Chondrosarcoma – Symptoms and causes – Mayo Clinic

Chondrosarcoma is a rare type of cancer that usually begins in the bones, but can sometimes occur in the soft tissue near bones. The most common locations for chondrosarcoma tumors are in the pelvis, hip and shoulder. More rarely, the base of the skull is affected. The defining characteristic of a chondrosarcoma is that its cells produce cartilage.

https://www.mayoclinic.org/diseases-conditions/chondrosarcoma/symptoms-causes/syc-20354196