From standardization to precision medicine: Evolution of European Leukemianet recommendations in Philadelphia-negative myeloproliferative neoplasms

The European LeukemiaNet (ELN) recommendations have been instrumental in shaping the diagnosis, risk stratification, and management of Philadelphia-negative myeloproliferative neoplasms (MPNs), including polycythemia vera, essential thrombocythemia, and primary myelofibrosis. Over the past two decades, these recommendations have evolved from consensus-based frameworks focused on response standardization to increasingly sophisticated, evidence-based and biologically informed approaches. Early efforts primarily aimed to harmonize response criteria across clinical studies, establishing a foundation for consistent therapeutic evaluation. Subsequent updates introduced risk-adapted treatment strategies centered on thrombotic risk, reflecting the major determinants of morbidity and mortality in these disorders. However, the limitations of surrogate endpoints prompted a shift toward clinically meaningful outcomes, including symptom burden, vascular events, and disease progression. More recent advances have been driven by the integration of molecular genetics and the adoption of structured evidence-based methodologies, enabling refined diagnostic classification and more accurate prognostic assessment. Contemporary ELN frameworks increasingly incorporate dynamic clinical parameters, genomic profiling, and emerging biomarkers, supporting a transition toward individualized, risk-adapted therapeutic strategies. Beyond their role in standardizing MPN management, ELN recommendations have also influenced clinical trial design, endpoint selection, risk stratification, and therapeutic decision-making. Evidence from prospective studies and real-world cohorts supports the clinical applicability of these frameworks, although their implementation remains heterogeneous across healthcare settings. This review provides a comprehensive and critical overview of the evolution and implementation of ELN recommendations, highlighting their impact on clinical research and routine practice, current limitations, and future directions toward precision medicine in Philadelphia-negative MPNs.