Citations

Abstract Background An accurate discrete spot scanning (DSS) beam delivery time (BDT) model is essential, particularly as 4D dynamic dose accumulation calculations rely on machine‐specific time models for reliable interplay evaluation. Purpose To derive a BDT model for a synchrotron‐based Hitachi Probeat PBS proton system from oscilloscope measurements of key BDT structures, including multi‐energy extraction (MEE) characteristics. Methods Key BDT structures were characterized using oscilloscope measurements, supplemented by delivery log files where appropriate. Spot‐to‐spot scanning trajectories were visualized using a CROSSmini 2D strip ionization chamber (Liverage Biomedical Inc, Taiwan) via the dose‐driven continuous scanning (DDCS) mode. The MEE design and MEE charge recapture efficiencies were also characterized. In addition, the impact of the number of delivered spots on both the extractable fraction of charge and MEE recapture efficiency was investigated. Results An improved synchrotron‐based BDT model was derived that incorporates dead times between radiofrequency knockout (RFK) and high‐speed steering magnet (HSST) signals. Spot‐to‐spot movement follows a “hockey‐stick”‐like behavior where the effective spot‐to‐spot move time is governed by the slower axis. An energy‐dependent variation in the number of MEE layers deliverable per spill was also observed, with fewer MEE layers per spill (1–3) was observed in low and high energy ranges compared to the mid‐energy range (4–5), deviating from the nominal vendor value of five MEE layers per spill per block. A reduction in the extractable fraction of charge was observed with an increasing number of spots per spill, while increasing the number of delivered spots in the preceding layer significantly reduced the MEE recapture efficiency. Conclusion MEE characteristics should be incorporated into synchrotron‐based time models for accurate beam delivery modeling. The methodology presented here also provides a framework for centers seeking to derive machine‐specific delivery time models for their proton systems.

Abstract Recent single-cell transcriptomic studies of follicular lymphoma (FL) have revealed heterogeneity among malignant B (MB) cells and selected components of the tumor microenvironment (TME), but have been constrained by relatively small sample sizes and a lack of spatial context. We performed comprehensive cellular profiling and spatial dissection of over five million cells by integrating single-nucleus RNA sequencing (snRNA-seq) from 182 samples (FL, n = 167; control, n = 15) with single-cell spatial transcriptomics (ST) from 386 samples (FL, n = 365; control, n = 21). After stringent quality control, 1,289,073 and 3,968,427 cells from snRNA-seq and ST data, respectively, were analyzed. Unsupervised clustering of snRNA-seq data identified 58 TME cell subtypes. To extend this classification to the ST dataset, we integrated snRNA-seq and ST data by co-embedding them into a shared principal component space, enabling robust batch correction and cell-type label transfer across modalities. Using this supervised annotation framework, ST data recapitulated 54 TME cell subtypes. MB, proliferating MB (MBprolif), and healthy B (HB) cells were classified using sample-level unsupervised clustering in ST. Macrophages exhibited previously uncharacterized heterogeneity in transcriptomic profiles and spatial distribution. We identified CXCL13-expressing macrophage subtypes with high intra- and peri-follicular abundance, termed follicular macrophages (FMs). Non-negative matrix factorization of intrafollicular cell fractions identified five TME archetypes: FM, follicular stroma, two follicular T, and HB archetypes. The FM archetype was enriched for intrafollicular macrophages, including FMs, and showed a significantly higher proportion of grade 3A/3B cases (53.4%) compared to other archetypes (≤16.5%). It was also associated with a higher frequency of high tumor burden requiring treatment initiation rather than a watch-and-wait (WW) approach. Among patients managed by WW, those with the FM archetype showed significantly shorter event-free survival (EFS) compared to those with non-FM archetypes, whereas this association was not observed among treated patients. The percentage of intrafollicular macrophages (IFMP) showed excellent predictive performance for the FM archetype (area under the curve: 0.90). IFMP calculated in a published multiplex spatial protein imaging dataset from an independent cohort of 242 FL patients validated the associations between high IFMP and both pathology grade 3A/3B and shorter EFS in WW patients. Consistently, spatial neighborhood and cell–cell communication analyses revealed co-localization of FMs and MBprolif cells, forming a distinct niche with activated signaling mediated by FM-derived CXCL13, APRIL, and BAFF. Our integrative multi-modal analysis defines previously unrecognized cellular heterogeneity and spatial architecture in FL and highlights macrophage-enriched follicular ecosystems associated with aggressive clinicopathological features, providing a framework for improved biological understanding and patient management. Citation Format: Yoshiaki Abe, Bijal Thakkar, Atish Kizhakeyil, Ashley Wilson, Andrew L. Feldman, Jared Henderson, Amy Ayers, Sara Borgschatz, R. Andrew Harkins, Priya Lakra, Daisuke Kaji, Jonathon B. Cohen, David Russler-Germain, Eric Mou, Francisco Vega, Jennifer Chapman, Giorgio Inghirami, Carla Casulo, Izidore S. Lossos, Jean L. Koff, Chijioke Nze, Peter Martin, Sergei Syrbu, Kiran Vij, David L. Jaye, James R. Cerhan, Christopher R. Flowers, Anne J. Novak, Richard Burack, Dai Chihara, Mamiko Sakata-Yanagimoto, Joshua Tobin, Xubin Li, Michael R. Green. Spatially resolved microenvironment profiling reveals distinct follicular lymphoma archetypes [abstract]. In: Proceedings of the Fifth AACR International Meeting on Advances in Malignant Lymphoma: From Discovery to Clinical Impact; 2026 Jun 24-27; Philadelphia, PA. Philadelphia (PA): AACR; Blood Cancer Discov 2026;7(3_Suppl):Abstract nr A049.

