1. Objective To investigate the diagnosis of the primary chondroid parachordoma of ulna and the misdiagnosis causes and the countermeasure.

2. Results The tumor had local area of differentiated chondroid tissue.

3. Chondroid chordoma occurred in a younger age group (mean age 40. 9 years) than classic chordoma (mean age 51. 1 years).

4. The differential diagnosis among chondrosarcoma, chordoma,[sentencedict .com] and chondroid chordoma is important due to their different prognoses.

5. In older patients, fibromatosis usually lacks calcification or chondroid differentiation.

6. Conclusion: The symptoms of the chondroid chordoma occurred in pharynx and larynx are not specific.

7. Pelvic computed tomography (CT) and magnetic resonance imaging (MRI) showed a lobulated bone tumor with chondroid components in the left iliac bone.

8. The calcification varies in appearance but can be stippled and amorphous, not unlike the chondroid calcifications seen with extracranial chondrosarcomas.

9. Histopathology revealed that the tumor cells in the dermis were embedded in the eosinophilic hyaline ground substance, with chondroid appearance.

10. Post-contrast images show mild peripheral and septal enhancement typical of chondroid lesions, which have been described as variegated or having a "pepper-and-salt" appearance.

11. Chondroma of soft parts also affects the hands, but it is usually well circumscribed and has more well developed chondroid differentiation.

12. Destruction of spheno-occipital bone can be found in roentgenogram. It is difficult to distinguish chondroid chord?oma from chordoma and chondrogenic tumors which occur in this region.

13. Objective:To investigate the clinical features and outcome of patients with chondroid chordoma of pharynx and larynx.

14. Histologically, SRMS was characterized by the presence of large amounts of heavily hyalinized matrix, mimicking osteoid or chondroid tissue.

15. Conclusion:The gene expression of BMP-2 might play an important role in the formation of chondroid tissue in PA of human parotid gland.

16. In infants, fibromatosis usually involves the head, neck and proximal extremities, the background is more myxoid than chondroid , and calcification is rare.