Magnetic resonance imaging of pelvic bone tumors.

The aim of our study was to determine the value of magnetic resonance (MR) imaging in the diagnostic workup of pelvic bone tumors. We retrospectively evaluated the MR findings in 60 pelvic bone tumors. Owing to its high contrast resolution and multiplanar imaging capabilities, MR offers a clear depiction of cortical, medullar or soft tissue involvement, intratumoral necrosis, and relationship to neurovascular structures, and may be considered as the modality of choice for the staging of pelvic bone tumors. Since grading of bone tumors reaches a high accuracy on conventional radiography (CR), the value of MR imaging is rather complementary. Although the role of MR imaging in tissue characterization is mostly limited to recognition of tumoral components, accurate tissue characterization if often possible (e.g. in low-grade chondrosarcoma, eosinophilic granuloma, aneurysmal bone cyst, giant cell tumor, and chordoma). MR imaging in osteochondromas, metastases, and fibrous dysplasia remains of limited value since most of these lesions are well recognized on CR and/or CT. CR remains the first choice examination in diagnosis and grading of bone tumors, but MR imaging has significantly improved staging and tissue characterization in bone tumor imaging. The aim of our study is to determine the value of magnetic resonance (MR) imaging in the diagnostic workup of pelvic bone tumors, i.e. in staging, in differentiating benign from malignant tumors (grading), and in further characterization of tumors or tumoral components.