Early Detection Of Relapse Research Articles

Soluble B-cell maturation antigen levels for disease monitoring in oligo- and non-secretory relapsed multiple myeloma

Soluble B-cell maturation antigen (sBCMA) is overexpressed on multiple myeloma (MM) cells. We investigated whether sBCMA levels correlated with other myeloma tumor volume indicators and its utility in monitoring oligo-secretory/non-secretory (O-S/Non-S) MM. In 115 patients with newly diagnosed MM, sBCMA was compared with M-protein levels, bone marrow plasma cells (BMPCs), circulating tumor cells (CTCs), and total diffusion volume (tDV; estimated by whole-body diffusion-weighted magnetic resonance imaging) at diagnosis. sBCMA levels increased significantly with International Staging System stage, chromosome 1q21 gain/amplification and CTC levels. sBCMA also correlated strongly with %BMPC (r = 0.65), moderately with tDV (r = 0.55) and paraprotein levels (involved immunoglobulin in IgG and IgA subtypes, r = 0.44 and 0.4; involved free light-chain levels in light-chain-only MM, r = 0.61, all P < 0.05). Longitudinal changes in sBCMA were consistent with disease status in both 17 O-S/Non-S and other secretory MM cases. Furthermore, sBCMA levels increased as early as 6 months pre-relapse in almost all O-S/Non-S relapsed patients. Thus, sBCMA correlates strongly with total tumor volume in MM, as assessed using different modalities. We suggest that sBCMA is useful, not only for monitoring responses in patients with O-S/Non-S MM but also for early relapse detection and prediction.

The Role of HE4 in the Follow-Up of Advanced Ovarian, Fallopian Tube, and Primary Peritoneal Cancer—CEEGOG OX-01 Study

Background: Ovarian, fallopian tube, and primary peritoneal cancers often share clinical characteristics and are typically diagnosed at advanced stages due to nonspecific symptoms. The utility of tumor markers, particularly CA125 and HE4, in the diagnosis and follow-up of these cancers remains an area of active investigation. Objectives: The CEEGOG (Central and Eastern European Gynecologic Oncology Group) OX-01 study aimed to evaluate HE4’s role alongside CA125 in follow-up for advanced-stage ovarian, fallopian tube, and primary peritoneal cancers. It assessed the potential for detecting recurrence using marker elevation and imaging methods, examining the necessity of dynamic monitoring and current cut-off values’ accuracy for early relapse detection. Methods: In this multicenter prospective cohort study, 117 eligible patients with Stage III–IV cancers were included. Patients had elevated CA125 or HE4 at diagnosis and achieved complete remission after first-line treatment. HE4 and CA125 levels were monitored every 3–4 months in the first two years and every six months thereafter. CT scans were performed if markers exceeded set thresholds or increased by over 20%. Results: During a median follow-up of 13.7 months, 73% of patients relapsed. Median HE4 levels were significantly higher in relapsed patients. A 10 IU/mL increase from baseline in CA125 had a sensitivity of 83% and specificity of 93%, while a 15 pmol/L increase in HE4 had a sensitivity of 74% and specificity of 92% for predicting relapse up to three months before CT scan detection. Conclusions: The study found that dynamic changes in HE4 and CA125 levels, rather than predefined cut-off values, are crucial for early relapse detection. These markers may offer a significant lead time over imaging, potentially enabling earlier intervention. Further research is needed to validate these findings.

EVALUATION OF THE EFFICACY OF ASPARAGINASE ADDED TO CHEMOTHERAPEUTIC DRUG REGIMEN IN ACUTE LYMPHOBLASTIC LEUKEMIA BY MINIMAL RESIDUAL DISEASE MEASUREMENT

B-ALL is the most common subtype of childhood Acute Lymphoblastic Leukemia (ALL), affecting approximately 85% of children worldwide. Minimal Residual Disease (MRD) monitoring during treatment of ALL is important for the prognosis of the disease. MRD monitoring, which enables early detection of relapse, determination of risk percentage and understanding the effectiveness of treatment, can be performed with multiple methods such as flow cytometry, qRT-PCR and NGS. Asparaginase is an enzyme that has been used in the treatment of ALL since the 1960s, converting asparagine to ammonia and aspartic acid, lowering serum asparagine levels and causing the death of malignant cells. In this study, we investigated the effect of asparaginase added to the ALL IC BFM 2009 treatment protocol in 62 B-ALL patients aged 0-18 years with MRD monitoring by flow cytometry. In our study, Escherichia Coli (E.Coli.) asparaginase was used primarily and PEG-asparaginase was used after allergy development. The effect of asparaginase on treatment was evaluated by evaluating asparagine concentration and asparaginase activity measured at TP1 (4th week after induction treatment) together with MRD levels. As a result of the study, it was observed that the added asparaginase positively affected the treatment and increased the negativity in MRD levels.

