Case Report of Aggressive Atypical Chronic Myeloid Leukemia
Posted: Thursday, April 30, 2020
A noteworthy case of BCR-ABL1–negative atypical chronic myeloid leukemia (aCML), which ultimately did not respond to treatment, was described by Philipp Ernst, MD, of the Friedrich Schiller University Jena, Germany, and colleagues in a Letter to the Editor in the Annals of Hematology. The outcome may highlight HLA-matched hematopoietic blood stem cell transplantation (HSCT) as a method of early intervention for this rare aggressive myeloproliferative disorder.
A 19-year-old patient presented with hepatosplenomegaly, right-sided colitis, mild anemia, increased granulopoiesis, dysplasia in megakaryopoiesis, and myeloproliferative adipose tissue disappearance. The SF3B1 and NF1 genes were mutated, but BCR-ABL1 gene fusion was not detected. “Since leukocytosis with more than 10% granulocytic precursors, hypercellular bone marrow, and less than 20% blasts in peripheral blood and bone marrow were also detectable, the patient met the criteria for atypical CML,” the authors noted.
The patient was initially treated with hydroxyurea and underwent an emergency hemicolectomy due to a suspected perforation. He then began cytoreductive therapy with cytarabine, which led to a partial remission. Five months after diagnosis, he received allogeneic HSCT from an HLA-mismatched donor. Due to complications, the patient required reduced-toxicity conditioning with cytarabine, treosulfan, and fludarabine. Tests confirmed trisomy 8 in about 20% to 35% of interphases, and subsequently, immunosuppressive therapy was reduced. Six months after transplantation, hydroxyurea treatment was reinitiated due to cytogenetic and hematologic recurrences. They planned another HSCT, however, on day 409, the patient presented with displacing splenic growth and died shortly after.
The investigators recommended that BCR-ABL1–negative cases be HLA-matched for HSCT as early as possible to treat this aggressive disease. However, cytoreductive therapy is often initially required. Whether the mutations in the SF3B1 and NF1 genes contribute to a poor prognosis warranted further investigation.
Disclosure: The study authors reported no conflicts of interest.