The relationship between the clinical status skeletal involvement, frequency of metastases and histopathological grading of osteosarcomas 18 children and adolescents and abnormal DNA content (aneuploidy) was analysed. Our findings demonstrate a correlation between Index DNA (DI), percentage of aneuploidy population to histopathological grading and prognosis. No significant correlation was found between aneuploidy and the site of skeletal involvement.