Fourteen children with adrenal cortical carcinoma were evaluated by ultrasonography. The neoplasms, 2.5 cm-19 cm in maximum diameter, were all well circumscribed. The four smaller lesions were either homogeneously hypoechoic (2 patients) or generally hyperechoic (2 patients). In the 10 patients with larger tumors, a complex predominantly echogenic pattern was demonstrated, eight of which contained radiating linear echoes, the "scar sign". This finding, although not specific, when present in a large adrenal mass, is suggestive of a cortical carcinoma. Associated findings of vascular invasion or retroperitoneal adenopathy supported the diagnosis of a malignant adrenal neoplasm in 3 patients. © 1990 Springer-Verlag.203163165