JCO Precision Oncology

Background: Osimertinib is the standard first-line treatment for EGFR- mutant non-small cell lung cancer (NSCLC) harboring common activating mutations, including exon 19 deletions and L858R. It is also active against tumors with acquired T790M resistance. However, the EGFR L858R+T790M compound mutation, where both variants co-occur within the same tumor, may confer distinct drug-sensitivity profiles not predicted by either mutation alone. Limited data exist on comparative treatment outcomes in this rare genotype. Methods: Using the MSK-CHORD clinicogenomic dataset (n=24,950), we identified patients with concurrent EGFR L858R and T790M mutations receiving erlotinib (Erlo) or osimertinib (Osi) monotherapy. Real-world progression-free survival (rwPFS) per treatment line was calculated using a strict definition requiring confirmed radiological progression events (rwPFS-strict), excluding lines with null endpoint data. Kaplan-Meier analysis, log-rank testing, Cox proportional hazards regression, and cross-cohort heterogeneity testing (Cochran's Q statistic) were performed. Two control cohorts, L858R-only (n=372) and T790M-only (n=76), were analyzed in parallel to assess mutation-context specificity of treatment response. Results: Thirty-one patients with EGFR L858R+T790M were identified; 21 contributed evaluable monotherapy lines, yielding 23 Erlo and 15 Osi treatment lines (14 unique patients per treatment group, 7 contributing to both). Median rwPFS numerically favored Erlo over Osi (7.10 vs 5.32 months; HR 1.29, 95% CI 0.66-2.52; log-rank p=0.46). This directional trend was reversed in the L858R-only control cohort, where Osi demonstrated significant superiority (9.03 vs 5.75 months; HR 0.70, 95% CI 0.55-0.89; p=0.003). The T790M-only cohort showed no significant difference (HR 1.32, p=0.12). An exploratory post-hoc heterogeneity test confirmed a significant cross-cohort interaction (Q=9.94, df=2, p=0.007). Conclusions: The expected osimertinib advantage was absent in L858R+T790M compound-mutant NSCLC. The opposing hazard ratio directions across mutation contexts (HR 1.29 vs 0.70), with a significant exploratory cross-cohort interaction (p=0.007), suggest that the EGFR L858R+T790M compound mutation may represent a pharmacologically distinct entity with differential TKI sensitivity. These hypothesis-generating findings warrant prospective validation.

Background Patients with advanced pancreatic ductal adenocarcinoma (aPDAC) often experience general health decline at diagnosis due to a high-symptom burden. The optimal management of symptoms and/or poor performance status (PS) in these patients remains an unmet medical need. Patients and Methods In this multicenter study, patients with PS[≥]2 and pathologically confirmed or imaging-suspected aPDAC were included at first oncology visit in a personalized 14-day emergency integrative supportive care program (14-EISCP) to manage pain, nutrition, diagnostics, and stenting procedures. The primary endpoint was the 14-EISCP success in feasibility of planned procedures and clinical benefit defined as post-EISCP PS[≤]1, [≥]5 points improvement in fatigue, pain, global health-related quality of life (HRQoL) scores (EORTC QLQ-C15-PAL), or chemotherapy initiation within 30 days. Results A total of 106 patients were included; 93 evaluable patients considered for primary endpoint analysis (median age: 76 years [68-80], PS3: 20.9%, metastases: 61.3%). The median overall survival was 4.1 months (IC95% 2.6-5.6). The 14-EISCP was successful in 59.1% (n=55) of patients, meeting the primary objective (clinically relevant). The 14-EISCP feasibility was achieved in 70.9% of cases. Post-EISCP clinical benefit was observed in 79.6% of patients, with PS improvement to 0/1 in 13.2%, HRQoL improvement in 23.9%, and chemotherapy initiation [≤]30 days in 73.1%. Among evaluable patients, 17.2% received mFOLFIRINOX or gemcitabine-nab-paclitaxel, 35.4% received FOLFOX, 25.3% had gemcitabine or 5-fluorouracil alone, and 22.2% received best supportive care. In patients with PS2 at baseline, the administration of doublet/triplet chemotherapy was associated with improved overall survival compared to single-agent. Discussion These results offer a promising framework for improving outcomes in aPDAC patients, bridging the gap between symptom management and systemic therapy administration. Conclusions In patients with PS[≥]2 and aPDAC, the personalized 14-EISCP was feasible and lead to meaningful clinical benefit, allowing doublet or triplet chemotherapy in half the patients.

