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JCO Precision Oncology

● American Society of Clinical Oncology (ASCO)

Preprints posted in the last 90 days, ranked by how well they match JCO Precision Oncology's content profile, based on 14 papers previously published here. The average preprint has a 0.02% match score for this journal, so anything above that is already an above-average fit.

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Axitinib in Progressive Metastatic Pheochromocytoma and Paraganglioma: Results of a Phase II Study

Del Rivero, J.; Apolo, A.; Edgerly, M.; Figg, W. D.; Lee, J.; Ausiello, J.; Pacak, K.; Bates, S. E.; Fojo, T.

2026-09-30 oncology 10.64898/2026.09.28.26364204 medRxiv
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Purpose: Metastatic pheochromocytoma and paraganglioma (PPGL) are rare neuroendocrine malignancies with limited systemic treatment options. Although inhibition of vascular endothelial growth factor (VEGF) signaling has demonstrated clinical benefit in metastatic PPGL, prospective data evaluating selective VEGF receptor inhibition remain limited. Axitinib is a potent and selective inhibitor of VEGFR-1, -2, and -3 with established activity in several solid tumors. We evaluated the efficacy and safety of axitinib in patients with progressive metastatic PPGL. Methods: Patients with progressive metastatic or unresectable PPGL were enrolled in a prospective, open-label, single-arm, phase II study (NCT03839498). Eligible patients had measurable disease according to RECIST version 1.1 and no prior treatment with a tyrosine kinase inhibitor. Axitinib was administered orally at an initial dose of 5 mg twice daily with protocol-defined dose modifications based on tolerability. The primary endpoints were objective response rate (ORR) and progression-free survival (PFS). Safety was assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE). Results: Nineteen patients were enrolled, and 17 received study treatment. A confirmed partial response was achieved in 35.3% of treated patients. Median progression-free survival was 7.9 months (95% CI, 6.1-16.8 months), median duration of response was 7.4 months, median duration of treatment was 9.5 months, and median overall survival was 29 months. Hypertension, the most common treatment-related adverse event, occurring in 79% of patients, was effectively managed with antihypertensive therapy and dose modification. Other common treatment-related adverse events included fatigue, diarrhea, oral mucositis, and palmar-plantar erythrodysesthesia. No patient permanently discontinued treatment because of treatment-related toxicity. Conclusions: In patients with progressive metastatic PPGL, single-agent axitinib demonstrated clinically meaningful antitumor activity with a manageable safety profile. The observed efficacy compares favorably with sunitinib in this rare disease. The ability to maintain treatment despite predictable VEGF-associated toxicities suggests that axitinib represents a viable therapeutic option for patients with metastatic PPGL.

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Effectiveness of a Molecular Tumor Board in Making Personalized Treatment Recommendations for Patients with Advanced Cancer

Rose, A.; Basik, M.; ferrario, c.; fallah, p.; friedmann, j.; batist, g.; spatz, a.; kavan, p.; lau, s.; Aguilar-Mahecha, A.; Mamo, A.; papadakis, a.; Panet, F.; labidi, s.; lafleur, J.; Harrigan, D.; VINCENT RAJADURAI, C.; elkholi, i.

2026-10-02 oncology 10.64898/2026.10.01.26364445 medRxiv
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ABSTRACT BACKGROUND: Next-generation sequencing (NGS) and the development of targeted therapies have revolutionized cancer treatment. Molecular Tumour Boards (MTB) serve as collaborative platforms to integrate individual clinical and molecular information to make recommendations for personalized treatment. METHOD: This is a single-center, retrospective cohort study of patients presented at the Jewish General Hospital (JGH) MTB between July 2018 and Dec 2022. Clinical, molecular/pathologic data, MTB recommendations, and treatment details were collected. Treatment response was determined by radiological evaluation and physician clinical assessment. Fishers exact test and Log-rank tests were used to assess differences between groups. RESULTS: A total of 328 patients were presented to the MTB, including 23 with repeat presentations, resulting in 355 case reviews. Tumour-agnostic biomarkers were detected in 18.9% of cases, most commonly high tumour mutational burden (TMB, 9.5%) and HER2 amplification (4.3%). The most frequent actionable mutations were PIK3CA (19.8%) and PTEN (13.1%), often leading to recommendations for mTOR inhibitor therapy (26.0%). Overall, therapeutic recommendations were issued in 84.5% (300/355) of cases, and implemented in 43.3% (130/300). Patients who received MTB-recommended therapies achieved significantly higher objective response rates (ORR) (14.2% vs. 4.2%; P = 0.047), longer real-world progression-free survival (rwPFS) (5.6 vs. 3.5 months; HR 0.57; 95% CI 0.390 - 0.828; P = 0.003), and improved median overall survival (OS) (12.8 vs. 5.2 months; HR 0.60, 95% CI 0.452 - 0.793; P < 0.001) compared with those treated without MTB guidance. CONCLUSION: MTB is effective in identifying biomarker-matched therapeutic recommendations for advanced malignancies where limited standard-of-care treatment option is available.

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Prior immune checkpoint inhibitor exposure, treatment interval, and severe hepatotoxicity with sotorasib in KRAS G12C-mutant non-small-cell lung cancer: a systematic review and meta-analysis

Cook, S.; Kim, H. S.

2026-10-07 oncology 10.64898/2026.10.05.26364739 medRxiv
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Background: Severe hepatotoxicity has been reported when sotorasib follows immune checkpoint inhibitor (ICI) therapy, and fixed washout intervals have been proposed. We assessed prior ICI exposure and the ICI-to-sotorasib interval as separate risk factors. Materials and methods: We searched PubMed, Europe PMC, Embase, Web of Science, Scopus, CENTRAL, and meeting proceedings for comparative studies of grade 3 or higher hepatotoxicity after KRAS G12C inhibitors. Matched risk ratios (RRs) and unadjusted cohort data were synthesized separately, the latter with an exact conditional odds ratio (OR). Certainty was rated with GRADE. Results: Of 530 unique records screened, seven sources were included, all involving sotorasib. In the only matched analysis (meeting abstract, 386 patients per arm), prior ICI exposure was associated with higher risk (13.2% vs 4.4%, RR 3.00, 95% CI 1.76-5.10), whereas matched comparisons at 6 weeks (RR 1.11, 0.61-2.03) and 12 weeks (RR 1.08, 0.52-2.27) detected no difference but could not exclude important effects. All five unadjusted cohorts showed higher risk with shorter intervals, including 21/74 versus 8/75 patients in the earlier versus later interval quartiles of the CodeBreaK 200 trial, although effect sizes were heterogeneous (exact homogeneity P=0.006). Certainty was very low throughout. Conclusions: Prior ICI exposure was associated with higher risk of severe sotorasib-associated hepatotoxicity, with very low certainty. A shorter interval was associated with higher risk in unadjusted data only, and current evidence does not establish a mandatory washout period. Liver-test monitoring per the prescribing information applies to all patients, whereas additional surveillance after ICI exposure remains an untested precaution.

