Acute Lymphoblastic Leukemia ALL
Conditions
Keywords
Pediatric acute lymphoblastic leukemia, Minimal residual disease, Cell-free DNA, Liquid biopsy, Fragmentomics, Methylome, Clonal evolution
Brief summary
Minimal residual disease (MRD) monitoring is a key prognostic factor in pediatric acute lymphoblastic leukemia (ALL). Currently, MRD assessment relies mainly on cellular DNA obtained from bone marrow aspirates. Although highly informative, this approach has limitations, including the need for invasive procedures and the fact that it reflects only the bone marrow compartment. Tumor cells release fragments of genomic DNA into the bloodstream, known as circulating cell-free DNA (cfDNA). In solid tumors, cfDNA analysis has emerged as a valuable non-invasive biomarker for disease monitoring and treatment response. Recent studies have shown that cfDNA is detectable in pediatric ALL. This study aims to investigate whether plasma cfDNA analysis could represent an alternative or complementary approach to bone marrow-based MRD assessment. cfDNA may better reflect the global tumor burden across the entire body and allow more frequent longitudinal monitoring during treatment. The primary objective is to assess the correlation between MRD measured in plasma cfDNA and MRD measured in bone marrow cellular DNA at two key timepoints of treatment: the end of induction (Day 29) and the end of consolidation (Day 71-78). Secondary objectives include evaluating the correlation between peripheral blood cellular DNA and bone marrow MRD, describing clonal evolution using cfDNA throughout treatment and follow-up, exploring the concordance of genomic alterations detected in cfDNA and other biological compartments, assessing the prognostic value of cfDNA MRD for relapse risk and event-free survival, and characterizing cfDNA fragmentome and methylome signatures in patients compared with healthy controls. The study will include children and adolescents with newly diagnosed ALL treated at two AP-HP pediatric hematology centers, as well as a control cohort of healthy children undergoing HLA typing for sibling stem cell transplant.
Interventions
OTHERBiological sample collection
Additional peripheral blood samples will be collected during treatment and follow-up for cell-free DNA analysis. Residual samples from bone marrow and cerebrospinal fluid collected as part of standard clinical care will also be analyzed.
Sponsors
Assistance Publique - Hôpitaux de Paris
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
No minimum to 18 Years
Healthy volunteers
Yes
Inclusion criteria
ALL population * Age \< 18 years * Newly diagnosed B-cell or T-cell acute lymphoblastic leukemia * Absence of BCR::ABL1 rearrangement * For infants (\<12 months), absence of KMT2A rearrangement * Inclusion before initiation of corticosteroid therapy or chemotherapy * Written informed consent from legal guardians * Affiliation to a national health insurance system Control population * Age \< 18 years * Undergoing blood sampling for HLA typing in the context of bone marrow donor evaluation * Sibling of a patient with leukemia * Written informed consent from legal guardians * Affiliation to a national health insurance system
Exclusion criteria
* Pregnant or breastfeeding patients * Patients not affiliated with a health insurance system
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Correlation between plasma cfDNA MRD and bone marrow MRD | Up to day 78 (end of consolidation) | Pearson correlation coefficient between minimal residual disease (MRD) measured in plasma circulating cell-free DNA and MRD measured in bone marrow cellular DNA. Analyses will be performed according to the type of molecular target used for MRD detection (IG/TCR rearrangements, genomic breakpoints, or pathogenic variants). End of induction (Day 29) and end of consolidation (Day 71-78) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Correlation between peripheral blood cellular DNA MRD and bone marrow MRD | At day 29 | Pearson correlation coefficient between MRD measured in peripheral blood cellular DNA and MRD measured in bone marrow cellular DNA. |
| Clonal evolution detected in cell-free DNA | At day 1 | Mutation profiles of cfDNA across multiple timepoints during treatment and follow-up |
| Concordance of genomic alterations between cfDNA and other biological compartments | At diagnosis | Qualitative and quantitative comparison of genomic alterations detected at diagnosis in cfDNA and in other sample types (bone marrow, cerebrospinal fluid, and other tissues if available) |
| Prognostic value of cfDNA MRD | Up to 5 years of follow-up | Association between cfDNA MRD levels and relapse-free survival and event-free survival |
| Fragmentome and methylome profiles of circulating DNA | Up to 5 years | Characterization and comparison of cfDNA fragment size patterns and methylation signatures between patients and healthy controls at diagnosis and during treatment. At baseline and during treatment |
Countries
France
Contacts
CONTACTMarion Strullu, MD PhD
CONTACTJérôme Lambert, MD PhD
Outcome results
None listed