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Bone cancer is the fourth most common cancer in people under 25 years of age,1 and osteosarcoma is the most common type of bone cancer in this age group. Very little is known about the aetiology of osteo-sarcoma in humans; the only known aetiologic agent is radiation.2,3 Other factors suggested to be related to osteosarcoma include tall stature, previous bone trauma and viruses.3–9 One case-control study observed an association between osteosarcoma and short length at birth.9 Genetic factors have been identified in a small percentage of cases.6,10,11 Osteosarcomas are distributed throughout the entire skeleton, with the rapidly growing long bones of the extremities affected most often among young people.12 An increase in osteosarcoma incidence around pubert