[Sequential development of BCR::ABL1-positive chronic myeloid leukemia during treatment of JAK2 V617F-positive essential thrombocythemia].

Source: PubMed, NCBI / U.S. National Library of Medicine

[Rinsho ketsueki] The Japanese journal of clinical hematologyGoto Midori, Higashi Takehiro, Morimoto Hiroaki, et al.Published 1/1/2026Last synced 5/29/2026Status: syncedPMID: 42128863DOI: 10.11406/rinketsu.67.328

We report a rare case of JAK2 V617F-positive essential thrombocythemia (ET) followed by BCR::ABL1-positive chronic myeloid leukemia (CML) in a 47-year-old woman. Dasatinib induced deep molecular remission; however, persistent thrombocytosis required hydroxyurea. The persistence of the JAK2 V617F mutation despite BCR::ABL1 suppression suggests distinct clonal populations. This case underscores the importance of vigilance for secondary myeloproliferative neoplasms (MPNs) and clonal evolution when a new hematologic phenotype emerges in a patient with an established MPN. The coexistence of JAK2 V617F and BCR::ABL1 mutations is exceedingly rare and presents significant diagnostic and therapeutic challenges.

Educational only

This information is for general education and is not medical advice. Always talk to a licensed U.S. clinician about your situation, medications, or treatment decisions.