Hematologic and molecular spontaneous remission following sepsis in acute monoblastic leukemia with translocation (9;11): a case report and review of the literature

Spontaneous remission in patients with acute myeloid leukemia (AML) is a rarely reported phenomenon of usually short duration. The etiology remains unclear, but an association with preceding blood transfusions or bacterial infections has been reported. Triggered immune responses are suggested to play a potential role in the development of spontaneous remission. Acute monocytic leukemia was diagnosed in a 61-yr-old male patient. Cytogenetic analysis revealed a sole translocation (9;11) (q22;q23) and RT-PCR the MLL/AF9 fusion gene. As a result of the patient's reduced performance status and septic condition, cytostatic therapy was withheld. No microorganisms could be detected. Hematologic and molecular remission occurred after initiating antibiotic therapy without any cytostatic treatment; 29 months after the initial diagnosis, he is in complete remission, and excellent physical condition. Our report includes a review of the literature since 1985, reporting cases of patients with AML and spontaneous remission together with informative cytogenetics. Balanced translocations such as in core binding factor (CBF) leukemias appear somewhat overrepresented. We speculate that AML-specific T cells might be relevant for induction of spontaneous remission and need to be further investigated.