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No Overall Survival Benefit with Adding Chemotherapy to Immunotherapy in PD-L1 TPS >= 50% NSCLC: An Agent-Stratified Reassessment

Han, F.; Wang, J.; Shi, S.; Jin, M.; Ren, C.

2026-09-03 oncology 10.64898/2026.09.01.26361919 medRxiv
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IMPORTANCE: A recent meta-analysis showed that chemoimmunotherapy was associated with improved overall survival (OS) compared with immune checkpoint inhibitor (ICI) monotherapy for programmed death-ligand 1 (PD-L1) tumor proportion score (TPS) [&ge;] 50% advanced non-small-cell lung cancer (NSCLC). However, whether this benefit reflects chemotherapy effect or ICI heterogeneity remains unclear. OBJECTIVE: To reassess the survival benefit of adding chemotherapy to ICI monotherapy using agent-stratified comparisons anchored to chemotherapy. DATA SOURCES: The 24 phase 3 randomized clinical trials included in the original meta-analysis (search date, August 3, 2025). DATA EXTRACTION AND SYNTHESIS: Hazard ratios (HRs) for OS and progression-free survival (PFS) were extracted from each trial in the original meta-analysis. Two analytic frameworks were used: within-agent comparisons (same ICI in both chemoimmunotherapy and monotherapy) and across-agent comparisons (ICI in one treatment strategy only). For within-agent comparisons, a two-stage random-effects meta-analysis was conducted. In stage 1, ICI-specific HRs for chemoimmunotherapy and ICI monotherapy versus chemotherapy were pooled and their ratio was calculated (RHR = HRchemoimmuno/HRmono; RHR < 1 favors chemoimmunotherapy). The RHRs were pooled in stage 2. For across-agent comparisons, RHR was derived from pooled HRs by treatment strategy. MAIN OUTCOMES AND MEASURES: Endpoints were OS and PFS. RESULTS: In within-agent comparisons (4 ICIs; 13 trials; N = 3252), pooled RHR was 0.94 (95% CI, 0.78-1.13; P = .48; I2 = 0.0%) for OS and 0.85 (95% CI, 0.68-1.06; P = .14; I2 = 0.0%) for PFS. In across-agent comparisons (7 ICIs; 11 trials; N = 2231), RHR favored chemoimmunotherapy for OS (0.68; 95% CI, 0.50-0.92; P = .01) and PFS (0.46; 95% CI, 0.37-0.58; P < .001). In a sensitivity analysis restricted to trials of NCCN-recommended regimens, pooled RHR was 1.02 (95% CI, 0.81-1.28; P = .87) for OS. CONCLUSIONS AND RELEVANCE: In the within-agent comparisons, adding chemotherapy to ICI monotherapy did not improve OS or PFS in patients with PD-L1 TPS [&ge;] 50% advanced NSCLC. The benefit in the original meta-analysis appears driven by across-ICI heterogeneity. These findings are consistent with ICI monotherapy as a standard first-line option and underscore the need for agent-level stratification in across-trial comparisons.

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Mifamurtide for Osteosarcoma in the United States: A Single-Center Real-World Experience

Slotkin, E. K.; Mauguen, A.; Roach, J.; Dela Cruz, F. S.; Glade Bender, J. L.; Ortiz, M. V.; Pavisic, J.; Babatunde, O. O.; Banks, L. B.; Chi, P.; D'Angelo, S. P.; Dickson, M. A.; Gounder, M. M.; Kelly, C. M.; Keohan, M. L.; Maki, R. G.; Movva, S.; Tap, W. D.; Berman, L.; Diamantis, K.; Hennessy, J.; Henelley, C.; Kelly, P.; Sauerhaft, T.; Voccola, J.; Reed, D. R.; Wexler, L. H.; Meyers, P. A.

2026-10-06 oncology 10.64898/2026.10.04.26364693 medRxiv
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Purpose: Mifamurtide (liposomal muramyl tripeptide phosphatidylethanolamine [L-MTP-PE] is approved in many countries for osteosarcoma but remains unavailable for routine use in the United States (US). We describe the feasibility and outcomes of patients with osteosarcoma treated with mifamurtide at Memorial Sloan Kettering Cancer Center (MSK) through expanded access (EAP) and compassionate use (SPU) pathways. Methods: Medical records were retrospectively reviewed for patients with completely resected, high-grade osteosarcoma treated with mifamurtide at MSK from 2016-2026 through EAP or SPU protocols. Mifamurtide 2 mg per meter squared was administered intravenously twice weekly for 12 weeks, followed by weekly administration for 24 weeks. Outcomes were evaluated by treatment setting and, for upfront therapy, metastatic status and histologic necrosis. Results: Fifty-seven patients received mifamurtide (median age, 14 years; range, 2-60); 72% had localized and 28% metastatic disease at diagnosis. No serious adverse events were considered possibly or probably related to mifamurtide, and no new grade 3-4 safety signals emerged. Five patients with localized disease and [&ge;]90% necrosis at resection had no events, with 100% progression-free survival (PFS) and overall survival (OS) at median follow-up of 29 months. Among 22 patients with localized disease and <90% necrosis treated upfront, PFS was 82%, 66%, and 59% at 12, 24, and 48 months, respectively; OS was 95% at 12, 24, and 60 months. Among 8 patients with metastatic disease treated upfront, PFS was 73%, 58%, and 39% at 12, 24, and 36 months, respectively; OS was 100%, 86%, and 86%. Among 22 patients treated after relapse, PFS was 34%, 23%, and 17% at 12, 24, and 36 months, respectively; OS was 91%, 70%, and 35% at 12, 24, and 60 months. Conclusions: In this real-world US cohort, mifamurtide was feasible and safe to administer. Despite limitations of the EAP/SPU setting, single-institution administration, and patient heterogeneity, overall survival outcomes were encouraging.