BCMA-Directed MRD Detection as a Predictor of Relapse after BCMA CAR T in Multiple Myeloma

Background: Recent approvals of chimeric antigen receptor T-cells (CAR T) and bispecific antibody therapies offer new hope for relapsed refractory multiple myeloma (RRMM) patients, with superior efficacy over standard regimens observed in clinical trials. However, relapse after BCMA-directed therapy is common and requires further investigation. Patients and Methods: We conducted a retrospective cohort study on 57 RRMM patients treated with BCMA-directed CAR T. Only the patients who had an initial response and lost BCMA-expressing identified PC following CAR T infusion at Day 30 were included in the analysis. Multicolor flow cytometry (MFC) to detect BCMA + plasma cell (PC) re-emergence was performed on bone marrow samples at defined intervals and clinical responses were assessed using International Myeloma Working Group criteria. Results: The majority of patients achieved undetectable BCMA on MFC post-infusion, with subsequent BCMA+ PC re-emergence observed in 55% of cases. Notably, 91% of patients experiencing clinical relapse showed BCMA+ PC re-emergence, often preceding relapse. Early relapse (<6 months) was associated with earlier BCMA re-emergence. Conclusion: Early BCMA+ PC re-emergence may serve as a prognostic marker for clinical relapse post-BCMA CAR T therapy. Monitoring BCMA+ PC levels via MFC offers potential for early relapse detection and informed treatment decisions. Further studies, including novel BCMA-directed minimal residual disease (MRD) detection technologies, are warranted to validate these findings and refine RRMM management strategies.

Modeling serum M-protein response for early detection of biochemical relapse in myeloma patients treated with bortezomib, lenalidomide and dexamethasone.

Multiple myeloma (MM) treatment guidelines recommend waiting for formal progression criteria (FPC) to be met before proceeding to the next line of therapy. As predicting progression may allow early switching to next-line therapy while the disease burden is relatively low, we evaluated the predictive accuracy of a mathematical model to anticipate relapse 180 days before the FPC is met. A subset of 470/1143 patients from the IA16 dataset who were initially treated with VRd (Velcade (bortezomib), Revlimid (lenalidomide), and dexamethasone) in the CoMMpass study (NCT01454297) were randomly split 2:1 into training and testing sets. A model of M-protein dynamics was developed using the training set and used to predict relapse probability in patients in the testing set given their response histories up to 12 or more months of treatment. The predictive accuracy of this model and M-protein "velocity" were assessed via receiver operating characteristics (ROC) analysis. The final model was a two-population tumor growth inhibition model with additive drug effect and transit delay compartments for cell killing. The ROC area under the curve value of relapse prediction 180 days ahead of observed relapse by FPC was 0.828 using at least 360 days of response data, which was superior to the M-protein velocity ROC score of 0.706 under the same conditions. The model can predict future relapse from early M-protein responses and can be used in a future clinical trial to test whether early switching to second-line therapy results in better outcomes in MM.

Relapses in canine leishmaniosis: risk factors identified through mixed-effects logistic regression

