Abstract
We present one case of a chest wall hamartoma diagnosed in a 4-week-old boy. This entity is an extremely rare but characteristic congenital malformation of the ribs in infancy. To avoid maltreatment, it has to be distinguished from benign and malignant neoplasms on the basis of distinct histological features presented here. The immunohistochemical localization of various collagen types supports the notion of the hamartomatous nature of this lesion.