AML/MDS transformation risk in MPN: Impact of attained age and disease duration

Results from a nationwide Swedish cohort study, evaluating the risk of transformation to acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) in patients with myeloproliferative neoplasms (MPN), were published in the European Journal of Haematology by Batyrbekova et al. Attained age and disease duration were analyzed as continuous variables in patients with primary myelofibrosis (PMF; n = 1,080), polycythemia vera (PV; n = 7,156), and essential thrombocythemia (ET; n = 6,810). Follow-up began 3 months after MPN diagnosis (index date) to evaluate transformation risk over time. 

Key data: In patients with PV and ET, both attained age and time since the index date were associated with AML transformation (p < 0.05), whereas only attained age was associated with MDS transformation (p < 0.05). In PMF, AML transformation rates were highest early after diagnosis and declined over time. For MDS transformation in PMF, only attained age was associated with increased risk (p < 0.05). Among patients aged 70 years at the index date, the estimated 10‑year cumulative incidence of AML transformation was 3.5% in PV, 4.7% in ET, and 18.2% in PMF; corresponding incidences of MDS were 1.7%, 3.1%, and 10.7%, respectively. 

Key learning: Transformation risk to AML and MDS varies across MPN subtypes and is influenced by both attained age and disease duration, supporting consideration of these factors in patient risk assessment.