BackgroundCanine leishmaniosis (CanL), caused by Leishmania infantum, is an important vector-borne parasitic disease in dogs with implications for human health. Despite advancements, managing CanL remains challenging due to its complexity, especially in chronic, relapsing cases. Mathematical modeling has emerged as a powerful tool in various medical fields, but its application in understanding CanL relapses remains unexplored.MethodsThis retrospective study aimed to investigate risk factors associated with disease relapse in a cohort of dogs naturally infected with L. infantum. Data from 291 repeated measures of 54 dogs meeting the inclusion criteria were included. Two logistic mixed-effects models were created to identify clinicopathological variables associated with an increased risk of clinical relapses requiring a leishmanicidal treatment in CanL. A backward elimination approach was employed, starting with a full model comprising all potential predictors. Variables were iteratively eliminated on the basis of their impact on the model, considering both statistical significance and model complexity. All analyses were conducted using R software, primarily employing the lme4 package, and applying a significance level of 5% (P < 0.05).ResultsThis study identified clinicopathological variables associated with an increased risk of relapses requiring a leishmanicidal treatment. Model 1 revealed that for each 0.1 increase in the albumin/globulin ratio (A/G) ratio, the odds of requiring treatment decreased by 45%. Conversely, for each unit increase in the total clinical score (CS), the odds of requiring treatment increase by 22–30%. Indirect immunofluorescence antibody test (IFAT) was not a significant risk factor in model 1. Model 2, incorporating individual albumin and globulins values, showed that dogs with high IFAT titers, hyper beta-globulinemia, hypoalbuminemia, anemia, and high CS were at increased risk of relapse. Both models demonstrated a good fit and explained a substantial amount of variability in treatment decisions.ConclusionsDogs exhibiting higher CS, dysproteinemia, anemia, and high IFAT titers are at increased risk of requiring leishmanicidal treatment upon clinical relapse in CanL. Regular monitoring and assessment of risk factors prove essential for early detection of relapses and effective intervention in CanL cases. The contrasting findings between the two models highlight the complexity of aspects influencing treatment decisions in this disease and the importance of tailored management strategies to improve outcomes for affected dogs.Graphical

Performance Characteristics of Next-Generation Sequencing–Based Engraftment Monitoring and Microchimerism Detection in Allogeneic Hematopoietic Cell Transplantation: A Practical Approach for Clinical Assay Validation

Chimerism analysis by next-generation sequencing (NGS) is an emerging method for engraftment monitoring after allogeneic hematopoietic cell transplantation. A high-sensitivity method is required for the detection of microchimerism (<1% chimerism), which may have clinical utility in early relapse detection, allograft monitoring in organ transplantation, and other allogeneic cellular therapies (such as microtransplantations). As more clinical laboratories adopt this method, a thorough assessment of performance is needed. This study evaluated one such NGS-based assay that uses both single-nucleotide polymorphisms and insertions/deletions as genetic markers. An assessment of accuracy, linearity, sensitivity, and reproducibility was performed. Analytical sensitivity was 0.2% donor for single donor and 0.5% donors for double donors. The assay showed a high degree of reproducibility over a full range of chimerism. Comparison to short-tandem-repeat (STR) PCR showed high concordance; yet <5% chimerism was consistently detected by NGS, but not by STR-PCR. Comparison to real-time quantitative PCR showedhigh concordance, but with lower correlation in the midrange (40% to 60% chimerism). Overall, the assay showed consistent performance with high sensitivity and accuracy compared with STR-PCR and real-time quantitative PCR across a full range of chimerism in the setting of single-donor and multidonor transplantations. In addition, criteria for quality metrics were established for sequencing performance and data analysis and considerations made for clinical laboratory validation of NGS-based chimerism assay andanalysis software.

Established a therapeutic response prediction model in metastatic gastric cancer by liquid biopsy

AbstractThis study by Okuno et al. successfully identified eight exo‐miRNAs through exosome‐based discovery and established an exo‐miRNA‐based liquid biopsy assay for predicting therapeutic response in metastatic gastric cancer (mGC). Exosomes, a subpopulation of extracellular vesicles originating from endosomes, play a crucial role in this context. Liquid biopsy, analyzing blood for circulating tumor cells, extracellular vesicles, or cell‐free nucleic acid, has revolutionized cancer diagnosis and monitoring. It significantly contributes to early detection, staging, and relapse detection in various cancers. Numerous studies have highlighted the clinical significance of miRNA and lncRNA within extracellular vesicles. The authors developed a response‐prediction model for chemo‐responsiveness in mGC patients. This study's model predicts responses robustly, demonstrating its potential efficacy in clinical practice. It offers a non‐invasive and accessible method for therapeutic response prediction, crucial for precision medicine in mGC. Successful translation of these findings into clinical applications promises substantial benefits for patient care.

