Review Childhood adrenocortical tumours

Childhood adrenocortical tumours (ACT) constitute only about 0.2% ofall paediatric malignancies. However, the incidence of ACT varies across geographic regions and is remarkably high in southern Brazil. At presentation, most children show signs and symptoms ofvirilisation, which may be accompanied by manif estations ofthe hypersecretion ofother adrenal cortical hormones. Fewer than 10% ofpatients with ACT show no endocrine syndrome at presentation; these are often older children and adolescents. ACT is commonly associated with constitutional genetic abnormalities, particularly mutations ofthe P53 gene. Histological fea- tures are used to classify the tumours as adenomas or carcinomas; however, the distinction between these two subtypes is often difficult. The extent ofdisease is best evaluated by computed tomography or magnetic resonance imaging; the role ofpositron- emission tomographic scans has not been defined. Cure ofACT requires complete tumour resection. The role ofchemotherapy or radiotherapy has not been established, although definitive responses to several anticancer drugs have been documented. Among patients who undergo complete tumour resection, favourable prognostic factors include age < 4 years, smaller tumour size, signs of virilisation alone at presentation, and adenomatous tumour histology. Some children with ACT show abnormalities ofgrowth and development at the time ofpresentation, but these usually resolve after surgery. # 2004 Elsevier Ltd. All rights reserved. 1. Epidemiology Carcinomas are generally rare in children and adoles- cents. In the United States, Surveillance Epidemiology and End Results (SEER) data from the National Cancer Institute show that only about 1.3% ofall childhood carcinomas and only about 0.2% ofall childhood mal- ignancies are adrenocortical tumours (ACT) (1). Unlike paediatric carcinomas in general, which show a pro- gressive increase in incidence with age, ACT has a peak incidence between ages 0 and 4 years. The frequency of ACT is 0.4 per million during the first 4 years oflif e, and it decreases to 0.1 per million during the subsequent 10 years. It then rises to 0.2 per million during the late teens and reaches another peak during the fourth decade