Benign bone tumours. Coloured X-ray of multiple tumours in a patient's left hand. These are chondromas, benign (non-cancerous) tumours that arise from cartilage tissue. They are most common in adolescents and young adults. Chondromas rarely cause symptoms, but may weaken bones making them more prone to fracturing. Treatment is with surgical removal of the tumours. This hand is missing the index finger, perhaps due to amputation to remove a problematic tumour.