RESUMO
A case of aggressive adult neuroblastoma mimicking acute leukemia with fulminant course and fatal outcome is described. Pancytopenia and circulating blasts cells at presentation suggested the diagnosis of acute leukemia in the previously healthy 38 years old Caucasian male patient, but flow-cytometry analysis of the bone marrow disclosed the correct diagnosis of neuroblastoma. The immunophenotype was CD45-/CD56+/CD9+ in around 50% of the mononuclear cells, indicating neuroectodermal origin of the malignant cells. Subsequently, the diagnosis was confirmed by immunohistochemical staining of a bone marrow biopsy. A review of the reported cases of neuroblastoma with leukemic features showed that several of them were misdiagnosed as having leukemia and that the diagnosis of neuroblastoma was made at autopsy examination, indicating that misdiagnosis may happen more often than is appreciated. It is in our opinion that the diagnosis of neuroblastoma should be considered in all cases of acute leukemia and pancytopenia, regardless of the age group of the patients.