Background: Trastuzumab deruxtecan (T-DXd) is active in HER2-expressing solid tumours, but trials excluded HER2 immunohistochemistry (IHC) 1+ disease, and data in pretreated ovarian cancer are lacking. We evaluated real-world T-DXd activity and genomic correlates in pretreated ovarian cancer, predominantly high-grade serous (HGSOC). Methods: HER2 expression was assessed in an unselected ovarian cancer cohort (N=74). Fifteen patients receiving off-label T-DXd (14 HGSOC, 1 clear cell; IHC 1+ to 3+) had HER2 status centrally confirmed using gastric-type criteria. Activity was assessed by intra-patient growth modulation index (GMI; progression-free survival [PFS] on T-DXd divided by PFS on the prior line; [≥] 1.33 considered meaningful). Patients on treatment at data cut-off were censored. Objective response (RECIST 1.1) was assessed centrally where imaging was available (n=8). Results: Of the 40 HER2-expressing tumours, 15 received T-DXd, limited mainly by reimbursement. Among 14 evaluable patients (median 5 prior lines), 9 reached a GMI [≥] 1.33 (median 1.69); 8 remained on treatment at cut-off, making durability preliminary. Confirmed partial responses occurred across the HER2 spectrum. Benefit was independent of homologous-recombination (HR) status: one HR-proficient, CCNE1-wild-type patient achieved prolonged control and was rendered disease-free after radiotherapy to an oligoprogressive lesion. Exploratory analysis showed all four evaluable CCNE1-amplified tumours had reduced or non-durable benefit. Conclusions: T-DXd shows preliminary, clinically meaningful activity in HER2 IHC 1+ ovarian cancer independent of HR status. CCNE1 amplification may attenuate benefit, a candidate biomarker for WEE1-inhibitor combinations. Approval restricted to IHC 3+ disease would exclude most responders in this cohort. Prospective validation is required.

Purpose: Pathogenic or likely pathogenic (P/LP) variants are increasingly identified in genes more commonly associated with adult-onset cancer predisposition, but their prevalence and relevance to children who present with cancer remain unclear. Methods: We retrospectively analyzed 1,280 consecutive pediatric patients with cancer who underwent clinical germline sequencing, using a virtual panel, from 2021 to 2024. Genes with P/LP variants were categorized as aoCPG or pediatric-onset cancer predisposition genes (poCPG) according to cancer risk before age 18 years and pediatric surveillance recommendations. Variant relevance was adjudicated using tumor diagnosis/histopathology, immunohistochemistry, and tumor molecular features and classified as primary, secondary, or indeterminate. Results: Among 1,280 patients, 197 (15.4%) harbored 211 P/LP variants across 54 genes. Sixty-six variants (31.3%) occurred in aoCPG, 87 (41.2%) in poCPG, and 58 (27.5%) were heterozygous variants in autosomal recessive genes. Among adult-onset variants, 7 (10.6%) were primary, 54 (81.8%) secondary, and 5 (7.6%) indeterminate. Among pediatric-onset variants, 77 (88.5%) were primary and 10 (11.5%) secondary. Six patients (3 adult-onset variants; 3 pediatric-onset variants) received targeted therapy informed by germline/somatic sequencing results. Conclusion: In pediatric oncology, most variants in aoCPG are secondary rather than tumor-related findings. Tumor-informed interpretation, beyond variant classification, may improve reporting, counseling, and therapeutic decision-making

