Critical Role of Molecular-Based Stratification in Low-Risk Myelodysplastic Syndrome with Direct Progression to Acute Myeloid Leukemia: A Case Report.

The genomic landscape of myelodysplastic syndromes/neoplasms (MDS), a heterogeneous group of myeloid malignancies defined by bone marrow cell dysplasia with ineffective hematopoiesis, includes somatic and, less frequently, germline mutations in hematopoietic stem and progenitor cells, along with chromosomal abnormalities. The latest World Health Organization 2022 classification of myeloid neoplasms, as well as stratification in lower-risk (LR) and higher-risk (HR) MDS using either the Revised International Prognostic Scoring System (IPSS-R) or the Molecular International Prognostic Scoring System (IPSS-M), guide prognostic assessment and risk-adjusted therapy. We report the case of an 81-year-old patient diagnosed with LR-MDS according to IPSS-R that exhibited direct progression to acute myeloid leukemia. The retrospective analysis of paired DNA samples from MDS and leukemic phases, obtained four months apart, using both targeted next-generation sequencing and single nucleotide polymorphism array, indicated swift alterations in the genomic profile, being suggested that the leukemic clone emerged from the clone harboring homozygous TET2 and heterozygous SRSF2 variants that acquired RUNX1, BCOR, BCORL1 likely pathogenic mutations and trisomy 13. By employing IPSS-M for prognostic evaluation at the MDS phase, the patient would have been assigned to the HR-MDS category with a possible benefit from hypomethylating agent therapy. Risk stratification is of pivotal importance in a patient-centered approach to MDS treatment being significantly improved by incorporating the molecular genetic findings.