The Role of Semaphorin 6D (Sema6D) in Non-Muscle-Invasive Bladder Cancer-A Preliminary Study on Human Plasma and Urine.

The incidence of bladder cancer worldwide in the last three decades has been increasing in both men and women. So far, there is no established non-invasive bladder cancer biomarker in daily clinical practice. Semaphorin 6D (sema6D) is a transmembrane protein that belongs to the class VI semaphorins. The aim of this study was to evaluate for the first time the potential role of sema6D in bladder cancer. The study group consisted of 40 patients with non-muscle-invasive bladder cancer (NMIBC) and the control group of 20 patients without malignancies. There was a statistically significantly higher urinary sema6D concentration in patients than controls (p < 0.05) but no significant difference in plasma 6D. There were no statistically significant differences in urinary or plasma concentration of sema6D between low- or high-grade cancer and according to the tumor stage in TNM classification. There was a statistically significant negative correlation between plasma sema6D and age of patients (R = -0.6; p = 0.019). Plasma sema6D does not seem to be useful in the clinical practice at this point. However, the urinary sema6D concentration could potentially serve as a marker of NMIBC used for diagnostic purposes, monitoring, and early relapse detection or the assessment of the treatment efficacy. Urinary sema6D is probably not associated with the grading or staging of NMIBC, so it cannot be used for the prediction of disease prognosis.

Dynamic Changes in Circulating Methylated Markers in Response to Antitumor Therapy of Rectal Cancer.

Rectal cancer (RC) occupies a leading position in the structure of oncological morbidity and mortality. Aberrant methylation of tumor-suppressor genes and hypomethylation of retrotransposons were shown to be detectable in cell-free DNA, circulating in the blood (cfDNA) of cancer patients, indicating the possibility to use them as diagnostic and prognosis markers. Evaluation of the changes in the methylation level of LINE-1 elements and SEPTIN9 and IKZF1 genes in the cell-surface-bound cfDNA (csb-cfDNA) from the blood of RC patients after antitumor therapy at a long-term follow-up. Blood samples were obtained from RC patients (n = 25) before treatment, after preoperative chemotherapy (3 courses according to the XELOX scheme), 10-15days after surgery, and every 3months during 12months of dynamic observation. The methylation level of LINE-1, SEPTIN9, and IKZF1 in the csb-cfDNA was evaluated by quantitative methyl-specific PCR. The LINE-1 methylation level in the csb-cfDNA increased 1.6 times in RC patients after chemotherapy and 3 times after tumor resection versus methylation level before therapy. The SEPTIN9 gene methylation level in the csb-cfDNA decreased by 1.7 times in RC patients after chemotherapy and by 2.3 times after tumor resection compared with the values before the treatment. The IKZF1 gene methylation level decreased by 2 times in RC patients after combined therapy. Notably, all patients with relapses (n = 5) showed an increase in methylation level for the SEPTIN9 and IKZF1 genes and a decrease of methylation level for the LINE-1 elements by 2 times or more in comparison with the level 10-15days after surgery. There were no changes in the circulating SEPTIN9, IKZF1, and LINE-1 methylation levels during the 12-month follow-up period after the combined therapy of RC patients (n = 20) without relapses. The results indicate that SEPTIN9, IKZF1, and LINE-1 methylation levels in the csb-cfDNA are potential markers of the effectiveness of antitumor therapy and early detection of relapse in RC patients.

Unraveling malignant phenotype of peritumoral tissue: transcriptomic insights into early-stage breast cancer

