Interest of CALR Allele Burden in Diagnosis and Follow-up of Patients With CALR Mutated Myeloproliferative Syndromes (CALRSUIVI)

For each disease, Hazard Ratio of the different trajectories of CALR allele burden to explain the time to onset of disease progression by the clinicobiological score.

Clinicobiological score : For ET, disease progression if ≥ 1 of: * leukocytosis \> 12 G/L or myelemia \> 10% or erythroblasts \> 1%, * anemia or thrombocytopenia not related to drug toxicity, * development or worsening of splenomegaly, * development of thrombocytosis (platelets \> 450 G/L) on cytoreductive therapy, * poor disease control (at least one change in therapy for reasons other than adverse events), * hematologic transformation or death related to hematologic pathology. For MF, disease progression if ≥ 1 of: * anemia \< 100 g/L, neutropenia \< 1 G/L, thrombocytopenia \< 100 G/L and/or development of general signs not previously present or recurring after improvement, * increase in leukocytosis \> 25 G/L not previously present, * appearance or aggravation of transfusion dependence, * appearance (\> 5 cm) or aggravation (\> 50%) of splenomegaly, * leukemic transformation or death related to the hematologic pathology.

Time frame: 3 years follow-up