs in approximately 20% of colorectal cancer and 60% of ovarian cancer cases, with estimated 5-year survival rates as low as 6%. Pressurized intraperitoneal aerosolized chemotherapy (PIPAC) is a locoregional drug delivery modality administered via a minimally invasive laparoscopic approach. PIPAC shows promise in the treatment of peritoneal metastasis in early trials on colorectal cancer (CRC) or appendiceal cancer (AC) in patients who cannot undergo cytoreductive surgery. The spatial organization of the tumor microenvironment (TME) and the complex cellular interactions within profoundly shape biology and treatment response. Spatial transcriptomics offers an opportunity to characterize TME heterogeneity in its native architecture, allowing the identification of biomarkers, interactions, and gene expression programs as well as resistance mechanisms and new potential targets. We performed image-based spatial transcriptomic profiling of 152 tissue samples, including 50 pre-treatment and 65 post-treatment metastatic tumors and 17 pre-treatment and 20 post-treatment tumor-adjacent normal tissue samples from 19 patients who participated in a Phase I trial on Oxaliplatin PIPAC. Through a comprehensive characterization of transcriptional profiles of a total of 1,249,711 cells, as well as cellular neighborhood and ligand-receptor interactions, we describe the heterogeneity of PC in its spatial context. We have further characterized treatment-driven changes in pre- and post-treatment tumors of a subset of 7 patients who underwent PIPAC with mitomycin IP. Through cell-based niche and proximity analyses, we identify distinct shifts in the composition and architecture of treated tumors. Most notably, treatment resulted in an 87% decrease in the number of malignant cells, as well as an expansion of the plasma-barrier niche and an increased number of immune infiltrates. Further analysis revealed distinct differences in the abundance of specific cancer-associated fibroblast and immune subsets, demonstrating changes in TME architecture. Overall, our results provide an invaluable characterization of PC in CRC and AC, garnering new insight into their architecture, cellular composition, and cell-cell interactions at baseline and in response to regional chemotherapy. Further analyses and follow-up studies can identify and validate new, actionable biomarkers to target these hard-to-treat tumors. Citation Format: Heini Maaret Natri, Arianna L. Williams-Katek, Muhammad Talha Waheed, Tiana Li, Marwan Fakih, Mingye Feng, Amit Merchea, Sue Chang, Richard L. Whelan, Danielle Deperalta, Thanh H. Dellinger, Nicholas Banovich, Mustafa Raoof. Spatial transcriptomic profiling of peritoneal metastases identifies multicellular programs in patient tumors undergoing pressurized intraperitoneal aerosol chemotherapy (PIPAC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 3958.

Abstract Introduction Revascularization to prevent limb loss is not feasible or represents a very high risk in a significant proportion of patients with chronic limb-threatening ischaemia (CLTI). No standard definition currently exists to define this population of patients. The aim of this study was to develop a consensus-based, multidomain definition to improve clinical assessment and reporting of studies in people with ‘no option’ (NO) or ‘poor option’ (PO) CLTI. Methods A modified Delphi process was conducted with 164 specialists from 30 countries. Two iterative survey rounds were used to reach consensus, defined as ≥70% agreement with a score of ≥7 on a nine-point scale. Results Some 164 international vascular specialists participated in the study, averaging 19 years of experience. A multidomain framework including arterial disease anatomy, biology, risk, function, and context (ABRFC) achieved 83% consensus. A ‘desert foot’ was defined as the absence of distal arterial revascularization targets on advanced non-invasive imaging, invasive digital subtraction angiography, and at least one failed endovascular revascularization attempt (81.6% agreement). Inadequate autogenous bypass conduit was defined as the lack of usable autologous vein across all four limbs (85% agreement). Patients were classified as NO for revascularization if they present with ‘desert foot’, prohibitive medical risk, a non-functional limb, or in those patients who refused arterial revascularization. PO revascularization patients combined factors such as severe infection, lack of autologous vein, or treatment non-compliance (72.1% agreement). Conclusion This consensus study established a structured, expert-validated definition of no option or poor option for revascularisation of patients with CLTI. The multidomain ABRFC framework provides a foundation for standardized clinical assessment, trial design, and future guideline development.