BackgroundEarly-stage invasive ductal carcinoma displays high survival rates due to early detection and treatments. However, there is still a chance of relapse of 3–15% after treatment. The aim of this study was to uncover the distinctive transcriptomic characteristics and monitoring prognosis potential of peritumoral tissue in early-stage cases.MethodsRNA was isolated from tumoral, peritumoral, and non-tumoral breast tissue from surgical resection of 10 luminal early-stage invasive ductal carcinoma patients. Transcriptome expression profiling for differentially expressed genes (DEGs) identification was carried out through microarray analysis. Gene Ontology and KEGG pathways enrichment analysis were explored for functional characterization of identified DEGs. Protein-Protein Interactions (PPI) networks analysis was performed to identify hub nodes of peritumoral tissue alterations and correlated with Overall Survival and Relapse Free Survival.ResultsDEGs closely related with cell migration, extracellular matrix organization, and cell cycle were upregulated in peritumoral tissue compared to non-tumoral. Analyzing PPI networks, we observed that the proximity to tumor leads to the alteration of gene modules involved in cell proliferation and differentiation signaling pathways. In fact, in the peritumoral area were identified the top ten upregulated hub nodes including CDK1, ESR1, NOP58, PCNA, EZH2, PPP1CA, BUB1, TGFBR1, CXCR4, and CCND1. A signature performed by four of these hub nodes (CDK1, PCNA, EZH2, and BUB1) was associated with relapse events in untreated luminal breast cancer patients.ConclusionsIn conclusion, our study characterizes in depth breast peritumoral tissue providing clues on the changes that tumor signaling could cause in patients with early-stage breast cancer. We propose that the use of a four gene signature could help to predict local relapse. Overall, our results highlight the value of peritumoral tissue as a potential source of new biomarkers for early detection of relapse and improvement in invasive ductal carcinoma patient’s prognosis.

Personalized cell-free tumor DNA analysis for patients with HNSCC: Liquid biopsy for minimal residual disease detection in head and neck squamous cell carcinoma (LIONESS).

3010 Background: Early relapse and development of metastatic disease are some of the primary reasons for the poor prognosis of patients with head and neck squamous cell carcinoma (HNSCC). We conducted LIONESS, a single-center prospective cohort study to assess ctDNA in plasma and saliva from 76 patients with HNSCC receiving primary surgery with curative intent. Our objectives were to determine whether postoperative ctDNA detection can act as a biomarker for surgical tumor clearance and detection of molecular residual disease (MRD) and to evaluate the potential of tumor-informed ctDNA analysis for early molecular-level detection of relapse or prior to clinically confirmed recurrence. Methods: Plasma and saliva samples from 76 HNSCC patients (37% stage I/II, 63% stage III/IV; 93% p16-negative) were collected pre- and postoperatively and during clinical follow-up. Whole exome sequencing was performed on FFPE tumor tissue. Tumor-specific variants for personalized assay design (RaDaR, NeoGenomics Laboratories) were selected and used in the analysis of serial samples for evidence of MRD. ctDNA levels were correlated to tumor volumes from staging CT, as well as pathological and other clinical parameters. Results: 617 longitudinal plasma and 128 saliva samples were collected pre- and postoperatively and during clinical follow-up (median follow-up time of 805 days). In plasma, ctDNA was detected at a median estimated variant allele frequency (eVAF) of 0.036% (0.000327% - 18.43%). 34% of positive samples had ctDNA levels detected at an eVAF of ≤0.01%. Increased plasma ctDNA levels were detected postoperatively in 96% of cases with confirmed clinical recurrences (21/22) with a median lead time of 160 days (6 – 763 days). Of the remaining 54 patients with no clinically confirmed relapse, ctDNA was detected immediately postop in 7 of them. In 5 patients, adjuvant therapy resulted in persistent ctDNA clearance, while 2 patients are deceased. ctDNA was also detected in baseline saliva samples from patients with HNSCC of various anatomical locations with a 74% overlap with the corresponding plasma ctDNA profiles. There was a strong linear correlation between larger tumor volumes and higher eVAF and a trend towards higher eVAF in cases with regional and distant recurrences in comparison to local relapse. Pathological tumor stage and lymph node involvement were both strongly correlated with preoperative ctDNA shedding. Conclusions: The use of ctDNA detection in surgically treated patients with HNSCC has significant potential to guide treatment decisions, improve disease outcome and potentially spare patients unnecessary, partially invasive interventions during clinical follow-up. Our work demonstrates the feasibility of tumor-informed ctDNA assays for detection of MRD postoperatively and for monitoring for early detection of relapse.

Clinical utility of ctDNA as a tool to detect triple-negative breast cancer relapses: The CUPCAKE trial.