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Predictive markers of response and toxicity to tarlatamab in patients with extensive stage small cell lung cancer: a multi-institutional real-world analysis

Fenton, G.; Guo, W.; Hess, D. L.; Zhang, A. L.; Tatsuoka, C.; Green, A. L.; Sittig, M.; Mehra, R.; Simms, A.; Dowlati, A.; Owonikoko, T. K.; Hsu, M.; Alder, L.; Rosner, S.

2026-10-05 oncology 10.64898/2026.10.02.26364624 medRxiv
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Purpose Tarlatamab, a bispecific T-cell engager, has generated favorable response and survival outcomes in relapsed small cell lung cancer (SCLC). Factors influencing tarlatamab-associated treatment outcomes and toxicity have yet to be established. We performed a multivariate analysis to identify biomarkers associated with cytokine release syndrome (CRS) and immune effector cell associated neurotoxicity syndrome (ICANS) and integrated these variables into a novel risk stratification tool to identify patients at high risk of clinically significant toxicity. Patients and Methods Logistic and ordinal regression analyses evaluated the predictive value of variables contributing to the presence and severity, respectively, of CRS and ICANS in 115 patients with ES-SCLC receiving tarlatamab. Selected variables were then tuned using 5-fold cross-validation and incorporated into novel elastic net-based prediction models. Results Rates of observed CRS, ICANS, and dysgeusia were 46%, 28%, and 47%, respectively. ORR (overall response rate) and DCR (disease control rate) were 44% and 58.2%, while 6-month PFS (progression free survival) and OS (overall survival) rates were 30.4% and 54.9%, respectively. Excluding patients on tarlatamab <30 days, presence of dysgeusia was associated with a lower rate of disease progression (HR 0.44, p=0.00691) and death (HR 0.34, p=0.0145). The presence of, increased size and number of extracranial metastases as well as elevated baseline LDH were significantly associated with increased likelihood of CRS. Increased ECOG performance status, increased volume of brain metastases, development of CRS, and elevated baseline LDH were all associated with increased risk of developing ICANS. Our cross-validated risk model successfully predicted CRS grade [&ge;]2 and ICANS events with 90.9% and 75% sensitivity, respectively. Conclusions This exploratory analysis identified several predictive biomarkers of toxicity that successfully stratified low and high-risk populations as part of an internally validated novel risk scoring tool.

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Multimodal Immune Profile Score (IPS) as a Pan-Cancer Biomarker for Stratifying Outcomes of Immune Checkpoint Inhibitor Benefit in Microsatellite Stable Colorectal Cancer and Rare Solid Tumors

Ting-Lin, M. A.; Antonarakis, E. S.; Wang, X.; Erbe, R.; Zander, A. D.; Liu, Y.; Jin, A.; Vidal, G. A.; Haake, S. M.; Stein, M. M.; DeSantis, D. F.; Beauchamp, K. A.; Campbell, M. E.; Cohen, E. E. W.; Hyun, S. W.; Kelly, R. J.; Kalyan, A.; Bashir, B.; Rimel, B. J.; Herzog, T. J.; Chiou, V. L.; Sangli, C.; Nimeiri, H.; Carlson, J.; Simeone, D. M.; Strickler, J. H.

2026-10-09 oncology 10.64898/2026.10.07.26364989 medRxiv
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Background Immune checkpoint inhibitor (ICI) therapies have revolutionized oncology, but identifying patients who benefit remains a challenge, particularly in populations where ICIs are not the standard of care, including microsatellite stable colorectal cancer (MSS CRC) and rare solid cancers. We evaluated real-world performance of the Immune Profile Score (IPS), a validated DNA- and RNA-based molecular signature, in these cohorts. Methods In an exploratory analysis, we analyzed two real-world cohorts: 1) MSS CRC; and 2) MSS, tumor mutational burden-low rare solid cancers treated with off-label ICI. IPS-High and IPS-Low were calculated using a previously validated threshold. Cox proportional hazards models were fit to demonstrate prognostic utility for real-world overall survival (rwOS). In MSS CRC, time-to-next-treatment (TTNT) on prior non-ICI therapy was compared to rwOS on subsequent ICI therapy. Results In MSS CRC (n=46), IPS-High patients (13%) demonstrated clinically meaningful improvement in rwOS versus IPS-Low (Median OS: not reached vs 7.3 months; HR = 0.22, 90% CI 0.04-1.16). While IPS was not associated with TTNT on the preceding non-ICI line (HR = 1.07, 90% CI 0.60-1.91), it was associated with OS in patients receiving later line ICI (HR 0.21, 90% CI 0.04-1.22). In the rare cancers cohort (n=90; 26 unique malignancies), IPS-High (17.8%) was associated with longer OS to ICI therapy (HR = 0.26, 90% CI 0.11-0.61), even when restricted to histologies represented in both IPS groups (HR = 0.18, 90%, CI 0.05-0.62). Conclusions Preliminary evidence suggests that IPS may serve as a generalizable, pan-cancer biomarker capable of stratifying outcomes for ICI treatment in populations traditionally excluded from immunotherapy benefit.

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Cell-Free DNA Concentration as a Mutation-Agnostic Readout of Systemic Tumor Burden and Prognosis: A Prospective Analysis of 1,000 Patients

Leonard-Murali, S.; Chandramouli, M.; Sherry, C.; Patel, S.; Vue, N.; Petrosko, P.; Gallo, P. H.; Schumacher, P. E.; Shannon, A. H.; Allen, C. J.; Nakayama, J. M.; Rachman, T. W.; Carja, O.; Schwartz, R. S.; Zaidi, A. H.; LaFramboise, W. A.; Bartlett, D. L.; Wagner, P. L.

