Intrarenal neuroblastoma diagnosed by fine-needle aspiration: a report of two cases.

Neuroblastoma is an infrequent tumor of childhood usually located at any site containing sympathetic neural tissue-retroperitoneum and adrenal gland being the most common locations, followed by thoracopulmonary region, mediastinum, head and neck, and pelvis. Two primary renal neuroblastomas were diagnosed in a 6-yr-old boy and a 7-mo-old boy by computed tomography (CT)-guided fine-needle aspiration (FNA) cytology. The smears contained numerous individually scattered small and round cells, with scanty cytoplasm, related to a fibrillary matrix. Scattered larger cells with slightly more cytoplasm were seen among the smaller ones. No tubular or glomeruloid differentiation was noted. Considering the age and cytomorphology, a diagnosis of intrarenal neuroblastoma was made in both cases. An intrarenal mass in a child may occasionally be a neuroblastoma. Our cases demonstrate the usefulness of CT-guided FNA in diagnosing intrarenal masses in children.