Evaluation of follow-up investigations in children and adolescents with osteosarcoma and Ewing's sarcoma

Purpose: Determination of the respective roles of clinical investigation, l aboratory tests and various imaging techniques in the follow up of children and adolescents with osteosarcoma and Ewing's sarcoma. Method: In a retros pective monocenter analysis, charts of 72 patients with osteosarcoma and 47 patients with Ewing's sarcoma were reviewed with respect to ability of dif ferent diagnostic methods to detect the relapse, and correlated outcome. Re sults: In about 25% of relapses, a second remission could be achieved. The most sensitive methods to detect a potentially curable relapse were clinica l investigations and chest x-ray in the case of osteosarcoma and chest x-ra y and whole body scintigraphy in the case of Ewing's sarcoma. Conclusions: The different value of diagnostic methods in the follow-up of the two illne sses may be explained by the different tumor biologies and by distinct ther apeutic strategies for the treatment of relapses in the two tumor entities. However, an ongoing evaluation of current follow-up strategies is necessar y to take into account new therapeutic developments which may shift the imp ortance of certain imaging techniques.