Abstract Purpose: Circulating tumor fraction estimate (ctFE) is a machine learning–derived composite metric of circulating tumor DNA (ctDNA) burden. We hypothesized that pre-treatment and early on-treatment ctFE could robustly risk-stratify patients with locally advanced (LA) and oligometastatic non–small cell lung cancer (NSCLC) treated with radiotherapy (RT). Experimental Design: In a prospective phase II clinical trial (NCT03916419), 26 patients with unresectable stage IIB to IIIC NSCLC received magnetic resonance (MR)-guided hypofractionated chemoradiotherapy (chemoRT) followed by immunotherapy. Plasma ctDNA was profiled at baseline and mid-treatment (days 10–14) to derive ctFE and maximum variant allele frequency (Max VAF). A burden-based ctFE threshold derived from baseline samples was applied unchanged to mid-treatment samples and validated in two external cohorts: LA NSCLC treated with chemoRT (LA-RW; n = 94) and oligometastatic NSCLC treated with RT (OM-RW; n = 309). Results: Pre- and mid-treatment ctFE burden strongly stratified overall survival (OS) and progression-free survival (PFS), outperforming Max VAF and ctFE detectability. The baseline ctFE was prognostic for OS (HR 5.93, P = 0.005) and PFS (HR 11.08, P < 0.001) and remained significant at mid-treatment (OS: HR 7.08; PFS: HR 12.06; both P < 0.001). Early ctFE dynamics defined three molecular response groups with OS separation (median OS 60.8 vs. 13.0 vs. 2.9 months; P < 0.001). ctFE remained associated with survival in both validation cohorts. Conclusions: Early ctFE derived from a clinically available, tumor-naïve ctDNA assay enables noninvasive risk stratification in LA and oligometastatic NSCLC treated with RT, supporting its use as a practical biomarker for precision treatment adaptation.
Abstract TU118: Longitudinal Trajectories of Kidney Function in Heart Failure: A community study
Introduction: Chronic kidney disease affects nearly half of heart failure (HF) patients, underscoring the importance of regular kidney function monitoring. However, longitudinal trajectories of kidney function in HF are not well characterized. Identifying clinical factors linked to long-term changes is critical for improving monitoring and informing early clinical decisions. Hypothesis: We hypothesized that longitudinal kidney function and its associations with clinical variables in HF patients differ from that of demographically similar comparators from the same community. Methods: We analyzed patients with validated HF from a community-based cohort and comparators individually matched to age and sex selected from participants in the Mayo Clinic Biobank cohort. Individuals with end-stage kidney disease, dialysis or kidney transplantation prior to enrollment were excluded. Serum creatinine-based estimated glomerular filtration rate (eGFR) from outpatient and inpatient visits was assessed from enrollment for up to 10 years of follow-up. The median of eGFR for 90-day intervals was used to estimate the follow-up eGFR (Figure 1) . We modeled percentage change from baseline and fit linear mixed-effect models with time, HF status, and their interaction to test whether the eGFR trajectories differed between the two groups. In addition, we examined the association between eGFR trajectories and clinical variables. Results: We studied 1182 HF patients and 825 comparators with at least three eGFR measurements. Median follow-up was 5 years (IQR: 3-10) for HF patients and 8 years (6-9) for comparators. In total, 16245 serum creatinine measurements from HF patients and 9858 from comparators were analyzed. Median age at enrollment was 76 years (67-84) for HF patients and 78 years (70-83) for comparators. A greater decline in percentage change in eGFR was observed in HF patients (-4.23%, 95% CI: -4.75 to -3.70% per year) than in comparators (-1.90%, 95% CI: -2.51 to -1.29% per year; P<0.001, Figure 2 ). Among HF patients, the decline in percentage change in eGFR was greater in the presence of diabetes, hyperlipidemia, or a higher comorbidity burden. Conclusions: In this community study, HF patients exhibited a greater percentage decline in eGFR compared to community comparators. Among HF patients, eGFR decline was more strongly associated with comorbidities—particularly metabolic risk factors—highlighting the relevance of the cardiovascular-kidney-metabolic syndrome in HF.