Abstract Background: Aberrations in telomere length have important implications in cancer development and progression. This study aimed to determine whether leukocyte telomere length (LTL) in patients with colorectal cancer (CRC) is associated with survival outcomes. We also investigated whether genetic variants in telomere maintenance genes are associated with survival in these patients. Methods: Blood specimens were collected from 1,007 patients prior to receiving chemotherapy or radiation. Genomic DNA was extracted using the Promega Maxwell RSC instrument. LTL was measured in triplicate using monochrome multiplex PCR, where the average amplification value of telomeric repeats was termed T. Similarly, PCR amplification of a single-copy reference gene was performed, and its average amplification value was termed S. The telomere length for each sample was expressed as the T/S ratio. Genotyping of single-nucleotide polymorphisms (SNPs) in TERC, TERT, and OBFC1 genes was conducted at the institutional Genome Analysis Core facility. Kaplan-Meier survival curves were generated to evaluate patient survival outcomes. Results: Younger individuals (∼25 years) exhibited nearly a twofold longer LTL compared with older individuals (∼75 years). No significant difference in LTL was observed between stage II and stage III CRC patients. A strong inverse correlation was observed between patient age and LTL (Spearman’s r = -0.48; p = 1.13 × 10-58). Females had significantly longer LTL than males (p = 3.97 × 10-5). The TERC SNP rs1317082 was significantly associated with both overall survival (OS) and disease-free survival (DFS) in the combined stage II and stage III patient cohort (p = 0.017 and p = 0.023, respectively). Similarly, the OBFC1 SNP rs9419958 was significantly associated with OS (p = 0.016). Importantly, LTL itself was significantly associated with both OS and DFS (p = 0.008 and p = 0.044, respectively) among the combined stage II and stage III patients. Kaplan-Meier survival analyses demonstrated that age- and sex-adjusted LTL was predictive of long-term survival outcomes. Conclusions: Survival among patients with stage II and III colorectal cancer is significantly influenced by LTL. Additionally, specific allelic variants of telomere maintenance genes, including TERC and OBFC1, are independently associated with improved survival, irrespective of LTL. These findings suggest that peripheral blood LTL measurement, along with telomere-related genotyping, may serve as a valuable prognostic marker for colorectal cancer outcomes. Funding: Individualizing colorectal cancer patient care using the host and tumor telomere phenotype (RO1 CA204013), Curtiss Fund (92541775), C-SiG Core(s): Epigenomics & Spatial Biology Core, and Clinical Core of the Mayo Clinic Center for Cell Signaling in Gastroenterology (P30DK084567) Citation Format: Estela M. Cruz Garcia, Gobinda Sarkar, Jun Chen, Shubham Sood, Kim Kossick, Daniel Schupack, Rondell Graham, Brooke Druliner, Zahra Heydari, Lauren Helgeson, Richard G. Cawthon, Lisa A. Boardman. Longer leukocyte telomeres and specific alleles of telomere maintenance genes are independently associated with improved survival of colon cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 1919.

Abstract Introduction: Ewing sarcoma (EwS) is a FET::ETS family member-driven primary bone cancer demonstrating vast heterogeneity. Between a patient’s primary diagnosis and disease progression, tumor cell state adaptation, microenvironment changes, and the landscape of evolving therapeutic vulnerabilities remain poorly understood. To address these gaps, the Sean Karl Cohort was established in 2025 to conduct the largest single-cell transcriptomic analysis of retrospective paired tumor samples from patients with EwS. Here, we present data from the five analytic teams, and through shared SOPs now expand this cohort to Europe. Methods: Common sample processing SOPs were established to isolate cells from FFPE material from paired patient EwS samples. Single-cell (sc) RNAseq was generated using the GEM-X Flex Gene Expression protocol (10x Genomics). Alex’s Lemonade Stand Foundation (ALSF) Data Lab established a common data processing and integration pipeline with an EwS-specific cell annotation workflow to create a harmonized dataset for downstream analyses. Analytic teams were created to define tumor cell subpopulations and their therapeutic vulnerabilities and to characterize the tumor microenvironment. Data: We demonstrate the feasibility of generating high-quality scRNAseq profiles from retrospective FFPE-preserved EwS tumors. To date, 116 samples have yielded ∼800,000 cells. Integrated analysis reveals reproducible EwS tumor cell states shared across patients with regulatory network analyses nominating candidate therapeutic vulnerabilities. The scale of this international cohort enables saturation analysis for rare cell populations. Paired and longitudinal samples further allow correlation of emergent cell states with therapy resistance and metastatic progression. For example, immune-focused analyses show increases in T cell and macrophage populations in post-therapy samples. A novel, standardized EwS-specific cell annotation workflow has been developed to harmonize analyses and findings. These data will be openly shared with the community through the ALSF Single-cell Pediatric Cancer Atlas Portal. Conclusion: Large-scale international collaborative sample sharing, standardized processing pipelines, and harmonized EwS-specific annotations now enable deep single-cell analyses to characterize tumor heterogeneity in this rare pediatric and adolescent cancer. An in vivo expansion of the Sean Karl Cohort is underway to assess conservation of EwS tumor cell states and regulatory vulnerabilities identified in human tumors pre- and post-therapy in preclinical models, further supporting translation of these findings toward therapeutic strategies. Citation Format: Abbe Pannucci, Elina Mukherjee, Jessica D. Daley, Shireen Sita Ganapathi, Elissa Boguslawski, Lea Surrey, Lauren Gutstein, Patrick Azar, Emily Stockfisch, Azfar Neyaz, Ivy John, Jennifer Picarsic, Yutaro Tanaka, Byron Butaney, Riaz Gillani, Brian D. Crompton, Katherine A. Janeway, Jaclyln Taroni, Jessica Davis, Damon Reed, Adam Shlien, Theodore W. Laetsch, Rajen Mody, Clémence Henon, Thomas G. Grünewald, Elizabeth R. Lawlor, Filemon Dela Cruz, Patrick J. Grohar, Jovana Pavisic, Ally Hawkins, Anthony R. Cillo, Kelly M. Bailey. The Sean Karl Cohort: An international single-cell RNAseq study of paired patient Ewing sarcoma specimens [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 643.