TPS1139 Background: The current follow-up of triple-negative breast cancer (TNBC) patients at high risk of relapse does not involve any blood or imaging monitoring to detect metastases, because of the low sensitivity and specificity of blood and imaging biomarkers in that context. In contrast, ctDNA detection techniques are highly specific, sensitive and can detect a molecular relapse several months before the occurrence of symptoms (1). We hypothesize that the early detection of molecular relapse by ctDNA combined with whole-body mapping of tumor recurrence sites by 68Ga-FAPI-46-PET/CT will enable the detection of relapses when they are still limited in size and number of sites. Detecting oligometastatic relapses could demonstrate a clinical utility by (i) allowing the use of local treatments in addition to systemic treatments; (ii) taking advantage of the higher efficacy of immunotherapy in patients with limited tumor burden and inflammation. Methods: CUPCAKE is a randomized, non-comparative, multicenter trial promoted by Institut Curie (Paris, France), which design is inspired from the Trials WIthin CohortS approach (2). N=450 non-metastatic TNBC patients at high risk of relapse will be included after having signed a written informed consent in a cohort allowing them to be followed by ctDNA monitoring. For each included patient, a ctDNA detection assay (FoundationOne Tracker) will be performed every 3 months, with a turnaround time of less than 3 weeks. When negative, ctDNA detection results will not be disclosed to patients nor clinicians. If, at any timepoint, ctDNA is detected (molecular relapse), patients will be randomized in a 1:1 ratio between the experimental arm (ctDNA-based intervention) and the control arm (no intervention). In the experimental arm, the positive ctDNA result will be disclosed. To locate metastatic foci, patients will be offered to undergo whole-body imaging with 18F-FDG and 68Ga-FAPI-46-PET/CT, in addition to any other workup considered as relevant by their treating physician. If/when a clinical/radiological relapse is observed, systemic or local treatments will be decided by physicians (standard of care). In the control arm, patients and their treating physician will not be made aware of the molecular relapse and will continue the standard surveillance with repeated ctDNA test every 3 months (blinded). At the time of the clinical/radiological diagnosis of relapse, similar procedures will be performed (18F-FDG &amp; 68Ga-FAPI-46-PET/CT). The primary endpoint is overall survival rate at 24 months after the randomization in the experimental arm while the control arm will serve as reference. Secondary endpoints include efficacy criteria like progression-free survival but also clinical features upon radiological/radiological relapse, or performance criteria of 68Ga-FAPI-46 versus 18F-FDG PET/CT. 1. Coombes, Clin Cancer Res. 2019. 2. Relton, BMJ. 2010. Clinical trial information: 06225505.

HERD: A multi-centre prospective cohort study to facilitate early detection of relapse in radically treated, high risk head and neck squamous cell carcinoma.

TPS6128 Background: Head and Neck Squamous Cell Carcinoma (HNSCC) is the 7th most common cancer worldwide with more than 660,000 cases diagnosed annually. Many patients present with locally advanced disease, which despite aggressive multi-modality treatment remains associated with poor survival. Approximately 50% of patients relapse within 2 years, mostly occurring in the first year after treatment. Biomarkers predicting relapse are lacking and there remains no consensus on surveillance, with strategies differing according to local guidelines and recurrence too often detected when not amenable to salvage surgery (estimated to improve survival outcomes in relapsed HNSCC by up to 73%). We hypothesize that risk of relapse relies on a dynamic interplay between the immune profile, tumor microenvironment (TME; elucidated by radiology and tissue-based laboratory imaging), genomic background and clinicopathological characteristics. Our primary objectives are to develop and validate a multi-analyte based risk prediction tool and risk-stratified follow up strategy to enhance detection of early relapse and improve survival. Methods: This multi-center study is prospectively collectingsamples across multiple platforms including imaging, blood, saliva, stool, urine, and tissue from patients with newly diagnosed high risk locally advanced HPV-negative HNSCC planned for radical treatment (either surgery or (chemo)radiotherapy). We aim to recruit 200 patients in 2 stages, including discovery and validation cohorts. Three mechanistic (hypothesis-driven) meta-covariates and five working platform meta-covariates will be analysed to test recurrence prediction. Each meta-covariate represents an integrated risk score from covariate subsets. The 3 hypotheses are H1) combining magnetic resonance parameters of hypoxia and stromal composition with TME changes; H2) capturing the interactions between genomic mutations, immune cells and exosomes within the TME H3) understanding the relationship between micro-organisms and TME. The technical platforms include exosomal analyses, multi-parametric MRI including novel elastography (MRE) and quantitative magnetic susceptibility mapping (QSM) techniques, comprehensive circulating tumour and cell-free DNA analyses to aid detection of minimally residual disease, tissue immune profiling, somatic mutation testing and microbiome analysis. Regression Analysis will be performed by machine-learning with advanced mathematical and Bayesian statistical modelling. Accrual began in October 2023. Clinical trial information: NCT05097625 .