2026-07-28 oncology 10.64898/2026.07.27.26359064 medRxiv
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Background: Objective assessment of tumor burden in patients with solid tumors remains inexact. Furthermore, while mutation-based liquid biopsies are specific, they are limited by tumor heterogeneity and the requirement for detectable clonal mutations. Cell-free DNA (cfDNA) concentration, a cost-effective substrate for mutation-focused liquid biopsy, has shown promise as a "molecular tumor burden" biomarker. Methods: We analyzed cfDNA concentration from 1000 unique cancer patients using standardized protocols. Demographics, AJCC stage, clinical anatomic tumor burden and oncologic outcome variables were collected. Associations were assessed with non-parametric tests. Multivariable linear regression and Cox proportional hazards models were used to identify independent predictors and survival associations. Results: CfDNA concentration varied broadly (median 6.25 ng/mL; range 0.5-1132.9). Anatomic tumor burden, including tumor number (rho=0.25, p<0.0001) and largest tumor diameter (rho=0.25, p<0.0001), correlated significantly with cfDNA, especially in stage IV disease. Primary tumor site influenced cfDNA levels, with liver/bile duct cancers having higher cfDNA than other sites (median 13.5 vs 6.1 ng/mL, p<0.0001). Multivariable analysis confirmed overall tumor burden and hepatic tumor location (primary or metastatic) as principal drivers of cfDNA. Critically, cfDNA concentration was an independent predictor of shorter PFS (p=0.001) and DSS (p<0.0001), demonstrating increased value in advanced disease settings, irrespective of treatment intent. Conclusions: CfDNA concentration is a robust, biologically integrated biomarker that provides an objective measure of total systemic tumor burden and prognosis in a large, pan-cancer cohort. By capturing disease activity irrespective of mutational status, it offers a valuable adjunct to targeted profiling, particularly in heterogeneous or advanced malignancies. Although these findings require prospective clinical validation, cfDNA concentration may eventually augment patient selection for aggressive versus palliative interventions, especially in advanced disease.

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Lanreotide for Advanced Pheochromocytoma and Paraganglioma: Results of a Multicenter Phase II Trial

Del Rivero, J.; Laderian, B.; Zhou, M.; Luk, L.; Bates, S. E.; Fojo, T.

2026-10-02 oncology 10.64898/2026.10.01.26364504 medRxiv
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Background: Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine neoplasms originating from chromaffin cells that express somatostatin receptors (SSTRs) and may therefore be susceptible to somatostatin analogue therapy. Despite this biological rationale, prospective evidence supporting the antiproliferative activity of somatostatin analogues in PPGL is limited. We conducted a multicenter phase 2 clinical trial to assess the efficacy and safety of lanreotide in patients with advanced or metastatic PPGL. [LAMPARA, NCT03946527] Methods: Patients with advanced or metastatic PPGL and evidence of recent disease progression received lanreotide depot/autogel 120 mg subcutaneously every 4 weeks. Treatment was planned for 52 weeks with an option to continue for an additional 52 weeks. Endpoints included overall survival (OS), progression-free survival (PFS), and response according to RECIST. Serum chromogranin A (CgA) was evaluated as an exploratory biomarker. A tumor growth rate analysis was planned to allow comparison with data from the CLARINET trial in gastroenteropancreatic NETs. Results: Eighteen patients (median age 42 years; range 28-77) across three centers participated; 78% carried SDHx mutations. Lanreotide was well tolerated with predominantly grade 1-2 adverse events and no treatment discontinuations due to toxicity. The most common treatment-emergent adverse events were diarrhea (67%), injection-site reaction (44%), constipation (39%), fatigue (39%), and abdominal pain (39%). Serious adverse events were reported in four patients and were assessed as not related or unlikely related to lanreotide. All 18 patients had at least one recorded post-baseline tumor assessment. Two partial responses were recorded during extended follow-up. At approximately 1 year, disease stabilization was observed in 11 of 13 patients (85%) with an available assessment, while two patients (15%) had progressive disease. Biomarker analysis showed substantial variability in serum CgA values. Tumor growth rate analysis revealed a median growth rate of 0.00124/day (tumor doubling time 559 days), comparable in order of magnitude to the rate of 0.00046/day observed in 83 lanreotide-treated patients in CLARINET, and consistent with a median PFS [&ge;]2 years. Conclusions: Lanreotide exhibits promising antiproliferative activity in PPGL, with a favorable safety profile and extended periods of disease stabilization. These findings support the consideration of SSAs as an option in managing SSTR-positive PPGLs, delaying more aggressive treatments until disease progression mandates escalation.

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Genome Profiling of Actionable Cancer Targets (NYU LG-PACT) for Clinical Patient Molecular Diagnostics and Treatment

Yang, Y.; Vasudevaraja, V.; Serrano, J.; Mohamed, H.; Kelly, S.; Jour, G.; Gindin, T.; Park, K.; Jones, D.; Feng, X.; Pinnell, J.; Mclennan, S.; Tin, M. Y.; Tsirigos, A.; Snuderl, M.; Wrzeszczynski, K. O.

2026-09-01 oncology 10.64898/2026.08.27.26361341 medRxiv
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Next-generation sequencing (NGS) for the detection of somatic variants has become the method of choice in a variety of molecular oncology fields and in the clinic. Its use ranges from sequencing entire tumor genomes and transcriptomes to targeted clinical diagnostic gene panels. The NYU Langone Genome PACT (Profiling of Actionable Cancer Targets, LG-PACT) assay is a qualitative in vitro diagnostic test that uses targeted next generation sequencing (NGS) of formalin-fixed paraffin-embedded (FFPE) tumor tissue matched with normal specimens from patients to detect gene alterations in a targeted panel covering 606 genes and the TERT promoter. Indications for testing are cancer (solid tumors and hematological malignancies) where a mutational profile from multiple genes would be informative for disease stratification, prognosis, or treatment options including targeted therapies and eligibility for clinical trials. The test is intended to provide information on somatic mutations including point mutations, small insertions/deletions (indels), and copy number aberrations for diagnostic and treatment decisions. LG-PACT is a United States Food and Drug Administration (FDA) cleared diagnostic test (510K: K202304). The clinical interpretation of sequencing data of molecular tumor markers from NGS encompasses automated variant calling tools with human interpretation. This final mostly manual review of data step is intensive, involving highly trained scientists, encompassing literature review, interpretation and clinical tier classification by pathologists, who then provide a complete molecular diagnostic report to the treating oncologists. We provide analysis of 1339 clinical genomic profiles from 31 different cancers and their subtypes, comprising of central nervous system (CNS) 792 (59%) cases (incl. meningioma, glioma and glioblastoma), with 267 (20%) cases predominantly of lung, pancreatic and colorectal and 280 of others (21%). Here, we present the technical challenges of validating an NGS oncological diagnostic targeted assay for clinical grade accuracy and sensitivity for patient care. We show how copy number alterations provide a more comprehensive description of the tumors genomic profile. We then outline the utility of targeted panel sequencing based on certified pathologist selection of reportable variants for our current patient cohort. Where analysis of variant detection has led to 49.4% (661/1339) of our clinical tumor samples containing mutations in known therapy targeted genes, 35.6% (477/1339) with mutation detected in other genes, and 15% (201/1339) cases being negative.

