Spontaneous Remission Of Acute Myeloid Leukemia With Nf1 Alteration
Bradley, T., Zuquello, R. A., Aguirre, L. E., Mackrides, N., Chapman, J., Cimmino, L., Thomassen, A., & Watts, J. (2020). Spontaneous remission of acute myeloid leukemia with NF1 alteration. Leukemia research reports, 13, 100204. https://doi.org/10.1016/j.lrr.2020.100204
View Original Source →Abstract
Acute myeloid leukemia (AML) is defined by the presence of ≥ 20% myeloblasts in the blood or bone marrow. Spontaneous remission (SR) of AML is a rare event, with few cases described in the literature. SR is generally associated with recovery from an infectious or immunologic process, and more recently possibly with clonal hematopoiesis. We review the literature and assess the trends associated with SR, and report a new case of a 58-year-old man with a morphologic diagnosis of AML associated with a severe gastrointestinal (GI) tract infection. The patient had an NF1 variant that was previously unreported in AML as the only clonal abnormality. After treatment of the infection, the increased blast population subsided with no leukemia-directed therapy, and the patient has remained in a continuous, spontaneous complete remission for > 2 years.
Case Details
Disease Location
Bone marrow
Personal Characteristics
58-year-old hispanic man. History of ankylosing spondylitis treated with methotrexate and infliximab
Clinical Characteristics
He presented with fever, abdominal pain, and hematochezia during a trip to central america. Blood work revealed anemia and 6% circulating blasts. Bone marrow biopsy demonstrated 40-50% blasts, left-shifted myelopoiesis, and trilineage dysplasia. His anemia worsened, and he required blood transfusions. Intravenous antibiotics were started. CT imaging showed acute colitis. Repeat bone marrow examination showed 25% blasts with background dysplasia. Findings were consistent with acute myeloid dysplasia
Remission Characteristics
Over the next 2 weeks, the patient's symptoms resolved and his blood counts normalized. He underwent a third bone marrow biopsy 4 weeks after the initial assessment which demonstrated a cellular bone marrow (50-70%), increased megakaryocytes, and mild dyserythropoiesis. Blasts comprised 1% of total cells. The only abnormality found on the third bone marrow biopsy was an nf1 mutation (c.4430+delt;splice-region) with variant allele frequency (vaf) 17% on an expanded ngs panel.
Treatment & Mechanisms
Proposed Remission Mechanisms
Atypical marrow stress response in the setting of isolated nf1 mutation.
Clinical Treatment
Blood transfusion, IV antibiotics, bone marrow biopsy
Non-Clinical Treatment
None reported