Cognitive, biomarker, and neuroimaging indices associated with traumatic encephalopathy syndrome across two independent athlete cohorts
Abstract Background : Traumatic encephalopathy syndrome (TES) is a clinical research construct used to identify individuals at risk for chronic traumatic encephalopathy (CTE) following exposure to repetitive head impacts (RHI). Adjudication of TES relies on clinical features such as progressive cognitive impairment and neurobehavioral dysregulation. Blood-based biomarkers and structural neuroimaging abnormalities have been associated with TES but are not part of the criteria. This study evaluated whether TES identification was associated with the combined contribution of cognitive performance, blood biomarkers, and structural neuroimaging measures across two well-characterized cohorts. Methods : Participants included 158 professional fighters from the Professional Athletes Brain Health Study and 149 former American football players from The DIAGNOSE CTE Research Project. Three indices were constructed representing complementary domains: a cognitive index reflecting cohort-specific cognitive features, a blood biomarker index including plasma neurofilament light chain, glial fibrillary acidic protein, total tau, tau phosphorylated at amino acid 231, and APOE -ε4 carrier status, and an imaging index comprising volumetric MRI measures of subcortical structures, ventricles, and corpus callosum subregions. Grouped weighted quantile sum regression models were estimated within each cohort to evaluate associations between these indices and TES while adjusting for age, race, competition status, and RHI exposure. Results : Multidomain models demonstrated improved model performance compared with single-domain models in both cohorts (PABHS: AUC=0.91, PPV=0.80; DIAGNOSE CTE: AUC=0.84, PPV=0.85). Biomarker and imaging indices contributed additional information across cohorts, although imaging contributions were more prominent in fighters whereas blood biomarker associations were stronger in football players. Conclusion : TES in RHI-exposed athletes was associated with a convergent clinicobiological profile observed across two independent cohorts with distinct exposure patterns. These findings support multidomain analytic frameworks for evaluating correlated biological signals in RHI-exposed populations and may inform future studies of TES and CTE.
Drug Repurposing for Lung Disease: Mechanistic Rationale, Clinical Evidence, and the Path Forward
American Journal of Respiratory and Critical Care Medicine | April 25, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available
Background: In the last decade, a surge of advancements in and approvals of immunotherapies has revolutionized the treatment of non-small-cell lung cancer (NSCLC). Even as an increasing number of immune checkpoint inhibitors and antibody–drug conjugates gained FDA approval for the remarkable response and durable remission they imparted to some patients, persistent challenges of primary and acquired resistance, imperfect predictive biomarkers, and toxicity remain. Methods: This review identifies and summarizes the most significant emerging clinical data being reported for immunotherapies in NSCLC. Results: We found that the most recent clinical trials are centered on antibody–drug conjugates, bispecific and multispecific antibodies, cellular therapies, and immunocytokines, while other ongoing trials continue to explore new monoclonal antibodies as well as a variety of immunotherapy modalities. Conclusions: Immunotherapy in NSCLC remains an area of rapid advancement, with the potential for further improvements in safety and efficacy as monotherapy and in multimodal approaches.
Abstract LB418: RELATIVITY-104 Part 2: translational analyses in the programmed death ligand 1 (PD-L1) ≥ 1% and non-squamous (NSQ) non-small cell lung cancer (NSCLC) subgroup
Abstract Background: In Part 2 of the phase 2 RELATIVITY-104 study of first-line nivolumab (NIVO) plus relatlimab (RELA) with platinum-doublet chemotherapy (PDCT) vs NIVO + PDCT in patients with metastatic NSCLC, NIVO + RELA + PDCT demonstrated improved clinical benefit, including overall survival, in the prespecified subgroup of tumor PD-L1 expression ≥ 1%, which was further enriched in NSQ tumor histology. Baseline lymphocyte-activation gene 3 (LAG-3) expression was associated with enriched efficacy for both NIVO + RELA + PDCT and NIVO + PDCT. In a comparative transcriptomic analysis, NSQ and squamous tumors demonstrated distinct immune signatures, with NSQ tumors exhibiting higher expression of LAG-3 ligands and greater enrichment for combination therapy benefit by PD-L1 expression. To further elucidate the mechanism of action of NIVO + RELA + PDCT, we report additional exploratory translational data in the PD-L1 ≥ 1% NSQ subgroup for Part 2 of RELATIVITY-104. Methods: Patients with untreated metastatic NSCLC were randomized 1:1 to NIVO 360 mg + RELA 360 mg + PDCT or NIVO 360 mg + PDCT Q3W. Exploratory endpoints included translational analyses in the PD-L1 ≥ 1% NSQ subgroup. Gene expression data from pretreatment tumor RNA sequencing were normalized and analyzed for associations with clinical outcomes. Pre- and on-treatment peripheral blood samples were collected for high-dimensional flow cytometry immunophenotyping using a validated 24-marker LAG-3-specific panel that used drug-tolerant, noncompeting clones for LAG-3, PD-1, and CTLA-4. Statistical associations between biomarkers and clinical outcomes were assessed using logistic regression and Cox proportional hazards models. Data are from the May 2, 2025, database lock. Results: In the NIVO + RELA + PDCT arm, immune signatures demonstrated a significantly lower hazard ratio (HR) in the PD-L1 ≥ 1% NSQ subgroup, while stromal signatures demonstrated a significantly higher HR. T exhausted progenitor signature subsets, as well as ICOS+ CD4+ T cells, at baseline were shown to enrich for survival with NIVO + RELA + PDCT. Clinical benefit was observed across all baseline LAG-3 expression levels (< 1% and ≥ 1%); however, on-treatment increases in LAG-3+ T cells were associated with longer progression-free survival and a higher objective response rate with NIVO + RELA + PDCT. In the NIVO + PDCT arm, increases in LAG-3 cell populations were associated with lower response. Conclusions: In the RELATIVITY-104 study, the on-treatment immune dynamics of LAG-3+ T cells correlated with the benefit of NIVO + RELA + PDCT vs NIVO + PDCT in patients with PD-L1 expression ≥ 1% and NSQ NSCLC. Immune signatures including progenitor T exhausted signatures associated with improved outcomes with NIVO + RELA + PDCT. These data support the mechanistic rationale for adding anti-LAG-3 to anti-PD-1 + PDCT in PD-L1 ≥ 1% NSQ NSCLC. Citation Format: Jaclyn Neely, Annie Yu, Nicolas Girard, Manuel Cobo-Dols, Mauricio Burotto, Luis Paz-Ares, Vamsidhar Velcheti, Martin Reck, Srijata Samanta, Anila Qureshi, Priyanka Kasbekar, Charlie Garnett-Benson. RELATIVITY-104 Part 2: translational analyses in the programmed death ligand 1 (PD-L1) ≥ 1% and non-squamous (NSQ) non-small cell lung cancer (NSCLC) subgroup [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(8_Suppl):Abstract nr LB418.
