Outcomes and prognostic factors of hematopoietic stem cell transplantation in adult patients with acute myeloid leukemia and central nervous system involvement.

OBJECTIVE

Acute myeloid leukemia (AML) with central nervous system (CNS) involvement is rare and associated with a poor prognosis, but allogeneic hematopoietic stem cell transplantation (HSCT) offers the potential for a cure. However, comprehensive data on clinical characteristics, prognosis, and post-transplant CNS complications remain limited.

METHODS

We conducted a retrospective analysis of 64 CNS+AML patients who underwent allogeneic HSCT at Toranomon Hospital and Toranomon Hospital Kajigaya.

RESULTS

CNS involvement was limited to the cerebrospinal fluid in 64%, while 36% had intracranial mass lesions. All patients received intrathecal chemotherapy, and 40.6% underwent cranial irradiation. Refined Disease Risk Index (rDRI) was low-intermediate in 25% and high-very high in 75%, and 56.2% had active CNS disease at transplantation. The 2-year DFS rate was 34.8%, and the 2-year cumulative incidence of relapse (CIR) was 35.2%. High or very high rDRI and poor performance status were associated with inferior outcomes in the multivariate analysis. The CIR of CNS disease was 12.7%, with a trend toward higher rates (18.8%) observed in patients with high/very high rDRI. Post-transplant CNS complications included two cases of leukoencephalopathy within 1 month and two cases of radiation-induced brain necrosis approximately 19 months after transplantation.

CONCLUSIONS

Outcomes after HSCT for CNS+ AML are primarily determined by rDRI and performance status, underscoring the importance of systemic disease control.