Extra-axial Chordoma of the Sternoclavicular Joint

Chordomas are rare, slowly growing, aggressive primary bone tumors that originate from notochord remnants and occur almost exclusively in the axial skeleton. Here, we describe a patient with an enlarging right-sided neck mass that was later diagnosed as a sternoclavicular joint chondroid chordoma. En bloc surgical resection was accomplished with negative margins. The patient continues to do well 15 months after resection without radiotherapy. This case highlights the importance of considering a wide differential in managing sternoclavicular joint tumors.