[Soft-tissue sarcomas of the extremities. Their assessment with magnetic resonance]

MR imaging was performed on 38 patients with suspected malignant soft-tissue tumors of the extremities. MR diagnostic accuracy was compared with that of other methods. All patients underwent surgical control. In 7 cases MR imaging was employed to demonstrate the tumor response to antiblastic local perfusion. Lesion identification, extension, compartmental evaluation, bone and vascular involvement were the diagnostic parameters considered. In all cases MR imaging detected the lesion, correctly showing the intracompartmental (16 patients) or extracompartmental (22 patients) extension. In 2 out of 6 cases MR imaging did not demonstrate bone invasion, and in 1 case vascular involvement could not be assessed. MR diagnostic accuracy was superior to that of other techniques. Nonetheless, a diagnostic protocol was proposed for the local staging of malignant soft-tissue tumors of the extremities where some diagnostic limitations of MR imaging are taken into account--i.e., inconsistent evaluation of bone and vascular involvement. Plain X-rays and US are the imaging modalities of choice, whereas MR imaging is to be a second-choice diagnostic technique before biopsy. Thus, MR imaging replaces CT, while angiography is to be used in selected cases, where MR imaging is not diagnostic due to vascular involvement.