The growing incidences of secondary malignancies in long-term survivors of 
childhood leukemia following allogeneic bone marrow transplantation (alloBMT) 
are increasingly being reported. Among the late complications of conventional 
myeloablative alloBMT, the occurrence of secondary malignant solid tumors is of 
major concern. Secondary malignant and benign brain tumors such as astrocytoma, 
meningioma and glioblastoma have been described in long-term survivors of 
conventional myeloablative alloBMT. Here we report a case of secondary 
anaplastic oligoastrocytoma that developed 7 years after matched unrelated 
alloBMT for relapsing childhood acute myeloid leukemia (AML) with CNS 
involvement. Although isolated CNS relapse of primary leukemia following alloBMT 
is not uncommon, it is important to identify and define potential risk factors 
that may lead to the development of secondary brain tumors in children who 
received high-dose chemotherapy and irradiation prior to alloBMT presenting with 
progressive neurological symptoms and to differentiate them from leukemia 
relapse with CNS involvement.