Osteosarcoma in pre-adolescent patients.

The medical records of 38 pre-adolescent (aged < or = 10 years) and 43 adolescent (aged 11 - 15 years) patients with primary osteosarcoma treated using the same protocol were reviewed in order to determine whether the clinical features and prognosis differed between these two groups. Gender, tumour location, tumour size, serum levels of alkaline phosphatase and lactic dehydrogenase before treatment, and chemotherapy-induced tumour necrosis were recorded, together with survival data. These parameters were compared in the two groups, and their prognostic significance was evaluated in the pre-adolescent patients. There were no statistically significant differences in the clinical parameters between pre-adolescent and adolescent patients. Only a poor level of chemotherapy-induced tumour necrosis was significantly associated with a poor prognosis in pre-adolescent patients. This study indicates that osteosarcoma behaviour is similar in pre-adolescent and adolescent patients, and there appears to be little justification for adopting different therapies in these two groups.