Circulating Tumor DNA as a Complementary Prognostic Biomarker during CAR-T Therapy in B-Cell Non-Hodgkin Lymphomas.

The emergence of CD19-directed chimeric antigen receptor T-cell (CAR-T) therapy has revolutionized the treatment paradigm for R/R B-cell NHLs. However, challenges persist in accurately evaluating treatment response and detecting early relapse, necessitating the exploration of novel biomarkers. Circulating tumor DNA (ctDNA) via liquid biopsy is a non-invasive tool for monitoring therapy efficacy and predicting treatment outcomes in B-NHL following CAR-T therapy. By overcoming the limitations of conventional imaging modalities, ctDNA assessments offer valuable insights into response dynamics, molecular mechanisms of resistance, and early detection of molecular relapse. Integration of ctDNA monitoring into clinical practice holds promise for personalized therapeutic strategies, guiding the development of novel targeted therapies, and enhancing patient outcomes. However, standardization of assay methodologies and consensus on clinical response metrics are imperative to unlock the full potential of ctDNA in the management of B-NHL. Prospective validation of ctDNA in clinical trials is necessary to establish its role as a complementary decision aid.

IMPI: An Interface for Low-Frequency Point Mutation Identification Exemplified on Resistance Mutations in Chronic Myeloid Leukemia

Background: In genomics, highly sensitive point mutation detection is particularly relevant for cancer diagnosis and early relapse detection. Next-generation sequencing combined with unique molecular identifiers (UMIs) is known to improve the mutation detection sensitivity. Methods: We present an open-source bioinformatics framework named Interface for Point Mutation Identification (IMPI) with a graphical user interface (GUI) for processing especially small-scale NGS data to identify variants. IMPI ensures detailed UMI analysis and clustering, as well as initial raw read processing, and consensus sequence building. Furthermore, the effects of custom algorithm and parameter settings for NGS data pre-processing and UMI collapsing (e.g., UMI clustered versus unclustered (raw) reads) can be investigated. Additionally, IMPI implements optimization and quality control methods; an evolution strategy is used for parameter optimization. Results: IMPI was designed, implemented, and tested using BCR::ABL1 fusion gene kinase domain sequencing data. In summary, IMPI enables a detailed analysis of the impact of UMI clustering and parameter setting changes on the measured allele frequencies. Conclusions: Regarding the BCR::ABL1 data, IMPI’s results underlined the need for caution while designing specialized single amplicon NGS approaches due to methodical limitations (e.g., high PCR-mediated recombination rate). This cannot be corrected using UMIs.

1382: Detection of Early Relapse by FDG-PET in the NPC Patients with Post-RT Detectable Plasma EBV DNA

1382: Detection of Early Relapse by FDG-PET in the NPC Patients with Post-RT Detectable Plasma EBV DNA

Clonal relapse dynamics in acute myeloid leukemia following allogeneic hematopoietic cell transplantation

AbstractPatients with acute myeloid leukemia (AML) who experience relapse following allogeneic hematopoietic cell transplantation (alloHCT) face unfavorable outcomes regardless of the chosen relapse treatment. Early detection of relapse at the molecular level by measurable residual disease (MRD) assessment enables timely intervention, which may prevent hematological recurrence of the disease. It remains unclear whether molecular MRD assessment can detect MRD before impending relapse and, if so, how long in advance. This study elucidates the molecular architecture and kinetics preceding AML relapse by using error-corrected next-generation sequencing (NGS) in 74 patients with AML relapsing after alloHCT, evaluating 140 samples from peripheral blood collected 0.6 to 14 months before relapse. At least 1 MRD marker became detectable in 10%, 38%, and 64% of patients at 6, 3, and 1 month before relapse, respectively. By translating these proportions into monitoring intervals, 38% of relapses would have been detected through MRD monitoring every 3 months, whereas 64% of relapses would have been detected with monthly intervals. The relapse kinetics after alloHCT are influenced by the functional class of mutations and their stability during molecular progression. Notably, mutations in epigenetic modifier genes exhibited a higher prevalence of MRD positivity and greater stability before relapse, whereas mutations in signaling genes demonstrated a shorter lead time to relapse. Both DTA (DNMT3A, TET2, and ASXL1) and non-DTA mutations displayed similar relapse kinetics during the follow-up period after alloHCT. Our study sets a framework for MRD monitoring after alloHCT by NGS, supporting monthly monitoring from peripheral blood using all variants that are known from diagnosis.