Metabolomics of Right Ventricular Function in Pulmonary Hypertension
BACKGROUND: The metabolic mechanisms underlying right ventricular (RV) dysfunction are poorly understood, particularly outside of group 1 pulmonary hypertension (PH). We aimed to identify metabolites and pathways associated with RV systolic function and explored whether associations differed by pulmonary vascular resistance, PH group 1 status, and sex. METHODS: We analyzed data from the multicenter PVDOMICS (Pulmonary Vascular Disease Phenomics) cohort. RV systolic function metrics included fractional area change (echo), global longitudinal strain (echo), and ejection fraction (cardiac magnetic resonance). We used linear regression adjusted for age, sex, body mass index, and PH group to assess associations between metabolites and RV function. Pathway enrichment analyses were used to identify pathways significantly associated with RV function. Interaction terms were assessed to determine whether metabolite associations were modified by pulmonary vascular resistance, group 1 PH status, or sex. Least absolute shrinkage and selection operator regression was used to develop metabolite-based scores for RV function, and prognostic performance was assessed. RESULTS: There were 979 participants with plasma metabolomics and RV function data. Linear regression identified 170 metabolites that were significantly associated with all 3 RV metrics. Androgenic steroid, gamma-glutamyl amino acid, polyamine, vitamin A, fatty acid, and sterol pathways are most strongly associated with RV systolic function. Two metabolites interacted with group 1 PH status, and 6 interacted with pulmonary vascular resistance. Four androgenic steroids are associated more strongly with RV systolic function in women compared with men. Metabolite-based scores were prognostically equivalent to RV systolic function metrics and less accurate than REVEAL Lite 2 scores. CONCLUSIONS: We provide a blueprint of metabolites and metabolic pathways associated with RV systolic function across the spectrum of PH. Novel links to vitamin A and glutathione metabolites were observed. We detected few metabolites that associated with RV systolic function differentially by group 1 PH status or degree of pulmonary vascular resistance elevation. Androgenic steroids may associate more strongly with RV systolic function in women compared with men.
Intraoperative 3D Transesophageal Echocardiography for Early Detection of Pulmonary Vascular Complications in Lung Transplantation: A Case-Based Teaching Series
Seminars in Cardiothoracic and Vascular Anesthesia | April 13, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available
Lung transplantation presents numerous intraoperative challenges, particularly related to pulmonary artery and vein anastomotic integrity and hemodynamic stability. We present 3 cases where intraoperative transesophageal echocardiography (TEE) provided real-time diagnostic insights that directly altered surgical decision-making. Case 1 highlights pulmonary vein flow acceleration initially concerning for ostial stenosis, ultimately diagnosed as external compression from a retractor. Case 2 demonstrates true right pulmonary vein stenosis requiring immediate revision. Case 3 illustrates severe right pulmonary artery narrowing, detected by TEE and corrected intraoperatively to prevent early graft dysfunction. These cases underscore the critical role of intraoperative TEE in detecting subtle anastomotic abnormalities, distinguishing functional from structural stenosis, and guiding timely surgical correction. Incorporating comprehensive 2D and 3D TEE evaluation into routine lung transplant protocols enhances diagnostic accuracy, reduces postoperative complications, and contributes to improved long-term allograft function. Intraoperative 3D TEE should be considered an essential imaging modality in cardiothoracic transplantation and an invaluable educational tool for perioperative teams.
The Lung: Physiologic Basis of Pulmonary Function Tests
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