Neuroblastoma presenting as acute lymphoblastic leukemia but correctly diagnosed after orbital fine-needle aspiration biopsy.

A 3 1/2-year-old girl with a diagnosis of common acute lymphoblastic leukemia antigen (CALLA)-positive acute lymphoblastic leukemia was noted to be hypertensive and developed a tonic-clonic seizure. Computed tomography scan of the head revealed a right orbital mass. Orbital fine needle aspiration biopsy demonstrated rosette-like arrangements of cells with fibrillar cytoplasmic processes suggesting neuroblastoma. The tumor cells were antineuron-specific enolase positive. The cytologic findings suggested neuroblastoma, a diagnosis confirmed on subsequent work-up. The difficulty in distinguishing neuroblastoma from acute lymphoblastic leukemia in the pediatric patient is discussed in terms of clinical and cytologic features.