Osteosarcoma

  • AKA Osteogenic Sarcoma

Definition

  • Primary malignant bone-producing bone tumour characterised by production of osteoid
    • ie bone matrix produced by malignant cells

Epidemiology

  • Second most common malignant neoplasm of bone after multiple myeloma
  • 20% of all malignant neoplasms of bone
  • Bimodal peak
    • Teens
    • Elderly
  • M:F – 1.5:1

Classification

Anatomical Classification

TypeSubtypes
1. CentralFurther subclassified by grade (high grade, 10-20yo, most common, or low grade) and pathology (conventional, telangiectatic, small cell, giant cell)
2. Juxtacortical (surface osteosarcoma)Low grade (30-40yo, usually low grade) or high grade
Parosteal or Periosteal
3. Intra-cortical
4. Soft tissue
5. Secondary

Aetiology

  • Strong genetic influence
    • Increased risk in children with familial retinoblastoma (500x)
    • RB 1 gene on chromosome 13
    • P53 on 17p
  • Also associated with chromosomal abnormalities such as
    • Rothmund-Thompson syndrome
    • Bloom syndrome

Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.