Abstract Background: Although some vaccines seem to be associated with a lower risk of lymphoma, their impact on outcomes is largely unknown. Methods: Data from a large prospective lymphoma cohort study were utilized to estimate associations of self-reported history of vaccination against hepatitis A, hepatitis B, influenza, and yellow fever with event-free survival (EFS) and overall survival (OS) using Cox proportional hazard models. Results: None of the vaccines were associated with EFS [hazard ratio (HR) 0.77–1] or OS (HRs 0.96–1.04). Similarly, there were no significant associations between the vaccines and outcomes for each lymphoma subtype. Conclusions: Prior vaccination against selected viruses was not associated with EFS or OS among patients with lymphoma. Impact: We did not find evidence for an impact of prior vaccination on lymphoma prognosis.

Précis: Glaucoma patients of similar age and educational level, compared with healthy individuals, exhibit a greater number of saccades and fixations during eye-tracking-aloud reading, resulting in reduced reading speed. Purpose: To evaluate reading performance in patients with glaucoma compared with controls using an eye tracker and to explore the potential confounding effects of patients’ contrast sensitivity and cognition. Materials and Methods: A cross-sectional study was conducted with 111 participants (57 with glaucoma and 54 controls) with a best-corrected visual acuity of ≥0.5 logMAR. Cognition was assessed using the Montreal Cognitive Assessment, and contrast sensitivity was measured with the Freiburg Visual Acuity and Contrast Test. A reading performance evaluation was conducted using the Minnesota Low Vision Reading Test displayed on slides on a computer screen. Reading speed was calculated in words per minute, and an eye tracker was used to analyze saccade and fixation patterns during the reading task. Results: Mean age was 61.8 (±11.6) and 66.5 (±13.7) in the glaucoma and control groups, respectively ( P =0.05). Best-corrected visual acuity was 0.18 (±0.16) and 0.04 (±0.10) logMAR in the glaucoma and control groups, respectively ( P <0.001). Montreal Cognitive Assessment score was 21.8 (±3.5) in the glaucoma and 21.4 (±4.0) in the control group ( P =0.566). A total of 26% of the glaucoma group and 33% of the control group had at least a primary education. Controls read faster and showed fewer saccades and fixations than patients with glaucoma ( P <0.05) across all 5 slides. Conclusions: Patients with glaucoma exhibit poorer reading performance, as evidenced by eye-tracking data, compared with controls of similar age, cognitive function, and educational level.

Endometriosis is a chronic inflammatory condition affecting 10% to 15% of reproductive-aged women. The urinary tract is the second most common extragenital site of endometriosis after the gastrointestinal tract, with a prevalence of 15% to 50% of women with deep endometriosis (DE). The urinary bladder is the most common site of urinary tract involvement (85%), followed by the ureter (10%), kidney (4%), and urethra (2%). Urinary bladder (anterior compartment) and ureter (mediolateral compartment) involvement are considered different disease entities. Patients with bladder involvement are more symptomatic with dysuria, urinary frequency, and recurrent urinary tract infections. Ureteral involvement is more commonly due to extrinsic compression, but may be intrinsic, involving the ureteral mucosa or muscularis. Hematuria is a rare presenting symptom of both bladder and ureteral involvement. Malignant transformation of urinary tract endometriosis is rare; however, DE involvement of the urinary tract may be mistaken for malignancy. Radiologists need a high index of suspicion for endometriosis in reproductive-aged women, and recognition of urinary tract involvement is important for timely treatment.

