Targeted molecular characterization shows differences between primary and secondary myelofibrosis

Area of Science:

• Hematology
• Oncology
• Molecular Biology

Background:

• Myelofibrosis (MF), a BCR-ABL1-negative myeloproliferative neoplasm, presents as primary (PMF) or secondary (SMF) to other MPNs.
• MF is associated with a high risk of transformation to acute myeloid leukemia (AML) and reduced life expectancy.

Purpose of the Study:

• To investigate the molecular landscape differences between PMF and SMF using targeted next-generation sequencing.
• To compare the prognostic impact of identified molecular alterations in PMF and SMF.

Main Methods:

• Targeted next-generation sequencing was employed to analyze genetic mutations in 86 PMF and 59 SMF patients.
• The study compared mutation frequencies and correlated them with survival outcomes and established risk stratification systems (DIPSS, MYSEC-PM).

Main Results:

• PMF exhibited higher frequencies of ASXL1 and SRSF2 mutations compared to SMF.
• Poorer survival in PMF was linked to RNA splicing (SRSF2) and TP53 mutations, while in SMF, ASXL1 and TP53 mutations indicated worse prognosis.
• Specific mutation patterns (TP53/SRSF2 in PMF, TP53/ASXL1 in SMF) correlated with increased risk scores and improved patient stratification, particularly in intermediate-risk groups.

Conclusions:

• PMF and SMF possess distinct, though not entirely specific, molecular profiles that influence prognosis.
• Differences in disease history may contribute to observed molecular and prognostic variations.
• Integrating molecular mutation data with existing clinical risk scores offers a more refined approach to assessing myelofibrosis prognosis.