A 10-year-old boy presented with bloody rhinorrhea of one month duration from the right side of the nasal cavity. On nasal endoscopy, a large, polypoid mass was observed to fill the right nasal cavity causing deviation of the lateral nasal wall to the right. CT showed a lobulated, low attenuating mass with ring and arc calcifications in the right nasal cavity and nasal septum, measuring about 4.9 ×3.3 ×2.9 cm (). The mass extended beyond the nasal septum into the right ethmoid sinus and had caused pressure erosion of the adjacent bony margins of the cribriform plate and medial orbital wall. However, no definite bony destruction was demonstrated. After intravenous infusion of contrast medium, subtle internal septal enhancement of the mass was observed. Coronal and axial T2-weighted MR images (TR/TE, 4128/100) revealed more accurately the anatomical relationships of the mass (), which was located in the right nasal cavity and nasal septum, and extending into the right ethmoid sinus. The mass had displaced and compressed the right medial orbital wall laterally and the cribriform plate superiorly, and mass was homogeneously hypointense on T1-weighted images () and heterogeneously hyperintense on T2-weighted images (). It showed mainly peripheral and septal-like enhancement on contrast-enhanced T1-weighted images and regional inhomogeneously strong enhancement at its anterosuperior portion (). Areas of low signal intensity were seen on T2-weighted MR images (), which corresponded to matrix mineralization on CT images (). An endoscopic biopsy was performed in the nasal cavity, and the preliminary pathologic diagnosis was of myxoid chondrosarcoma or chordoma, due to the presence of a cord-like cellular arrangement with a myxoid background. Whole body PET-CT with a low-dose CT protocol was performed at the 17th day after biopsy. PET-CT revealed a mild F18-fluorodeoxyglucose (FDG) uptake area (pSUV, peak standardized uptake value = 2.7) in the lesion without a definite metastatic lesion ().\nThe patient underwent subtotal resection of the mass; some residual mass remained in the ethmoid sinus and nasal septum. The removed tumor was a pale gray, soft to firm, polypoid mass measuring 4.7 ×3.0 ×3.0 cm. Histologically, there were scattered pleomorphic chondroblasts with thin anastomosing strands surrounded by a myxoid stroma; cellular areas were arranged in cords (). The presence of a characteristic cord-like cellular arrangement resembling chordoma and strong positivity for S-100 protein and vimentin led to a final diagnosis of myxoid chondrosarcoma. The low cellular atypia, few mitoses, and low cellularity observed represented a low grade tumor. We could not prove the presence of the specific t (9; 26) translocation which is regarded as another pathognomonic feature of myxoid chondrosarcoma because the RT-PCR technique and primer required were unavailable.\nAfter surgery, the patient underwent radiation therapy on the remaining primary tumor, and subsequently the remaining tumor showed a decreased size and enhancement on follow up CT.
A 52-year-old man presented with a 6-month history of a soft tissue mass around the right axillary region, which appeared to be gradually increasing in size. He had no history of any major illness or trauma. Physical examination showed a nontender mass measuring 3×3 cm with a hard-elastic consistency that was palpable over the right axillary area. The mass was well demarcated from the surrounding structures, and no skin changes or neurovascular deficit were present.\nPlain radiographs showed soft tissue swelling with stippled calcification on the right medial axillary region (). Pathologic findings showed no osteolysis or cortical destruction around the lesion. CT also depicted calcification without an osteolytic lesion, and without thinning or expansion of the cortex of bone around the lesion (). In MR images, the peripheral area exhibited high intensity in both T1-weighted and T2-weighted images, whereas the central area exhibited low intensity in both (). Enhanced MRI revealed peripheral and mild speculated enhancement around the lesion, which was regarded to be due to calcification (). Chest and abdominal CT and a bone scan showed no evidence of metastasis.\nThe mass, lying on the latissimus dorsi muscle was excised. The tumor measured 3×3×3 cm in dimensions and appeared to be well-encapsulated. The longitudinal section of the resected mass revealed tan-white tissue with central and focal areas of hemorrhage and necrosis (). The histologic examination was consistent with a diagnosis of mesenchymal chondrosarcoma. The tumor consisted of undifferentiated small neoplastic cells, varying from round to spindle-shaped, and interspersed with well differentiated foci of cartilaginous tissue ().\nThe patient underwent a course of postoperative external beam radiation (6,000 cGy over 30 treatment sessions). At 1 year after surgery, the patient had remained free of local recurrence or metastasis.