Introduction Treating acute myeloid leukemia (AML), a diverse group of hematological cancers affecting bone marrow and blood, remains difficult, with a five-year survival rate of about 30%. Although screening for genetic mutations and fusion genes has become essential in AML diagnosis and risk stratification, the clinical significance of copy number aberrations (CNAs) remains poorly understood. To this end, we conducted a multicenter prospective clinical trial (ChiCTR2300077695) to characterize the genomic landscape of CNAs using shallow whole-genome sequencing (sWGS), termed LeukoPrint, in AML. Interim results from the first 205 patients (pts) are reported here.

Methods In this prospective multicenter clinical trial, we aim to enroll 600 newly diagnosed AML pts (excluding APL) across 13 participating hospitals in China. Bone marrow samples were collected and underwent CNA profiling via LeukoPrint (1× sWGS) at three stages: pretreatment, post-induction, and relapse. CNAs only those greater than 5 Mbp were analyzed. Conventional karyotyping analysis was performed in parallel for this cohort, and its diagnostic performance was compared with LeukoPrint. European Leukemia Net (ELN)-defined CNAs were used for risk stratification, consistent with standard cytogenetic analysis protocols. The trial received approval from the Ethics Committees of all participating hospitals, and all pts provided informed consent. By April 9, 2025, 205 pts were enrolled in this study, with 136 in the younger group (aged 18–59) and 69 in the older group (aged ≥60). All pts underwent CNA profiling using LeukoPrint at least twice, at pretreatment and post-induction phases.

Results Using LeukoPrint, we detected 193 CNAs in 87 pts (42.4% of the cohort). No notable difference in detection rates was observed between younger and older groups (41.9% vs. 43.5%). CNAs were frequently identified in chromosomes 7, 8, 11, and Y (each with >5% prevalence), with the most common recurrent CNAs occurring at 8q24.21 (13% prevalence), the locus containing the MYC oncogene. Recurrent deletions were predominantly observed in 5q31.3 and 7q36.1, the genomic regions harboring the oncogenes ACSL6, CD74, and EZH2. LeukoPrint outperformed karyotyping in CNA detection (42.4% vs. 27.3%), enhancing results for 51 pts (24.9% of the cohort). Notably, 38 pts, initially classified with normal karyotypes or failed karyotyping, were reclassified as carrying CNAs. Applying the 2022 ELN criteria, three pts initially classified as low- or intermediate-risk based on genetic mutations, fusions, and karyotypes were reclassified as high-risk following LeukoPrint analysis in place of karyotyping. Clinical follow-up in two cases confirmed poor outcomes in one, supporting LeukoPrint's prognostic value.

LeukoPrint demonstrates strong potential for prognostic prediction by monitoring dynamic change of molecular response in 115 pts. A significantly higher proportion of pts with post-induction CNAs were identified as non-responders than those without CNAs (6 vs. 3). Similarly, the proportion of pts without detectable post-induction CNAs was 95.5% in complete remission (CR, n=22), 83.3% in CR with partial hematologic recovery (CRh, n=6), 71.4% in CR with incomplete hematologic recovery (CRi, n=7), 0% in partial remission (PR, n=3), and 0% in non-responders (NR, n=3).

Copy-neutral loss of heterozygosity (CN-LOH) occurs when one allele is lost and the remaining allele is duplicated, resulting in no net change in copy number. This genomic alteration, such as TP53 CN-LOH, can have significant clinical impact but is undetectable by traditional karyotyping or fluorescence in situ hybridization (FISH). LeukoPrint identified CN-LOH in 43 (20.9%) of 205 pts in this cohort. Notably, CN-LOH was detected in 25 out of 114 pts without detectable CNAs, revealing that LeukoPrint provides additional insights into chromosomal aberrations in 12% (25/205) of pts. Combined with 24.9% from standard LeukoPrint analysis, LeukoPrint enhanced CNA detection in at least 36.9% of pts.

Conclusions LeukoPrint outperforms traditional karyotyping in detecting CNAs, improving data accuracy in over one-third of pts in this cohort. It enables dynamic monitoring of treatment response and disease progression, demonstrating strong correlation with clinical outcomes. These findings suggest that LeukoPrint holds significant promise as a complementary or alternative tool for conventional cytogenetic methods in AML.

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2025
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