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Peripheral Biomarkers and Determinants of Survival for Patients with Melanoma Brain Metastasis Treated with Immune Checkpoint Blockade

Hassan, J.; Little, M.; Farkas, A.; Mackay, S.; Coupe, N.; Middleton, M.; Payne, M. J.; Fairfax, B.

2026-10-21 oncology 10.64898/2026.10.19.26365947 medRxiv
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Background Immune checkpoint blockade (ICB) has become the standard of treatment for metastatic melanoma (MM). However, patients with melanoma brain metastases (MBM) are often excluded from clinical trials. Here we analyse patients within the real-world OxCITE cohort receiving ICB treatment for metastatic melanoma, with a focus on MBM, aiming to discern outcomes, prognostic factors and peripheral biomarkers. Methods Patients eligible for ICB treatment were recruited prospectively. Demographic, clinical and radiological data were collected from electronic patient records. Plasma samples were collected prior to the first cycle of treatment for plasma proteomic analysis. Results 307 patients were included, 81 of whom had MBM on commencing ICB. No difference in overall survival between patients with and without brain metastases was noted on multivariable analysis (HR=1.1, 95% CI 0.73-1.6, p=0.68), whereas hepatic metastases were associated with increased risk of death (HR 1.7, 95% CI 1.2-2.4, p=0.0019). Within the MBM group, steroid treatment (HR=2.5, 95% CI 1.3-5.0, p=0.006) was associated with poor OS, whilst treatment with single agent ICB (HR=1.9, 95% CI 0.86-3.9, p=0.11), symptomatic first presentation of MBM (HR=1.5, 95% CI 0.76-2.8, p=0.25) and anti-seizure drug treatment (HR=1.74, 95% CI 0.89-3.4, p=0.10) were not. Amongst all patients carriage of a BRAF mutation was associated with increased risk of MBM (OR 2.49, 95% CI 1.4-4.4, p=0.0007), and increased propensity to new brain metastases on ICB treatment (OR 2.5, 95% CI 1.1-5.9, p=0.036). Analysis of blood and plasma samples demonstrated that patients with MBM have altered haematological profiles, with raised NLR and increased plasma glial fibrillary acidic protein levels, reinforcing the distinct systemic features of MBM. Conclusions In this real-world cohort of patients receiving ICB for metastatic melanoma, the presence of MBM did not associate with worse OS. Conversely, baseline corticosteroid use was adversely prognostic. Intriguingly, plasma GFAP was significantly elevated in patients with MBM and correlated with the burden of intracranial disease, highlighting a potential role for GFAP as a candidate biomarker for MBM in high-risk surveillance. Our observations indicate the adversely prognostic weight historically attached to M1d disease is no longer applicable in the ICB era.

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Does the Disease-free Survival Benefit of Adding Belzutifan to Adjuvant Pembrolizumab Persist Beyond the Planned Treatment Period? A Reconstructed Individual Patient Data Analysis of Phase 3 Renal Cell Carcinoma Trials

Chang, H.-H.; Chang, C.-K.; Tang, T.-Y.; Jhan, J.-H.; Dong, S.-W.; Juan, Y.-S.; Geng, J.-H.; Ou, H.-C.; Lee, H.-Y.; Li, C.-Y.; Yeh, H.-C.; Leong, M.-K.; Liu, C.-H.; Lee, Y.-C.; Huang, S.-P.

2026-10-16 oncology 10.64898/2026.10.14.26365591 medRxiv
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Background and Objective: Adding belzutifan to adjuvant pembrolizumab improved disease-free survival (DFS) in LITESPARK-022, but its durability beyond the 1-year treatment is unknown. Methods: Following a registered plan, we reconstructed individual patient data from published Kaplan-Meier curves of ten phase 3 adjuvant renal cell carcinoma trials. Within each trial, we estimated restricted mean survival time differences ({Delta}RMST), hazard ratios (HRs) before and after planned treatment ended, and DFS differences. Key Findings and Limitations: In LITESPARK-022 (central review), the 24-month {Delta}RMST was 1.34 months (95% confidence interval 0.73-1.95), and the belzutifan arm remained ahead after month 12 ({Delta}RMST increment 0.74 months/yr, 0.32-1.19). The HR was 0.55 (0.43-0.71) before month 12 and 1.16 (0.87-1.54) afterwards (post/pre ratio 2.10); investigator assessment showed similar attenuation. Similar ratios occurred in KEYNOTE-564 at its first interim analysis (2.02), whose benefit persisted, and in SORCE and PROTECT (2.09, 2.59), whose benefit faded. From months 12 to 30 (post hoc), the DFS difference changed by -3.7 percentage points (-8.1 to 0.8) with central review and 0.6 (-4.0 to 5.0) with investigator assessment. Data were reconstructed, and follow-up was short. Conclusions and Clinical Implications: Relative hazard reductions with belzutifan were greater before month 12; durability of the absolute DFS advantage is uncertain and assessment-dependent, so single-HR projections should be avoided.

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Phase I Trial Representation and Geographical Distribution in Mesothelioma and Thymic Epithelial Tumors

Mishra, S.; Qorbani, M.; Canaslan, K.; Maniar, R.; Emami, A. H.; Nia, F. M.; Janbabi, G.; Rezaei, Z.; Ardeshir-Larijani, F.