Abstract Histopathological assessment has served as the gold standard for diagnosing Alzheimer’s disease (AD). Emerging technological advancements, including the development of amyloid positron emission tomography (PET), have enabled early detection of amyloid pathology, one of the neuropathological hallmarks of AD. Genome-wide association study (GWAS) across cohorts of aging and AD, leveraging different measurements of amyloid burden, may facilitate the identification of novel genetic variants that drive the earliest neuropathological changes in AD. This study presents the largest GWAS of brain amyloidosis to date, leveraging amyloid β (Aβ) measured by in vivo amyloid PET and postmortem histopathology from 13,555 individuals of European ancestry. Amyloid positivity was defined as moderate or frequent neuritic plaques according to the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) staging scores for each postmortem cohort. A Gaussian mixture model (GMM) was applied to each amyloid PET cohort to identify the cohort and tracer-specific cut-offs that differentiate amyloid positive and negative populations. In silico and ex vivo analyses further characterized implicated loci, including interrogating the association between bulk and single-nucleus gene expression profiles and AD-related traits. Genetic covariance analysis assessed the extent amyloid PET and postmortem measures reflect the shared genetic architecture of brain amyloidosis. Our combined amyloidosis GWAS identified three established AD risk loci: BIN1 (rs6733839, OR = 1.20, 95% CI 1.14-1.26, P = 1.32 × 10−11), CR1 (rs4844610, OR = 1.24, 95% CI = 1.16-1.32, P = 4.21 × 10−10), APOE (rs429358, OR = 4.01, 95% CI = 3.66-4.38, P = 4.54 × 10−201), and a newly identified brain amyloidosis-associated variant on chromosome 17 (rs35635959, OR = 1.18, 95% CI = 1.12-1.25, P = 1.47 × 10−8). SuSiE fine-mapping identified a single credible set of 15 putative causal variants with rs35635959 as the lead variant. Subsequent eQTL and SuSiE-based colocalization analyses prioritized rs35635959 as a strong eQTL for TUBG2, encoding tubulin gamma 2, which is involved in microtubule organization and synaptic plasticity. Further cell-type-specific characterization of this gene in neurons from dorsolateral prefrontal cortex tissue indicated that decreased TUBG2 expression was associated with increased Aβ burden and AD case status (PFDR &lt; 0.045). Furthermore, our study is the first to report a modest genetic covariance (covariance=0.17, P &lt; 6.54 × 10−8) between the genetic architecture of amyloid burden captured by different modalities. While APOE showed a strong association with both amyloid endophenotypes, the observed genetic covariance was not substantially attenuated after excluding variants within the APOE region (covariance=0.16, P &lt; 1.32 × 10−7). Our results highlight the benefits of leveraging compatible, harmonized AD endophenotypes to increase power to uncover new molecular insights into the etiology of AD neuropathology. Wang et al. present the largest GWAS of brain amyloidosis to date, analysing 13,555 individuals using amyloid PET and postmortem Aβ measures. They identify a novel amyloidosis-associated variant on chromosome 17, demonstrate genetic covariance between modalities, and highlight complex traits sharing genetic architecture with Aβ burden.

Through a Delphi process, all 33 panelists reached consensus on topics relating to MRI reporting of knee meniscus lesions, demonstrating that interdisciplinary and multi-institutional standardization is possible.

Abstract Background Inflammatory bowel disease (IBD) can lead to a hypercoagulable state, particularly at initial diagnosis. Consequently, venous thromboembolism (VTE) represents a serious complication associated with IBD. For children, the risk of VTE near the time of IBD diagnosis has not yet been quantified, and guidance for VTE prophylaxis remains unclear. Methods This multisite matched case-control study examined pediatric patients with a new diagnosis of IBD from 2019-2024. Cases were those who developed VTE ≤30 days prior or ≤90 days post IBD diagnosis. Controls were newly diagnosed IBD patients without VTE. Each case was matched to 2-6 controls based on IBD subtype and age at IBD diagnosis. Demographics, laboratory values, prothrombotic risk factors and treatments were compared between matched cases and controls using conditional logistic regression stratified, by case sets. Results Study subjects included 15 cases and 52 controls, resulting in 70 matched pairs. Factors associated with early VTE included lower hemoglobin (P = .003), lower albumin (P = .002), corticosteroids use (P = .01), central line (P = .002), and any surgery ≤90 days post IBD diagnosis (P = .001). No association with VTE was detected for platelets, C-reactive protein, fecal calprotectin, family history of IBD or body mass index. Conclusions Albumin, hemoglobin, steroid use, central line, and any surgery ≤90 days post IBD diagnosis were associated with early VTE. These risk factors may be used in a future prediction model to stratify newly diagnosed pediatric IBD patients by their risk for early VTE development.