• Rare tumor
  • Most common in 10- to 30-year-olds
  • Poor prognosis
  • Radiographic pattern usually lytic, destructive, and permeative
  • Microscopic appearnce
    • Small cells juxtaposed to lobules of chondroid tissue
    • May have a hemangiopericytomatous appearance
    • May be difficult diagnose on biopsy if cartilage component has not been sampled
  • Surgery is treatment mainstay
    • Some centers use chemotherapy based on osteosarcoma or Ewing sarcoma protocols as adjuvant therapy