Background. Duodenal adenocarcinoma (DA) is a rare gastrointestinal malignancy with limited DA-specific evidence on the prognostic role of perineural invasion (PNI) and the performance of AJCC 8th-edition staging. We described PNI, AJCC 8 discrimination, and adjuvant-chemotherapy subgroup associations in a single-center cohort. Methods. We retrospectively analyzed 51 patients with curatively resected, histologically invasive DA (2013-2025). Overall survival (OS) and disease-free survival (DFS) were estimated by Kaplan-Meier analysis; prognostic associations by Cox regression. Model discrimination was quantified by the C-index; adjuvant-chemotherapy associations were explored across pre-specified subgroups. Analyses were exploratory and hypothesis-generating. Results. Median follow-up was 34.9 months; 26 patients (51%) died and 32 (63%) recurred, with the highest recurrence frequency 6-12 months after surgery. AJCC 8 staging discriminated modestly (C-index 0.595); no adjacent stage pair differed significantly after Bonferroni correction (minimum raw pairwise P = 0.051). Among candidate factors, PNI had the largest effect estimate (univariable HR 2.08, 95% CI 0.88-4.90, P = 0.095) and the largest incremental discrimination when added to a stage + T + N base model (delta C-index +0.062; likelihood-ratio P = 0.145), exceeding the increments from tumor size (+0.046), differentiation (+0.034), and sex (+0.016). Adjuvant chemotherapy was associated with hazard-ratio reductions in PNI-positive (HR 0.19, 95% CI 0.02-1.59), stage III (HR 0.36, 95% CI 0.12-1.15), and node-positive (HR 0.36, 95% CI 0.12-1.15) subgroups; none reached statistical significance, consistent with limited power in subgroups of 8-22 patients. Conclusion. In this small single-center cohort, PNI showed the largest prognostic effect estimate among candidate variables and the largest incremental discrimination beyond AJCC 8 stage, although neither reached statistical significance and AJCC 8 discriminated only modestly. These hypothesis-generating findings - directionally concordant with larger published DA series - support formal evaluation of PNI as a stratification variable in multicenter cohorts and in individual-patient-data meta-analyses of duodenal adenocarcinoma, rather than a change in current practice.

Introduction Stark disparities in endometrial cancer (EC) risk and mortality exist between non-Hispanic Black and White women, with Black women experiencing higher incidence and worse survival. This disparity has been attributed to biological and socioeconomic factors, though how these factors interact to influence EC disparities remains unclear. This study modeled EC outcomes using race, area-level socioeconomic deprivation, clinical phenotypes, genetic ancestry, and molecular alterations. Methods We identified 281 cases of EC diagnosed from 2013-2023 in women who underwent clinical genomic sequencing as part of routine care across multiple Northwell Health sites. We estimated genetic ancestry, oncogenic alterations in 324 genes, microsatellite instability, and molecular classification. Geocoded patient addresses were used to derive the state-level Area Deprivation Index to estimate socioeconomic deprivation. Results African ancestry patients were enriched for high-grade disease (89% vs 64%), serous histology (57% vs 26%), and the TP53-mutant molecular classification (71% vs 51%) compared to European ancestry patients (p-value<0.05). Socioeconomic deprivation quintiles were associated with race, with more deprived quintiles enriched for Black patients (p-value<0.001). Both race and genetic ancestry, but not area-level deprivation, were independently associated with differences in progression-free survival. TP53 mutations were enriched in African ancestry patients, while KRAS, PTEN, and ARID1A mutations were enriched in European ancestry patients (q<0.10). Cox proportional hazards modeling, adjusting for these factors, showed that African ancestry patients had worse progression-free survival (HR 1.91, p-value<0.05). Conclusion Our findings indicate that EC disparities persist after adjusting for socioeconomic, clinical, and molecular factors, highlighting the need to further investigate additional drivers of disparity.

Chemotherapy-induced peripheral neuropathy (CIPN) is a common neurotoxicity of cancer treatment with limited diagnostic, monitoring, and treatment options. Neurofilament light chain (NfL) is an axonal cytoskeletal protein released during neuroaxonal injury and a promising biomarker of CIPN, but prospective evidence for NfL as a marker of CIPN from vincristine-containing lymphoma chemotherapy treatment remains limited. To fill this gap, we conducted a pragmatic single-center prospective observational cohort study of adults with non-Hodgkin lymphoma (NHL) receiving first-line vincristine-containing chemotherapy to evaluate NfL dynamics across multiple pre-cycle visits and assess 68 relationships with patient-reported and clinician-graded neuropathy measures. We followed 25 participants during 4-6 months of chemotherapy, and a small subset of those participants (n=6) for 24-42 months post-chemotherapy. Serial plasma NfL was measured and CIPN symptoms were assessed using patient- and clinician-reported measures. Longitudinal changes were analyzed using mixed-effects models. Plasma NfL increased relative to pre-cycle1 at all timepoints (all p<0.001), increasing more than threefold by pre-cycle4. Patient-reported CIPN scores and clinician-graded neuropathy also increased during treatment. Exploratory pooled visit-level analyses showed a modest NfL-CIPN association (Spearman {rho}=0.393, p=0.004), while timepoint-specific, lagged, and post hoc sensitivity analyses suggested potential to predict persistent CIPN symptoms from early NfL concentrations. To our knowledge, these findings provide the first prospective evidence that NfL is sensitive to vincristine exposure in adults with NHL and may complement patient-reported symptom assessment, clinician grading, and dose-modification context in future CIPN monitoring studies.

