Comparison of Clinico-Radiological Features between Congenital Cystic Neuroblastoma and Neonatal Adrenal Hemorrhagic Pseudocyst

OBJECTIVE: To evaluate the radiological and clinical findings of congenital cystic neuroblastomas as compared with those of the cystic presentation of neonatal adrenal hemorrhage. MATERIALS AND METHODS: We analyzed the US (n = 52), CT (n = 24), and MR (n = 4) images as well as the medical records of 28 patients harboring congenital cystic neuroblastomas (n = 16) and neonatal adrenal hemorrhagic pseudocysts (n = 14). The history of prenatal detection, location, size, presence of outer wall enhancement, internal septations, solid portion, calcification, turbidity, vascular flow on a Doppler examination, and evolution patterns were compared in two groups of cystic lesions, by Fischer's exact test. RESULTS: All (100%) neuroblastomas and three (21%) of the 14 hemorrhagic pseudocysts were detected prenatally. Both groups of cystic lesions occurred more frequently on the right side; 11 of 16 (69%) for neuroblastomas and 11 of 14 (79%) for hemorrhagic pseudocysts. The size, presence of solid portion, septum, enhancement, and turbidity did not differ significantly (p > 0.05) between the two groups of cystic lesions. However, tiny calcifications (n = 3) and vascular flow on color Doppler US (n = 3) were noted in only neuroblastomas. The cystic neuroblastomas became complex solid and cystic masses, and did not disappear for up to 90 days in the three following cases, whereas 11 of the 14 (79%) hemorrhagic pseudocysts disappeared completely and the three remaining (27%) evolved to calcifications only. CONCLUSION: Although the imaging findings of two groups of cystic lesions were similar, prenatal detection, the presence of calcification on initial images, vascularity on color Doppler US, and evolution to a more complex mass may all favor neuroblastomas.