Until the last decade the role of nuclear medicine procedures in the work up of soft tissue tumors had been quite modest, for various reasons. Firstly, soft tissue tumors are not a common type of tumor: they only account for about 1 % of all malignancies [86]. Secondly, nuclear medicine procedures attempted in the past for this type of tumors yielded rather disappointing results, among other reasons due to technical limitations and a limited choice of appropriate radiopharmaceuticals [52]. Clinicians then gradually abandoned nuclear medicine examinations for this application and relied more and more upon the increasing armamentarium of nonradioactive imaging modalities: ultrasound, computed tomography (CT), and, most recently, magnetic resonance imaging (MRI).