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.

Background: GBM is one of the most common and most aggressive brain tumors in adults, and upfront standard of care treatment has limited efficacy. Immune checkpoint inhibitor strategies have significantly improved outcomes in various solid tumors but have not proven effective in GBM, suggesting other strategies may be needed to realize their full potential. Methods: GBM patients were treated with upfront standard of care chemoradiation with temozolomide and pembrolizumab, followed by adjuvant temozolomide and pembrolizumab for six nine-week cycles. Depending on production of sufficient vaccine, patients were randomized into HSPPC-96 vaccine or placebo group (q4 weeks) while those with failed vaccine production continued on study unblinded as an ancillary group. The primary objective was overall survival at one year, and secondary endpoints were progression-free survival at six months, overall and progression-free survival, radiographic response, and tolerability by patient-reported outcomes and adverse event documentation. Results: 90 patients were screened, 32 were treated (8 vaccine, 9 placebo, 15 ancillary), and 26 were evaluable for radiographic responses prior to accrual termination. The study did not meet its primary endpoint of overall survival at one year (65.5% in vaccine group, 75% in placebo). Progression-free endpoints were mildly improved in the vaccine group but were not significant, and response rates were not significantly different. The regimen was well-tolerated and safe. Conclusions: Though limited by early discontinuation, these findings do not support the combination of pembrolizumab and HSPPC-96 vaccine with standard of care therapy. Trials Registration: ClinicalTrials.gov identifier: NCT03018288

Background: Acral lentiginous melanoma (ALM) is the predominant melanoma subtype in East Asian populations, accounting for roughly 50 to 58% of cases, compared with 2 to 3% in populations of European ancestry. ALM is genomically and biologically distinct from sun-exposed cutaneous melanoma, and East Asian and acral patients were markedly under-represented in the pivotal antiPD1 registration trials. At the time this study was designed, no prospective trial had evaluated a checkpoint inhibitor specifically in ALM. We conducted a phase II trial to estimate the activity of pembrolizumab in this population. Methods. In this single centre, single arm, open label phase II trial, adults with metastatic or locoregionally advanced inoperable ALM who were naive to antiPD1 or antiPDL1 therapy received pembrolizumab 200 mg intravenously every 3 weeks until progression, unacceptable toxicity, or withdrawal. The primary endpoint was objective response rate (ORR) by RECIST 1.1. Secondary endpoints included duration of response (DoR), clinical benefit rate (CBR), progression-free survival (PFS), overall survival (OS), and safety (CTCAE v4.0). A Simon minimax two-stage design (P0=0.10, P1=0.30, power=80%) planned enrolment of up to 28 patients. Results. Between February 2017 and June 2019, 9 patients were enrolled before recruitment was halted for slow accrual, the interval availability of reimbursed pembrolizumab, and a low observed response signal. Median age was 72 years (range 48 to 78); 6 (67%) were male; all had ECOG performance status 0 and metastatic disease; 7 (78%) had received prior therapy. One patient achieved a partial response (ORR 11.1%, 95% CI 0.0 to 31.6%), with a DoR of 19 months; 3 had stable disease and 4 progressed. CBR (response or stable disease greater than or equal to 12 weeks) was 44.4% (95% CI 12.0 to 76.9). At a median follow-up of 7.6 months, median PFS was 3.4 months (95% CI 1.4 to 21.3) and median OS was 7.6 months (95% CI 2.0 to 34.3). Two grade 3 adverse events occurred, both assessed as unrelated to study drug; no treatment-related grade 3 or above events were recorded. In an exploratory analysis, an LDH to upper limit of normal ratio >1.5 was associated with worse OS (median 4.3 vs 26.5 months; HR 4.58, 95% CI 0.82 to 25.7; log-rank p=0.06). Conclusions. Recruitment was constrained by disease rarity and a shifting reimbursement landscape, and the trial closed before completing stage 1. Within these limitations, single-agent pembrolizumab showed only modest activity in advanced ALM, consistent with the limited efficacy subsequently reported in larger contemporary acral melanoma cohorts. The exploratory association between elevated LDH ratio and poorer survival warrants prospective evaluation.

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.

