Snapshot A 4-year-old girl is brought to the emergency room after her parents felt an abdominal mass during her bath. She complains of headaches. On physical exam, her eyes jerk around erratically. Her feet also twitch occasionally. The abdominal mass is irregular, firm, and clearly crosses the midline. An MRI of her head shows potential metastasis to the skull. Introduction Malignant tumor from cells of sympathetic nervous system login to view 2 more bullets Epidemiology < 4 years old Most common cancer in infancy Most common extracranial solid malignancy ETIOLOGY Pathogenesis login to view 2 more bullets Genetics login to view 1 more bullet Associated conditions login to view 3 more bullets Presentation Symptoms login to view 5 more bullets Physical exam login to view 3 more bullets Evaluation Biopsy login to view 7 more bullets Urine (breakdown products of dopamine) login to view 2 more bullets Imaging login to view 2 more bullets Differential Diagnosis Wilms' tumor Rhabdomyosarcoma Germ cell tumors Hepatoblastoma Treatment Surgical resection With or without chemotherapy Complications Metastases to bone and skin Permanent neurological sequelae from opsoclonus myoclonus syndrome Prognosis Younger patients with better prognosis