[18F-fluorodeoxyglucose-positron emission tomography imaging before and after treatment of chronic-phase chronic myeloid leukemia with tyrosine kinase inhibitors].

A 64-year-old man presented with abnormal imaging results on 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET), showing moderately increased FDG-uptake in the entire bone marrow. Blood tests revealed leukocytosis, thrombocytosis, and increased lactate dehydrogenase levels. Furthermore, the neutrophil alkaline phosphatase score decreased. Bone marrow examination revealed marked hypercellularity of myeloid and megakaryocytic lineages without an excess of blasts. Cytogenetic analysis of the bone marrow demonstrated Philadelphia chromosome, and fluorescence in situ hybridization analysis was positive for BCR-ABL1 fusion genes. Thus, the patient was diagnosed with chronic myeloid leukemia (CML) in the chronic phase and tyrosine kinase inhibitor therapy with 100 mg of dasatinib daily was initiated. Complete cytogenetic response and a major molecular response were achieved at 3 and 12 months post-treatment, respectively. FDG-uptake values of the bone marrow remarkably decreased along with the remission status of the disease. FDG-PET images at pre- and post-treatment of CML are rarely compared, so we report this case as an important reference.