Introduction: This study aimed to provide population level survival trends during the era in which new systemic therapies transformed treatment guidelines for metastatic cancer, as well as insights on the real world use of these treatments and associated survival. Methods: Adults diagnosed with synchronous metastatic solid cancer in 2008 until 2022 (22 cancer types) were identified from the Netherlands Cancer Registry. Median overall survival (OS) was assessed by five year diagnostic period. For 2018 until 2022, systemic therapy use in any treatment line was analyzed and survival percentiles within treatment and cancer types were estimated with Kaplan Meier survival analyses. Results: Median OS in the overall cohort (n=280,419 patients) improved from 6 to 8 months between the period 2008 until 2012 and 2018 until 2022. Among patients diagnosed in 2018 until 2022, 15% received immunotherapy, 15% targeted therapy, 29% chemotherapy and/or traditional hormone therapy only, and 39% no systemic therapy. In some cancer types, a relatively large proportion of treated patients had longterm survival (e.g., immunotherapy in melanoma: p50 = 67 months). Other cancer types had a smaller subset of treated patients (p10 and p25) with substantially better outcomes than the median (e.g., targeted therapy in NSCLC: p50 = 22 months, p10 = 96 months). Conclusion: Population level survival for patients with synchronous metastatic solid cancer has modestly improved over time. The marked survival heterogeneity within cancer and treatment types highlights both the potential and uncertainty associated with (novel) treatments. Improved prediction of treatment effects and clear communication regarding survival expectation remain critical. Presenting multiple survival scenarios over median survival alone can support decision making.

Purpose: Glioblastoma (GBM) remains associated with poor outcomes, with most recurrences occurring within the high-dose radiation field, suggesting persistent radioresistance. Exportin 1 (XPO1) inhibition with Selinexor has demonstrated radiosensitizing effects in preclinical models. We conducted a phase I trial to evaluate the safety, tolerability, and preliminary efficacy of Selinexor in combination with standard chemoradiation for newly diagnosed GBM. Methods: This investigator-initiated phase I dose-escalation trial (3+3 design) enrolled adults with newly diagnosed GBM or gliosarcoma. Patients received standard radiotherapy (60 Gy in 30 fractions) with concurrent temozolomide and escalating doses of Selinexor. Three dose levels were evaluated: 80 mg weekly (weeks 1, 2, 4, 5); 60 mg twice weekly (weeks 1, 2, 4, 5); and 60 mg twice weekly (weeks 1-6) throughout radiotherapy. The primary endpoint was determination of the maximum tolerated dose (MTD) based on dose-limiting toxicities (DLTs). Secondary endpoints included progression-free survival (PFS), overall survival (OS), patterns of failure, and patient-reported outcomes (MDASI-BT). Results: Eleven patients were enrolled. Median age was 58 years, and median KPS was 90. The MTD was established at Selinexor 60 mg twice weekly during weeks 1, 2, 4, and 5 of chemoradiation. Dose level 3 exceeded the MTD with two DLTs. Treatment compliance was high, with minimal missed radiotherapy fractions. Median PFS was 15.9 months (95% CI, 6.2 28.5), and median OS was 17.4 months (95% CI, 14.1 not reached). Most recurrences were central (5/6 evaluable patients). Notably, multiple cases of delayed pseudoprogression were observed at 5, 9, 10, and 23 months post-radiotherapy. Patient-reported symptom burden remained stable over time. Conclusions: Selinexor can be safely combined with standard chemoradiation in patients with newly diagnosed GBM, with an MTD of 60 mg twice weekly during select treatment weeks. Preliminary efficacy signals and an increased incidence of delayed pseudoprogression suggest a potential radiosensitizing effect. These findings support further investigation of Selinexor in larger, prospective studies.

Background The clinical significance of clonal hematopoiesis of indeterminate potential (CHIP) in melanoma remains incompletely defined, particularly with respect to CHIP genotype, clone size, and somatic mutations (e.g BRAF mutations). We integrated human cohort data and a syngeneic melanoma mouse model to evaluate whether CHIP is associated with melanoma risk, tumor growth, and differential clinical outcomes. Methods We analyzed CHIP prevalence and survival in a large treatment-unselected melanoma cohort (n=2,480), evaluated tumor growth in a syngeneic BRAF-mutant (BRAFmut) melanoma murine model of TET2-CHIP and DNMT3A-CHIP, and assessed survival outcomes in an immune checkpoint inhibitor (ICI)-treated advanced melanoma cohort (n=361). Associations with progression-free survival (PFS) and overall survival (OS) were evaluated using Kaplan-Meier analyses and multivariable Cox proportional hazards models. Results CHIP was enriched among patients with treatment-unselected melanoma compared with age/sex-matched healthy controls, and larger CHIP clone size showed an age-adjusted association with inferior OS. In a syngeneic BRAFmut melanoma murine model, TET2-CHIP, but not DNMT3A-CHIP, was associated with significantly increased primary melanoma tumor growth. Among patients with ICI-treated advanced melanoma, CHIP was associated with worse OS compared with patients without CHIP. TET2-CHIP had the strongest adverse association with survival, whereas DNMT3A-CHIP was not significantly associated with PFS or OS. Conclusions CHIP is enriched in melanoma and exploratory analyses demonstrate genotype-specific differences in melanoma tumor growth and clinical outcomes. These findings support further investigation of genotype-specific CHIP profiling as a potential biomarker for melanoma risk stratification and immunotherapy outcomes.

