PO62 | CLINICAL AND MOLECULAR DIAGNOSTIC CHALLENGES IN MYELOPROLIFERATIVE NEOPLASMS WITH LOW JAK2V617F ALLELIC BURDEN

Introduction. The detection of the JAK2V617F mutation plays a crucial role in diagnosing myeloproliferative neoplasms (MPNs). In clinical practice, a mutation with a VAF greater than 2% is definitively considered positive, a criterion also used to define Clonal Hematopoiesis of Indeterminate Potential (CHIP). In MPN field, according to WHO/ICC recommendations, highly sensitive methods should be employed to identify JAK2V617F when the variant allele frequency (VAF) is below 1%. Nevertheless, the assessment of a low JAK2V617F burden remains complex, as this mutation has been observed in individuals without hematological disorders, and no specific cut-off value has been established for MPN diagnosis. Aims. To investigate the clinical and molecular features of a patient cohort referred for suspected MPN with a JAK2V617F VAF of