Primary Bone Tumors

What are the most common primary malignant bone tumors?
  • Osteogenic sarcoma
  • Ewing's sarcoma
  • Fibrosarcoma
  • Chondrosarcoma

Primary bone tumors are rare, accounting for less than 1% of all malignant tumors.

What are the useful imaging modalities to investigate primary bone tumors?
  • Plain radiographs
    • Plain radiographs can often predict the probable histology of a potentially malignant bone lesion.
  • MRI
    • MRI is the imaging procedure of choice to evaluate primary bone tumors.
    • MRI is invaluable in surgical planning as it demonstrates the intraosseus and soft tissue involvement of the tumor and tumor extension.
    • MRI is also helpful in evaluating possible malignant degeneration of osteochondromas by allowing accurate measurements of the cartilage cap.
  • CT
    • CT scans are generally less useful than MRI for assessing primary bone tumors.
    • CT is helpful in defining the integrity of the cortex and distribution of calcification.

Image Atlas for Primary Malignant Tumors

What are the imaging findings of primary bone tumor?
  • Osteogenic sarcoma
    • Destruction of bone
    • Sunburst appearance
    • Periosteal elevation
      • MR
      • Bone scan
    • Sclerosis

Osteogenic sarcoma fibula

Destruction of bone with sunburst appearance.

Osteogenic sarcoma Tibia

  • Sunburst appearance
  • Aggressive periosteal reaction
  • Sclerosis


Osteogenic sarcoma tibia

Osteogenic sarcoma tibia


  • Mass with calcification
  • On plain radiographs, chondrosarcoma is a fusiform, lucent defect with scalloping of the inner cortex and periosteal reaction.
  • Extension into the soft tissue may be present as well as punctate or stippled calcification of the cartilage matrix.

Chondrosarcoma Inferior ramus of pubis

Calcified cartilaginous mass arising from a flat bone in a patient with unfused epiphyses.


MR: White arrows : Mass with calcification. Arrowhead is pointing to femur.

  • Ewing's Tumor

    • Lytic lesion
    • "Onion peel" appearance of periosteal reaction

Ewings Sarcoma Femur

  • Arrow : Lytic lesion
  • Arrowhead: "Onion peel" appearance of periosteal reaction. Layers of periosteum