The CT and MRI Findings of Sacral Mesenchymal Chondrosarcoma : A Case Report

Mesenchymal chondrosarcoma is a rare malignant tumor. It may exhibit as a skeletal or extraskeletal tumor and usually contains calcified deposits. A lesion arising from sacrum is extremely rare. We present a 17-year-old male patient with clinical manifestations of lower back pain and sciatica. Computed tomography and magnetic resonance images of the patient depicted a poorly demarcated sacral tumor with a large extraosseous soft tissue component, but without calcification. Multiple small foci of lung, bone, and lymph node metastases were also found on staging CT images. CT guided biopsy and lumbosacral laminectomy (L5-S3) with partial removal of extradural mass for decompression were performed. The histopathological diagnosis was mesenchymal chondrosarcoma. However, the tumor had poor response to adjuvant chemotherapy and radiation therapy during an 8-month follow-up.