The aim of the study is to assess the accuracy of dynamic contrast enhanced and diffusion-weighted MR Imaging in evaluating response to chemotherapy in osteosarcoma.

Dynamic contrast-enhanced and diffusion-weighted magnetic resonance imaging have the potential to measure early cellular and vascular changes that occur in response to chemotherapy and could therefore be early predictors of therapeutic response.

Aim of our study is to assess the accuracy of dynamic contrast enhanced and diffusion-weighted MR imaging in evaluating response to chemotherapy during the preoperative treatment of osteosarcoma. Patients will undergo dynamic contrast-enhanced and diffusion-weighted magnetic resonance imaging before, during and after chemotherapy.

Our long-term goal is to use these imaging techniques to develop non-invasive methodologies that would be better predictors of tumor response than the current clinical standard and earlier predictors than histological evaluation of the whole tumor.

Inclusion Criteria:

• Histologically confirmed diagnosis of osteosarcoma of all entities
• Written informed consent of patient

Exclusion Criteria:

• No written informed consent
• Contraindications to MRI (pacemaker, aneurysm clip, mechanical and/or electrical device or metallic fragment, severe claustrophobia)
• Severe, active co-morbidity
• Major medical illnesses or psychiatric impairments

German, Austrian and Swiss patients with an osteosarcoma will be entered into the study.