Accelerated and blast phase myeloproliferative neoplasms.

Area of Science:

• Hematology
• Oncology
• Internal Medicine

Background:

• Myeloproliferative neoplasms (MPN) carry a risk of transforming into blast phase (MPN-BP) or accelerated phase (MPN-AP).
• Primary myelofibrosis (PMF) presents the highest risk of blastic transformation (14.2%), followed by polycythemia vera (PV) (6.8%) and essential thrombocythemia (ET) (3.8%).
• A prognostic model for leukaemic transformation (LT) in PMF incorporates IDH1 mutation, circulating blasts ≥3%, SRSF2 mutation, age >70 years, ASXL1 mutation, and anemia severity.

Purpose of the Study:

• To review the diagnostic, prognostic, and therapeutic approaches for MPN in accelerated or blast phase (MPN-AP/BP).
• To outline strategies for managing patients with MPN-AP/BP, emphasizing the role of allogeneic stem cell transplantation.

Main Methods:

• Review of current diagnostic criteria for MPN-AP/BP.
• Analysis of prognostic factors for leukaemic transformation in PMF.
• Discussion of contemporary treatment modalities for MPN-AP/BP, including chemotherapy, hypomethylating agents, targeted therapies, and stem cell transplantation.

Main Results:

• MPN-BP/AP is defined by ≥20% or 10-19% blasts, respectively.
• Risk stratification models aid in predicting leukaemic transformation in PMF.
• Treatment aims for complete remission to facilitate allogeneic stem cell transplantation for long-term survival.

Conclusions:

• Effective management of MPN-AP/BP requires a comprehensive diagnostic and prognostic framework.
• Allogeneic stem cell transplantation remains the only curative option for eligible patients with MPN-AP/BP.
• Current therapeutic strategies involve induction chemotherapy, hypomethylating agents, and targeted therapies, often in combination.