[Neonatal hyperinsulinism, congenital corporeal hemihypertrophy, tumor of the breast in adolescence].

The authors report the association of neonatal hyperinsulinism (nesidioblastosis) and congenital hemihypertrophy in an infant. At the age of 13 6/12 years fibro-adenomas of the breast occurred. The diagnosis of Beckwith-Wiedemann syndrome is discussed.