2026-08-11 oncology 10.64898/2026.08.09.26360015 medRxiv
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Background and Purpose: Rare thoracic tumors face persistent exclusion from clinical trials. To address this, we characterized the representation, geographical distribution, mechanisms of action, and clinical outcomes of Phase I trials in thymic epithelial tumors (TETs) and mesothelioma. Materials and Methods: Phase I solid-tumor trials from Jan 1995 to Jan 2026 were identified on ClinicalTrials.gov and processed using Python to extract trial status. A Python pipeline identified TET and mesothelioma trials and divided them into resulted and non-resulted trials. Resulted trials underwent manual review, and publication status was verified through PubMed, Google Scholar, and LARVOL CLIN. Results: Of 6,610 Phase I trials screened, 3.1% (n=203) included rare thoracic tumors. Among these, 11.3% (n=23) reported results, 34.8% (8/23) advanced beyond Phase I, and 21.7% (n=5) were published in high-impact journals (IF > 10). Targeted therapies dominated classifications (65.2%), followed by immunotherapies (34.8%) and antibody-drug conjugates (ADCs; 8.7%). Reported efficacy outcomes showed wide ranges: objective response rate (ORR, 0-44%), progression-free survival (PFS, 1.3-8.3 months), and overall survival (OS, 3.0-19.3 months). Fatigue was the most frequent toxicity, observed in 58% of targeted therapy trials and 100% of immunotherapy and ADC cohorts. No novel agents achieved subsequent disease-specific FDA approval. Geographically, among 96 trial locations, 49.0% were concentrated in Europe and 21.9% in the United States. Conclusions: Current Phase I trials exhibit a striking scarcity of research for mesothelioma and TETs, concentrated predominantly in high-income regions. Bridging this gap requires prioritizing rare thoracic tumors and building clinical infrastructure in underrepresented countries to enhance trial access and diversity. Keywords: Thymic epithelial tumors, Mesothelioma, Phase I clinical trials, ClinicalTrials.gov, Rare thoracic malignancies.

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Oncogene Driver Status Modulates TP53 Prognostic Impact in Advanced NSCLC

Pan, M.; Jiang, C.; Song, J.; Kudrimoti, S.; Aredo, J. V.; Wakelee, H. A.; Neal, J. W.; Zhao, J.; Kamgarhaghighi, Y.; Achacoso, N. S.; Solorzano, A. V.; Tse, P.; Chung, E.; Sakoda, L.; Suga, M. J.; Thomas, S.; Habel, L.

2026-09-08 oncology 10.64898/2026.09.04.26362258 medRxiv
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Purpose: We compared the association of concurrent TP53 pathogenic variants (PV) with overall survival (OS) by driver status in non-small cell lung cancer (NSCLC). Patients and Methods: The discovery cohort included 3,295 patients with stage IV NSCLC treated at Kaiser Permanente Northern California. The validation cohort included 12,982 NSCLC from 37 public cBioPortal studies. Driver-positive disease was defined as presence of EGFR, ALK, or ROS1 alteration. We used Cox regression modeling to estimate hazard ratios (HRs) for mortality, adjusting for demographics and other factors. Results: Among the discovery cohort, TP53 PV was associated with worse OS among patients with an EGFR, ALK, or ROS1 alteration (HR = 1.80, [95% confidence interval (CI), 1.50-2.15]) but not among those without a driver mutation (HR = 1.08, [95% CI, 0.97-1.21]). Among the validation cohort, TP53 PV was associated with worse OS with HR of 2.27 [1.92-2.69], 2.42 [1.42-4.10], 1.30 [1.20-1.42], and 3.09 [95% CI, 1.47-6.47], for EGFR-activating, ALK-fusion, EGFR/ALK wild-type disease and RET-fusion respectively. The differential association was largest in EGFR exon 20 insertion tumors, in which TP53 PV carried HR = 4.68 [95% CI, 2.34-9.37], 3.9-fold that in driver-negative disease; the corresponding ratio for ERBB2 exon 20 insertions were 1.23 [95% CI, 0.75-2.02]. TP53 PV was not associated with OS in squamous carcinoma. Conclusions: Association of TP53 PV with OS in advanced NSCLC appears to depend on co-occurrence of other driver mutations. This driver-dependent effect modification informs interpretation of TP53 status and may be useful for risk stratification in clinical practice.

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Multimodal Machine Learning for Predicting Outcomes in the PASS-01 Trial of Systemic Therapy for Metastatic Pancreatic Cancer

Quan, W.; Henault, D.; Zhang, A.; Jang, G. H.; Hasnain, S. M.; Bevacqua, D.; Deng, Y.; Flores-Figueroa, E.; Ni, K.; Light, N.; Wilson, J. M.; Dodd, A.; Tsang, E. S.; King, D. A.; Habowski, A. N.; Yu, K.; Perez, K.; Aguirre, A. J.; O'Reilly, E. M.; Wolpin, B. M.; Pugh, T. J.; Tuveson, D. A.; Jaffee, E. M.; Gallinger, S.; O'Kane, G.; Notta, F.; Knox, J. J.; Grant, R. C.

2026-08-27 oncology 10.64898/2026.08.24.26360900 medRxiv
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Purpose Modified FOLFIRINOX (FFX) and gemcitabine plus nab-paclitaxel (GNP) are standard first-line treatments for metastatic pancreatic ductal adenocarcinoma (PDAC), but no validated biomarker guides treatment selection. We developed MULTIPL, a multimodal machine learning system, and established the PASS-01 Challenge to benchmark prognostic and predictive biomarkers. Patients and Methods MULTIPL was trained in the COMPASS study (N=268), integrating clinical, digitized histopathology, whole-genome, and RNA-seq data. MULTIPL, PurIST, hENT1 expression, and HRDetect were evaluated in the PASS-01 trial, a randomized phase II trial of FFX versus GNP (N=160), within the Challenge. The primary endpoint was differential treatment benefit measured by concordance-for-benefit for progression-free survival. Results MULTIPL had the highest concordance index for OS among individually evaluated biomarkers (0.595; 95% confidence interval [CI], 0.55-0.65) and separated high- versus low-risk patients (hazard ratio, 1.62; 95% CI, 1.13-2.33; P=0.009). Patients recommended for GNP by MULTIPL had significantly longer OS with GNP than with FFX (hazard ratio, 0.47; 95% CI, 0.28-0.82; P=0.007), whereas patients recommended for FFX had similar OS between treatments. Interpretability analysis of MULTIPL in COMPASS identified KDM6A alterations and SSTR1 expression as prognostic biomarkers, which were validated in PASS-01. However, none of the tested biomarkers significantly predicted differential treatment benefit in the PASS-01 Challenge. Conclusion MULTIPL demonstrated robust prognostic performance in external validation, identified a subgroup enriched for benefit from GNP, and enabled discovery and validation of prognostic biomarkers in metastatic PDAC. However, no biomarker met the primary endpoint for differential treatment benefit, underscoring the value of the PASS-01 Challenge.

