Solitary osteochondroma: spontaneous regression.

Osteochondromas are the most common benign bone tumours. Nevertheless, their origin and biological behaviour are poorly understood. Rarely, spontaneous regression of osteochondromas may occur. We report the case of a 9-year-old girl with a solitary osteochondroma of the femur that regressed almost completely within 4 years, a fact that should be taken into account when deciding the management of these lesions, especially in young children.