Systemic Inflammatory Index in Polycythemia Vera and Its Prognostic Implications.

Area of Science:

• Hematology
• Oncology
• Inflammation

Background:

• Polycythemia vera (PV) is a myeloproliferative neoplasm.
• The systemic inflammatory index (SII), derived from neutrophil, lymphocyte, and platelet counts, is a potential prognostic marker.
• Previous research suggests SII predicts thrombotic and mortality risks in the general population.

Purpose of the Study:

• To evaluate the clinical and prognostic associations of SII in polycythemia vera (PV) patients.
• To determine if SII can refine risk stratification in PV.
• To compare the prognostic performance of SII with other complete blood count (CBC) parameters.

Main Methods:

• Retrospective analysis of 279 PV patients from Croatian and Serbian hematologic centers.
• Calculation of SII using absolute neutrophil count (ANC), absolute lymphocyte count (ALC), and platelet count (ANCxALC/platelet count).
• Evaluation of associations between SII, time to thrombosis (TTT), and overall survival (OS).

Main Results:

• Higher SII was significantly associated with shorter TTT (p = 0.004), particularly arterial thrombotic events.
• Higher SII was significantly associated with shorter OS (p < 0.001).
• SII improved risk stratification for thrombosis and survival, especially in PV patients over 60 years old, outperforming other CBC indices.

Conclusions:

• The systemic inflammatory index (SII) is a significant prognostic factor for thrombosis and survival in polycythemia vera (PV).
• SII offers enhanced risk stratification for PV patients, complementing existing risk models.
• These findings support the use of SII for personalizing treatment strategies in PV.