Neurologic complications of acute myeloid leukemia. Diagnostic approach and therapeutic modalities.

Acute myeloid leukemia (AML) comprises a heterogeneous group of aggressive blood malignancies that arise from clonal expansion of malignant hematopoietic precursor cells in the bone marrow. Neurologic manifestations of these malignancies are manifolds. AML is the most common form of acute leukemia in adults and this review describes the neurologic complications in this age group. Neurologic symptoms and signs may develop in AML either from a direct neoplastic involvement of the central or the peripheral nervous system or as an indirect effect of the disease process. Direct involvement of the nervous system includes invasion of the central or the peripheral nervous system (parenchymal and leptomeningeal dissemination, myeloid sarcoma, neuroleukemiosis). Thrombotic and hemorrhagic events are common manifestations of indirect involvement of the nervous system and they are the outcome of hyperleukocytosis, thrombocytopenia and coagulopathy. Many neurologic complications are iatrogenic and include diverse categories such as lumbar puncture and intrathecal or systemic chemotherapy and targeted therapies, radiotherapy and allogeneic stem cell transplantation. Most neurologic manifestations require urgent treatment and confer a poor prognosis. This review describes the neurologic complications of acute myeloid malignancies in the era of contemporary treatment. Those manifestations require expert consideration of their origin as they are being identified with increasing frequency as patients survive longer.