Bilateral cystic neuroblastoma: imaging features and differential diagnoses.

Neuroblastoma is one of the most common malignant tumors of childhood, with 40 % arising in the adrenal glands. Bilateral adrenal involvement from synchronous development or metastatic spread of the tumor is seen in less than 10 % of children with neuroblastoma [1]. Neuroblastoma rarely presents as a cystic suprarenal mass that is difficult to differentiate from adrenal hemorrhage, extralobar sequestration, or dilated upper-pole renal calyces. To our knowledge, bilateral cystic neuroblastoma has not been previously reported. We present a case of bilateral cystic adrenal neuroblastoma to demonstrate the imaging features of this unusual entity, and to expand the differential diagnosis of bilateral cystic suprarenal masses in an infant.