Central nervous system involvement in acute myeloid leukemia patients undergoing hematopoietic cell transplantation

Knowledge regarding the rate of central nervous system (CNS) involvement and risk factors for its development in acute myeloid leukemia (AML) patients undergoing allogeneic hematopoietic cell transplantation (HCT) are limited. In this study we retrospectively evaluated CNS involvement in 327 patients who underwent myeloablative HCT at our institute in which all patients have cerebrospinal fluid examined by morphology or flow cytometry before HCT. Twenty-two patients (7%) had CNS AML involvement at pre-HCT evaluation. Covariates associated with such involvement were higher WBC at diagnosis, prior CNS or other extramedullary disease, and evidence of systemic disease at pre-HCT evaluation. History of prior CNS disease and disease status at pre-HCT evaluation allowed stratification of patients into 3 risk groups: 35% (20 patients), 16% (51 patients), and 3% (256 patients) rates of pre-HCT CNS involvement. Treatment of pre-HCT CNS disease was uniformly successful regardless of whether cranial irradiation therapy was used. Perhaps as a result, presence of CNS pre-HCT had no independent influence on post-HCT outcome, which was primarily influenced by status of systemic disease at time of HCT.