ABSTRACT Objectives To characterize the structure, resources, and educational practices of temporal bone laboratory training across ACGME‐accredited U.S. otolaryngology residency programs. Methods A national cross‐sectional survey was distributed to program directors and faculty responsible for temporal bone education. Survey domains included curriculum structure, training frequency, faculty involvement, assessment practices, and access to laboratory resources. Descriptive statistics and univariable regression analyses were performed to explore associations between program characteristics and neurotology fellowship pursuit. Results Thirty‐seven programs responded (28.2%). Laboratory structure varied widely, including longitudinal (monthly or weekly) and condensed (annual or 2–3 courses/year) formats. Programs with longitudinal sessions reported more annual lab hours than condensed formats (median 42 vs. 16 h/year, p = 0.003). All programs had access to cadaveric temporal bones (mean 2.25 ± 1.13 bones per resident/year), though five reported fewer bones than residents. The mean drill‐to‐resident ratio was 0.59, with 10.8% reporting a 1:1 ratio. Formal performance evaluation was used by 43.2% of programs. On exploratory univariable analysis, longer otology rotation duration was associated with having at least one neurotology fellow within five years ( p = 0.025). Larger resident cohort size ( p = 0.048) and older laboratory instruments ( p = 0.043) were associated with producing more than one fellow. Conclusion There is substantial variability in temporal bone education across U.S. otolaryngology training programs. Programs differ in curricula, resources, and access to cadaveric and simulation‐based training. Standardization of core components may improve educational equity and training consistency. Level of Evidence N/A.

ABSTRACT Immune thrombocytopenia (ITP) is an acquired autoimmune disorder characterized by antibody‐mediated platelet destruction, often driven by long‐lived plasma cells (LLPCs) resistant to conventional therapies. While most patients respond to corticosteroids and intravenous immunoglobulin (IVIG), a subset develops life‐threatening refractory disease. In this case series, we describe three patients aged 39, 85, and 58 with life‐threatening, multi‐agent refractory ITP and platelet nadirs < 2 × 10 9 /L who failed corticosteroids, IVIG, and thrombopoietin receptor agonists (TPO‐RAs). Following salvage therapy with daratumumab, a monoclonal antibody targeting CD38, all three patients achieved rapid hematologic recovery, with platelet count normalization within 1 week. This accelerated response allowed for urgent clinical stabilization, including safe anticoagulation and surgical intervention. The efficacy of daratumumab likely stems from a dual mechanism: the depletion of CD38+ LLPCs and the immediate modulation of Fc‐receptor‐mediated platelet clearance. These observations suggest that CD38‐targeted therapy can bypass traditional treatment resistance to achieve near‐immediate remission in high‐complexity, high‐risk clinical settings. While these results are compelling, prospective clinical trials are warranted to define the long‐term safety, durability, and optimal dosing of anti‐CD38 therapies in refractory ITP populations.