The bluish-white cut surface of this large pelvic mass arising from the right iliac wing and producing a large soft tissue mass is typical for chondrosarcoma, a malignant neoplasm of bone. Chondrosarcomas occur over a wide age range. They most often arise in the central portions of the skeleton, such as the pelvic region, shoulder, and ribs. Most of them prove to be low-grade histologically, as in this case, and are slow-growing. Men are affected twice as often as women. Low-grade chondrosarcomas are treated with wide resection.