Cytoreductive treatment in patients with CALR‐mutated essential thrombocythaemia: a study comparing indications and efficacy among genotypes from the Spanish Registry of Essential Thrombocythaemia

Results from an analysis of 1446 patients with essential thrombocythemia (ET) who received cytoreductive therapy showed that the duration of complete response (CR) for patients with CALR-mutated ET was significantly shorter than for the rest of the patient population (P =.003), including those with MPL-mutated, JAK2V617F-positive, and triple-negative disease. In low-risk patients, time from diagnosis to initiation of cytoreductive therapy was shorter in CALR positive disease than other genotypes. The median time to CR was also significantly longer for patients with CALR-mutated ET than with other genotypes (P <.0001).