AbstractObjectivesThe incidence of congenital neuroblastoma has increased in the recent years. The purpose of this study was to describe the clinical and biochemical characteristics of cases of congenital neuroblastoma diagnosed in our center.Case presentationWe report three cases of congenital neuroblastoma diagnosed in our hospital. In two, diagnosis was made prenatally, whereas the other case was detected in the immediate neonatal period. In the three cases, neuroblastoma was located in the abdominal region and exhibited elevated concentrations of catecholamines or their metabolites in single voided urine samples. Two tumors were classified as stage M, and one as stage L2. TheN-MYConcogen was not amplified in any of the cases studied. Histopathological analysis was favorable in the three cases. The tumor was resected in two patients. The three received chemotherapy.ConclusionsThe measurement of catecholamines and their metabolites is essential in the diagnosis of neuroblastoma. When 24 h urine cannot be collected, single voided urine can be used to calculate the index based on creatinine concentrations.