Skin hamartoma on the hand of a newborn infant.

Skin hamartoma is an extremely rare disease on the hand in newborn infants. Reported herein is the case of a newborn infant who presented with a skin hamartoma on the hand. The patient was a girl born at 37 weeks of gestational age. The mass was seen on her proximal left thumb at birth. The mass had a spherical diameter of 4 cm and was pedunculated. One the day after birth, the stalk on the mass was ligated in the neonatal intensive care unit. The mass was diagnosed as skin hamartoma on histopathology. At 1 year of age, the child had good hand function, and no recurrence of the neoplasia was evident.