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Genetic Determinants of Chemotherapy-Induced Oral Mucositis in Children with Solid Malignancies

Chawla, A.; Halman, A.; See, M.; Grobler, A. C.; Rossello, F.; Moore, C.; Carter, S. M.; Conyers, R.

2026-08-07 oncology 10.64898/2026.08.05.26359776 medRxiv
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Background: Oral mucositis is a clinically significant, potentially severe side effect of systemic chemotherapy in children with cancer. Understanding genetic predisposition to this side effect may assist in development of stratified prophylactic and treatment strategies. However, existing literature primarily focuses on children with haematological malignancies. Methods: We performed a candidate gene study of 101 children with solid tumours enrolled in the MARVEL-PIC study at the Royal Children's Hospital, Melbourne. Clinical data were extracted from the electronic medical record, with NCI-CTCAE v6.0 grade >2 oral mucositis defined as the primary outcome. Genetic variants previously associated with oral mucositis were analysed under an additive genetic model to identify significant associations. Exploratory gene-drug interactions were identified based on chemotherapy exposure. Results: 29 patients (28.7%) developed grade >2 oral mucositis. MTHFR A1298C (rs1801131) was associated with lower odds of grade >2 oral mucositis, lower peak mucositis grade, and lower odds of opioid use for oral mucositis. 25 exploratory gene-drug interaction signals were identified, including miR-1206 rs2114358 with methotrexate exposure and ABCB1 rs1045642 with anthracycline exposure. Conclusions: MTHFR A1298C (rs1801131) demonstrated a protective effect against chemotherapy-induced oral mucositis in our cohort of children with solid tumours. Larger, ancestry-informed studies are required to validate our findings.

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Non-inferior survival and enhanced longevity with initial low-dose versus full-dose enzalutamide: a single-centre real-world prostate cancer study

Gorobets, O.; Vinh-Hung, V.

2026-09-02 oncology 10.64898/2026.08.28.26361616 medRxiv
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Background: Prostate cancer enzalutamide treatment is approved at a standard dose of 160 mg daily. Concerns for real-world patients -- older and more fragile than those enrolled in clinical trials -- have prompted consideration of initiating treatment with lower doses, but the long-term efficacy of this approach remains unknown. We evaluate the long-term survival and longevity in patients treated with standard versus upfront low-dose enzalutamide. Methods: Retrospective analysis of 151 patients treated with enzalutamide (102 receiving 160 mg; 49 receiving [&le;]80 mg) between 2014--2021 at the Centre Hospitalier Universitaire de Martinique, with complete follow-up through end of life (98.7% completeness of follow-up). Primary outcomes were overall survival (OS), progression-free survival (PFS), and longevity (attained age). Results: Doses [&le;]80 mg were associated with longer median OS (36.3 vs. 20.7 months), improved restricted mean OS (difference of 0.7 years, p=0.05), and enhanced longevity (median 82.5 vs. 78.3 years, p=0.004). PSA response rate at 12 weeks was higher with lower-dose (71.4% vs. 48.8%, p=0.016). In multivariable models adjusted for prognostic factors, [&le;]40 mg compared with 160 mg was non-inferior regarding OS (HR=0.61, 95% CI 0.36--1.06), superior regarding PFS (HR=0.59, 95% CI 0.35--0.99), and superior regarding longevity (HR=0.48, 95% CI 0.28--0.84). Bone metastasis, poor performance status, PSA response, time to PSA nadir, and disease duration were independent predictors of outcomes. A post-hoc analysis revealed a strong association between dose and physician-prescribing profiles, ranging from "endorse-lowest-dose" to "never-deviate-from-full-dose". Conclusions: Lower doses of enzalutamide were non-inferior to full-dose. Dose-adapted strategies warrant further investigation.

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Venetoclax-based Therapy Improves Outcomes across the Evolving Biology of t(11;14) Multiple Myeloma

Sudalagunta, P. R.; Ionescu, F.; Canevarolo, R. R.; Silva, M. C. S.; DeAvila, D.; Meads, M. B.; Zhao, X.; Perez, A.; Drekolias, D.; Irimia, R.; Thapa, S.; Patel, P.; Baz, R.; Shain, K. H.; Silva, A. S.; Grajales-Cruz, A.

2026-09-07 oncology 10.64898/2026.09.02.26361956 medRxiv
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Background: Translocation t(11;14) defines a biologically distinct subset of multiple myeloma (MM) enriched for BCL2 dependency. Treatment with venetoclax, selective BCL2 inhibitor, has shown varied responses in clinical trials and retrospective cohorts. Efficacy of venetoclax-based combination therapies and optimal timing of treatment in t(11;14) MM patients remain incompletely characterized. Methods: We have compared the overall survival of t(11;14) MM patients who received Venetoclax (N = 97) at any moment in time, to those who never did (N =284), in the largest retrospective cohort (N = 381) reported to date. We used longitudinal fluorescence in situ hybridization (FISH) to assess cytogenetic evolution and genomic complexity. We performed transcriptomic profiling of CD138 enriched tumors using RNA sequencing in a subset of samples and gene expression signatures (UAMS/HALLMARKS) were used to define molecular subtypes. Ex vivo drug sensitivity assays integrated with paired RNA sequencing were used to identify subtype specific therapeutic vulnerabilities and rational venetoclax based combination strategies. Results: Venetoclax exposure was associated with an improvement of median overall survival by nearly four years compared to non VEN exposed patients (p = 0.0003). Longitudinal cytogenetic analysis demonstrated stability of the primary t(11;14) translocation over time, while secondary abnormalities tend to accumulate, including those harboring high-risk secondary cytogenetic abnormalities such as del13q, amp/gain1q21, del17p, and del1p, resulting in increasing genomic complexity with disease progression. Transcriptomic analyses identified selective enrichment of CD1/CD2 signature (associated with t(11;14) NDMM) by single sample gene set enrichment analysis as a marker of prolonged progression free survival. However, patients with more than five prior lines of therapy were enriched for transcriptionally complex biology characterized by CD1/CD2 with either proliferative/hypermetabolic or inflammatory transcriptional programming which were associated with inferior outcomes with VEN based treatment. Ex vivo drug sensitivity profiling revealed subtype specific vulnerabilities, identifying daratumumab, lenalidomide, ixazomib, and panobinostat as rational partners for venetoclax depending on transcriptional context. Conclusion: Venetoclax-based therapy significantly improved overall survival in t(11;14) MM. Clinical benefit, defined by improved progression free survival, was greatest when venetoclax was administered earlier, preceding the emergence of transcriptomic reprogramming that reduces BCL2 dependency. These findings support transcriptomic biomarker guided, subtype specific venetoclax based treatment strategies to optimize outcomes in patients with t(11;14) MM.