Cell-free human papillomavirus (HPV) DNA is a sensitive biomarker for prognosis and for early detection of relapse in locally advanced cervical cancer.

Human papillomavirus (HPV) is the cause of the majority of cervical cancers and has been showed to be released as cell-free tumour DNA (ctHPV DNA) into the circulation. We here analyse if ctHPV DNA could be used as a prognostic biomarker and/or to detect relapse earlier than traditional methods in locally advanced cervical cancer (LACC). 74 patients with LACC were included, 66/74 were positive for 13 high-risk HPV-types using a bead-based assay on tumour biopsies. HPV-type-specific droplet digital PCR (ddPCR) assays were developed. Longitudinal plasma samples were then analysed for the biopsy-verified HPV-type for each patient. 418 plasma samples were analysed. Patients were followed for a median of 37 months. Results were correlated to tumour- and clinical characteristics. 92.4% of pre-treatment plasma samples were positive for ctHPV DNA. Persistent ctHPV DNA in end-of-treatment, early follow-up (1-2 months after end-of-treatment) or tumour evaluation (3-4 months after end-of-treatment) plasma was correlated with worse progression-free survival (p < 0.001) compared to if ctHPV DNA was not found. The positive predictive value of ctHPV-status at early follow-up for predicting disease progression was 87.5% and the negative predictive value was 89.3%. ctHPV DNA was found in plasma before relapse was diagnosed on radiology in all patients (n=10) who experienced relapse after complete clinical response to treatment with a median 315 days lead time. ctHPV DNA in follow-up plasma is a promising prognostic biomarker in patients with LACC, useful for analysis of response to therapy and for early detection of relapse.

Acalabrutinib, venetoclax, and obinutuzumab in relapsed/refractory CLL: final efficacy and ctDNA analysis of the CLL2-BAAG trial

AbstractThe phase 2 CLL2-BAAG trial tested the measurable residual disease (MRD)–guided triple combination of acalabrutinib, venetoclax, and obinutuzumab after optional bendamustine debulking in 45 patients with relapsed/refractory chronic lymphocytic leukemia (CLL). MRD was measured by flow cytometry (FCM; undetectable MRD <10–4) in peripheral blood (PB) and circulating tumor DNA (ctDNA) using digital droplet polymerase chain reaction of variable-diversity-joining (VDJ) rearrangements and CLL-related mutations in plasma. The median number of previous treatments was 1 (range, 1-4); 18 patients (40%) had received a Bruton tyrosine kinase inhibitor (BTKi) and/or venetoclax before inclusion, 14 of 44 (31.8%) had TP53 aberrations, and 34 (75.6%) had unmutated immunoglobulin heavy-chain variable region genes. With a median observation time of 36.3 months and all patients off-treatment for a median of 21.9 months, uMRD <10–4 in PB was achieved in 42 of the 45 patients (93.3%) at any time point, including 17 of 18 (94.4%) previously exposed to venetoclax/BTKi and 13 of 14 (92.9%) with TP53 aberrations. The estimated 3-year progression-free and overall survival rates were 85.0% and 93.8%, respectively. Overall, 585 paired FCM/ctDNA samples were analyzed and 18 MRD recurrences (5 with and 13 without clinical progression) occurred after the end of treatment. Twelve samples were first detected by ctDNA, 3 by FCM, and 3 synchronously. In conclusion, time-limited MRD-guided acalabrutinib, venetoclax, and obinutuzumab achieved deep remissions in almost all patients with relapsed/refractory CLL. The addition of ctDNA-based analyses to FCM MRD assessment seems to improve early detection of relapses. This trial was registered at www.clinicaltrials.gov as #NCT03787264.