Monocytosis is an adverse prognostic factor for survival in younger patients with primary myelofibrosis

Area of Science:

• Hematology
• Oncology
• Internal Medicine

Background:

• Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by bone marrow fibrosis.
• Accurate prognostic scoring systems are crucial for managing PMF and guiding treatment decisions.
• Previous systems, like the modified Dupriez prognostic scoring system (PSS), identified key risk factors but could be further refined.

Purpose of the Study:

• To evaluate the independent prognostic value of absolute monocyte count in patients with PMF.
• To develop an improved prognostic scoring system for PMF by incorporating monocyte count.
• To validate the new scoring system in an independent patient cohort.

Main Methods:

• Multivariable analysis was performed on a cohort of 129 PMF patients (median age, 52 years).
• The study assessed the predictive value of hemoglobin, leukocyte count, platelet count, and absolute monocyte count on survival.
• A new Mayo PSS was constructed by including monocyte count as a fourth risk factor and validated on a separate cohort of 97 PMF patients.

Main Results:

• An absolute monocyte count of >= 1 x 10(9)L(-1) was found to be an independent predictor of inferior survival in PMF (p=0.02).
• The new Mayo PSS, incorporating monocyte count, demonstrated significant discrimination between risk groups (p<0.0001).
• Median survival varied significantly across risk groups defined by the new PSS: 173 months (low-risk), 61 months (intermediate-risk), and 26 months (high-risk).

Conclusions:

• Absolute monocyte count is a significant independent prognostic factor in primary myelofibrosis.
• The addition of monocyte count to existing parameters creates a more accurate and validated prognostic scoring system for PMF.
• The improved Mayo PSS enhances risk stratification, potentially optimizing patient management and treatment strategies for PMF.