Whole-genome sequencing as an alternative to analyze copy number abnormalities in AML, MDS and MM.

e19023 Background: Genomic alternations especially copy number aberrations (CNAs) are particularly imperative for diagnostic classification and risk stratification in patients with acute myeloid leukemia (AML), myelodysplastic syndromes (MDS) and multiple myeloma (MM). With the technological advances of next generation sequencing (NGS), the current CCA test and the molecular tests are likely to be challenged by whole-genome sequencing (WGS), which is a more unbiased method to detect all types of genomic aberrations. Methods: 178 patients who met the clinical manifestations of blood malignancies were included in the study, including 89 patients with AML, 48 with MDS and 41 with MM. Bone marrow was collected and mononuclear cells were separated to harvest genomic DNA which was sequenced without capture at approximately 1x coverage depth (shallow whole-genome sequencing, sWGS). Genome-wide CNAs greater than 5 Mbp was analyzed for each sample. European Leukemia Net (ELN), Revised International Prognostic Scoring System (IPSS-R) or Revised International Staging System (R-ISS)-defining CNAs were selected and used to assign patients to a genetic risk group through the same classification systems that are used for CCA. Results: In this study, CNA events were identified in 109 (73.6%) patients via sWGS. By calculating frequencies of recurrent gains and losses at chromosome arm level, some recurrent events were detected like gains of chr 8 (observed in 12 AML and 9 MDS patients), chr 1 (observed in 18 MM patients), losses of chr 7 (observed in 9 AML and 3 MDS patients) and chr 13 (observed in 16 MM patients), which were consistent with previously reported cytogenetic events. Besides, amplifications of odd-numbered chromosomes were detected in 15(36.6%) of patients with multiple myeloma, including chromosomes 3, 5, 7, 9, 11, 15, 19 and/or 21. And the trisomy of chr 5, 7 or 9 are mainly observed with a frequency of 66.7%. Among 145 patients with CCA results, a high concordance of 97.7% (98.5%, 97.6% and 97.1% in AML, MDS and MM respectively) was achieved in CNA profiles at individual patient level with cytogenetics and/or FISH. Noteworthily, CNA events were detected in 20 of 28 (71.4%) MM patients with negative karyotyping results. Moreover, sWGS improved the overall diagnostic yield by reassign 18 patients (9 with AML and 9 with MDS) to risk categories with poorer prognosis. Nearly identical CNA profiles from the paired plasma and bone marrow suggest that peripheral blood may serve as a substitute to spare bone marrow aspiration. Conclusions: In summary, a streamlined sWGS provides an accurate, convenient and cost-effective approach to describe genomic profiles of CNAs in patients with AML, MDS and MM. Clinical trial information: ChiCTR2100052276.