A first local study on 45 patients showed the prognostic impact of CALR mutation quantification in follow-up, independently of the European LeukemiaNet (ELN) prognostic score validated in this group of patients.~This study aims to evaluate a multicenter cohort of 260 patients, including all types of CALR-mutated MPNs and several follow-up samples, to model the temporal evolution of CALR allele burden.~Blood of MPN patients will be collected, at the time of diagnosis and for 3 years (max 1 sample/year), for the quantification of the CALR allele burden. During follow-up, a clinicobiological score to define the progression or not of the disease for each patient will be evaluated in Essential Thrombocythemia (ET) and MyeloFibrosis (MF).
Prospective study to evaluate the relevance of CALR allele burden monitoring as a molecular marker of disease progression.