Impact of central nervous system involvement in AML on outcomes after allo-transplant and utility of pre-transplant cerebro-spinal fluid assessment.

Objective The primary objective was to assess the effect of central nervous system involvement in acute myeloid leukemia (CNS-AML) on outcomes after allogeneic hematopoietic stem cell transplant (allo-HCT). The secondary objective was to assess the utility of pretransplant cerebrospinal fluid (CSF) assessment in AML. Methods We retrospectively analyzed survival outcomes in 338 adult AML patients (with and without CNS-AML) after allo-HCT. CNS involvement was defined as clinical, pathological, or radiological evidence of CNS involvement any time after diagnosis. Results The median follow-up in surviving patients was 23.7 months. Twenty-five patients (7.4%) had prior history of CNS disease, with normal CSF pretransplant. Three patients had CSF blasts detected for the first time at pretransplant evaluation (0.88%). The 2-year OS and RFS in groups with and without CNS involvement were not significantly different. Patients with CNS-AML had significantly higher 1-year cumulative incidence of relapse (29.7% vs 16.9%, P = .048). Age more than 65 years and absence of marrow remission at transplant were significant adverse factors for survival. Conclusion CNS-AML is not an independent risk factor for survival after allo-HCT, but can be associated with higher relapse rates. Pretransplant CSF assessment has low yield in detecting new CNS disease pretransplant in AML.