Neuroblastoma in the neonate.

Neuroblastoma is the most common malignant neoplasm occurring in the neonate and arguably the most variable in its presentation. This review examines differences in the tumor's clinical course in the context of known biologic determinants of behavior. Tumors that would go undetected except for prenatal ultrasonography or postnatal neuroblastoma screening characteristically undergo spontaneous regression or maturation and require little or no treatment. Most low stage tumors with favorable biological features are effectively treated with surgery alone. The more bulky locoregional (stage 3) tumors require chemotherapy in addition to surgery. The most challenging tumors are those that are disseminated at birth (stages 4 and 4S). Management plans for these tumors are based on the biological characteristics of the tumor and (in the case of stage 4S tumors) on the presence and extent of functional embarrassment of vital organs.