Thoracic neuroblastoma of the neonate.

Five cases of neonatal thoracic neuroblastoma were either clinically asymptomatic or presented as uncharacteristic respiratory distress. Chest radiography demonstrated a spectrum of abnormalities varying from a lobulated, apical thoracic mass with or without evidence of expansion, to a spindle-shaped paraspinal soft tissue widening, or a homogeneously dense hemithorax. In the newborn a neoplasm in the posterior mediastinum most likely represents a neuroblastoma, either primary or metastatic. In a high percentage of cases the primary tumour as well as possible skeletal metastases have an increased uptake of radiopharmaceuticals. Therefore a bone scan should be the next step for evaluation of the neoplasm. Supplementary sonographic screening of the retroperitoneum and lesser pelvis is easily performed and may contribute significant information. Urography is hardly mandatory any longer. Metrizamide CT myelography, highly recommended in infants and children, may be omitted in the neonate with no neurologic deficit. Urinary excretion of catecholamine metabolites is usually elevated and must always be determined.