Abstract
Introduction: Atypical chronic myeloid leukemia (aCML), BCR-ABL1 negative is a rare myelodysplastic syndromes (MDS)/myeloproliferative neoplasm (MPN) for which no current standard of care exists. We present one of the rare presentations of aCML in an elderly patient.
Case: A 76 year old male presented to the Hematology clinic for consultation after discharge from local hospital for elevated WBC count. Past medical history was significant for COPD, acid reflux, peripheral arterial disease and hypertension. Physical exam was unremarkable. Initial labs were significant for leukocytosis of 30 k/cu mm, anemia with Hb 10 gm/dl, thrombocytosis 695,000 with neutrophilia of ANC 25,200. Peripheral blood was negative for JAK2 V617F and BCR-ABL. Peripheral blood flow cytometry showed granulocytic left shift with 1.5% myeloblasts. Bone marrow biopsy suggestive of hypercellular marrow (100%) with myeloid predominance, atypical megakaryocytes, increased ring sideroblasts (49% of NRBC), increased blasts (5%) and dysgranulopoeisis over all suggestive of Myelodyplastic Syndrome/Chronic Myeloproliferative Disorder (MDS/MPD). Cytogenetics were positive for U2AF1 positive, CSF3R T6181, CSF3R Q776 pathognomonicof atypical CML and negative for BCR-ABL, FLT3. He was considered transplant ineligible. He was started on Azacitadine and is currently receiving 2nd cycle therapy. He is also receiving darbepoeitin periodically to avoid frequent transfusions. He is currently transfusion independent.
Discussion: Increased WBC count (e.g., cutoffs of >40×109/L or 50×109/L), increased percentage of peripheral blood myeloid precursors, female sex, and older age are adverse prognostic factors for overall survival or leukemia-free survival in aCML. aCML cases lack in Philadelphia chromosome. Overall 50-65% of patients show cytogenetic abnormalities. The most frequent is +8 (25%). Other changes such as -7 and del(12p) have also been recurrently observed. Patients with aCML have an estimated median survival between 14 and 30 months. aCML tends to exhibit a more aggressive clinical course than other MDS/MPN subtypes.
No relevant conflicts of interest to declare.
