Prepubertal gynecomastia caused by an adrenal tumor. Diagnostic value of ultrasonography.

Prepubertal gynecomastia is a rare disorder that may be associated with adrenal or testicular tumors. An adrenal tumor causing a mixed feminizing-virilizing syndrome in a 6-year-old boy was identified by ultrasonography, whereas excretory urography failed to show any abnormality. Highly elevated estrone concentrations were found in the plasma, as were more modestly increased levels of estradiol, testosterone, androstenedione, and 11-deoxycortisol. After removal of the tumor, all hormonal concentrations returned to normal prepubertal levels.