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.

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.

Purpose: Exceptional responses are frequent in patients with HER2-positive (HER2+) metastatic breast cancer (MBC), but predictive biomarkers are lacking. We aimed to investigate the association between detection of minimal residual disease (MRD) via circulating tumor DNA (ctDNA) and exceptional response to first-line HER2 targeted therapy for MBC. Patients and Methods: We identified exceptional (real-world progression-free survival [rwPFS] [&ge;]3 years) and conventional (rwPFS <3 years) responders treated with first-line HER2 targeted therapy for HER2+ MBC and plasma collected at landmark timepoints (e.g., baseline, year [Y] 1, Y2, Y3, at progression). We generated personalized, tissue-informed MRD assays using MAESTRO mutation enrichment sequencing in a pooled format. The primary endpoint was the association between MRD status at Y1 and rwPFS. Results: Of 70 patients, 63 (90%) (40 exceptional and 23 conventional responders) had sufficient samples and successful assay design; MAESTRO was run on 149 samples. A median of 1,823 (range 387-5,000) tumor-specific mutations were tracked per patient. MRD was detected in 49 (32%) samples (median tumor fraction [TFx] 936 ppm; range 3.8-164,068 ppm); 15 (31%) samples had TFx <100 ppm. MRD was associated with outcomes: 0/27 [0%] exceptional versus 9/12 [75%] conventional responders (p<0.001) had detectable MRD at Y1. Exceptional responders who remained progression-free were always MRD-negative (n=30) or cleared MRD by Y1 (n=3). Six exceptional responders experienced late progression, and four of them had a Y3 sample: MRD was detected in three patients (lead time range 2.77-13.47 years), one patient had breast-only progression and was MRD-negative. Conclusions: MRD status at key timepoints is associated with exceptional response and late distant progression, supporting prospective clinical trials implementing MRD testing with highly sensitive tumor-informed assays to guide treatment de-escalation.

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.

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.

Accurate prediction of ex vivo drug sensitivity in acute myeloid leukemia (AML) patients from transcriptomic data is a critical challenge for precision oncology. Existing computational approaches have explored uncertainty quantification in cancer drug response prediction primarily using cell line data, while patient-level AML models typically rely on heuristic confidence measures rather than statistically calibrated uncertainty estimates. Here, we present a framework applying split conformal prediction to patient-level AML drug response modeling using the BeatAML 2.0 cohort. We trained Elastic Net and XGBoost regressors on bulk RNA-seq gene expression profiles from 318 AML patients, analyzing 34,764 patient-drug observations across 122 compounds. Baseline models achieved median Pearson R values of 0.291 (Elastic Net) and 0.281 (XGBoost) across 122 drugs. Wrapping these models with split conformal prediction yielded well-calibrated prediction intervals across three confidence levels: empirical coverages of 81.4%, 90.7%, and 95.5% against nominal targets of 80%, 90%, and 95%, respectively. Analysis of prediction interval widths revealed substantial drug-class-specific uncertainty patterns, with HDAC and BCL-2 inhibitors exhibiting markedly higher uncertainty than MDM2 inhibitors, suggesting a potential association between transcriptomic predictability and drug mechanism of action, although several drug classes were represented by only a small number of compounds. Predictive uncertainty was not significantly associated with ELN2017 molecular risk classification (Kruskal-Wallis p=0.395) or NPM1 mutation status (p=0.788). These results demonstrate that statistically valid uncertainty quantification can be achieved for patient-level AML drug response prediction despite substantial biological heterogeneity. to the best of our knowledge, no published study has applied split conformal prediction to patient-level ex vivo drug sensitivity prediction in the BeatAML cohort, providing a principled alternative to heuristic confidence scoring approaches.