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Response-Adapted Bladder Preservation in Muscle-Invasive Bladder Cancer: Results of the Phase II RETAIN-2 Trial and Analysis of ctDNA Dynamics

Ghatalia, P.; Ross, E. A.; Zhang, L.; MacFarlane, A. W.; Zibelman, M. R.; Anari, F.; Abbosh, P. H.; Herberts, C.; Tester, W.; Mille, P. J.; Rose, T. L.; Cole, S.; Cheung, S. K.; Dutta, P.; Sharma, S.; ElNaggar, A. C.; Liu, M. C.; Mark, J. R.; Viterbo, R.; Horwitz, E.; Hallman, M. A.; Correa, A. F.; Smaldone, M. C.; Uzzo, R.; Chen, D. Y.; Campbell, K. S.; Kutikov, A.; Plimack, E. R.; Geynisman, D. M.

2026-08-27 oncology 10.64898/2026.08.24.26361206 medRxiv
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Purpose: Response-adapted bladder preservation has emerged as a potential alternative to immediate radical cystectomy for selected patients with muscle-invasive bladder cancer (MIBC), but biomarkers to guide treatment de-escalation are lacking. We report the clinical outcomes of the phase II RETAIN2 trial together with a retrospective circulating tumor DNA (ctDNA) analysis of the RETAIN1 and RETAIN2 studies. Patients and Methods: RETAIN2 prospectively evaluated neoadjuvant accelerated methotrexate, vinblastine, doxorubicin, and cisplatin (AMVAC) plus nivolumab followed by response-adapted management based on clinical restaging. A retrospective tumor-informed ctDNA analysis evaluated longitudinal ctDNA dynamics and associations with clinical outcomes. Results: Seventy one evaluable patients were enrolled in RETAIN2. The trial met its primary endpoint, with a 2 year metastasis free rate of 77.5% after a median follow-up of 34.7 months. Among 22 patients managed with active surveillance, 15 (68.2%) remained metastasis free with an intact, non irradiated bladder and 3 (13.6%) developed metastatic disease. In a sensitivity analysis using time to metastasis, the Kaplan Meier estimated 2 year metastasis free probability was 83.7% overall and 85.5% with active surveillance. Retrospective ctDNA analyses were performed in 111 patients from RETAIN1 and RETAIN2. Baseline and post-treatment ctDNA positivity were associated with metastatic progression and inferior overall survival. Among patients managed with active surveillance who were ctDNA-negative after treatment, the 2 year Kaplan Meier estimated metastasis free probability and overall survival were 91% and 97%, respectively. Plasma ctDNA predicted metastatic progression but not intravesical recurrence. Conclusion: Response adapted bladder preservation after neoadjuvant AMVAC plus nivolumab achieved encouraging long term outcomes in selected patients with MIBC. Retrospective ctDNA analyses suggest that plasma ctDNA reflects occult systemic disease rather than bladder confined recurrence and may refine patient selection for bladder preservation. These findings support prospective evaluation of ctDNA guided strategies while emphasizing the continued need for bladder directed surveillance and complementary urinary biomarkers.

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An AI Model Identifies Chemotherapy Benefit in Node-Negative HR+/HER2- Breast Cancer Patients from TAILORx, a Phase 3 Randomized Clinical Trial

Chan, N.; Tang, C.; Biswas, D.; Park, J.; Zeng, K.; Cappadona, J.; Liu, C.; McMclean, A.; Berrevoets, J.; Bao, L.; Machura, B.; Gray, R. J.; Wang, V.; Witowski, J.; Geras, K. J.; Sparano, J. A.; TAILORx Investigators,

2026-09-20 oncology 10.64898/2026.09.12.26362500 medRxiv
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BACKGROUND The prescribing of adjuvant chemotherapy for patients with breast cancer must balance the survival benefit against treatment-related toxicities. TAILORx, a phase 3 randomized clinical trial, demonstrated that endocrine therapy alone was, on average, noninferior to chemoendocrine therapy for patients classified as intermediate risk by a 21-gene Recurrence Score (RS) assay. Uncertainty remains about the optimal strategy to identify which intermediate-RS individuals derive benefit from chemotherapy. METHODS We analyzed 6735 patients from the TAILORx trial using Ataraxis Breast CTX with pathology images (H&E slides) and RS available. CTX is an AI model which integrates morphologic features extracted from H&E-stained slides with clinical variables to generate individualized predictions of prognosis (CTX-prognostic) and chemotherapy benefit (CTX-benefit). No data from TAILORx were used to train CTX and CTX was not retrained or recalibrated for this study. Analyses were prespecified in a protocol approved by ECOG-ACRIN. RESULTS Among patients treated with endocrine therapy alone, CTX-prognostic predicted disease-free interval (DFI), with a hazard ratio per 1 SD increase of 1.651 (95% CI, 1.511-1.803, p < 0.001) and C-index of 0.736 (95% CI, 0.697-0.770). Performance was similar in patients treated with chemoendocrine therapy (hazard ratio = 1.642 [95% CI, 1.495-1.804, p < 0.001], C-index = 0.720 [95% CI, 0.681-0.756]). After adjusting for the RS, CTX-prognostic remained significantly associated with DFI in both treatment groups. In the intermediate-RS subgroup, the treatment-by-biomarker interaction for CTX-benefit was significant (p = 0.001), with patients identified as high-benefit deriving a 5% increase in observed 5-year DFI rates from the addition of chemotherapy, compared with no detectable benefit in low-benefit patients. Stratifying the same subgroup by RS at a threshold selecting a similar proportion of patients yielded no significant interaction (p = 0.20). CONCLUSIONS In an analysis of TAILORx, CTX-prognostic stratified patients according to their risk of recurrence. Among intermediate-RS patients, CTX-benefit identified who derived clinically meaningful benefit from adjuvant chemotherapy, a population currently not identifiable by the RS alone.