Osteosarcoma Flashcards
Define osteosarcoma
Primary osseous malignant neoplasm composed of mesenchymal cells producing osteoid and immature bone
What are the risk factors for osteosarcoma
Paget disease of the bone
Hx radiotherapy
Chemotherapy
Fibrous dysplasia, bone infarcts, chronic osteomyelitis, prosthetic implants
Familial retinoblastoma syndrome, Li-Fraumeni syndrome, Rothmund-Thomson syndrome
Male sex
What is the epidemiology of osteosarcoma
Most common non-haematological primary malignant neoplasm of bone in children and adolescents
Peak incidence between 13-16yo (75% <20yo)
What are the symptoms and signs of osteosarcoma
Pain
- Mild → worsens over weeks to month
- More severe at rest and at night
- Deep, dull, boring, relentless
- Occurs at the end of long bone, 60-75% in the knee
Swelling: Firm, tender, warm to the touch
Antalgic gait e.g. limping due to pain on weight bearing
Overlying skin ulceration
Limited range of motion int he adjacent joint
± signs of mets to the lung
Note: patient with severe symptoms following a minor injury, bone tumours should be considered
What are the differentials for osteosarcoma
Ewing’s sarcoma
Chondrosarcoma
Malignant fibrous histiocytoma
Giant cell tumour of the bone
Osteomyelitis
What investigations should be done for osteosarcoma
Bloods: FBC, ALP (↑), LDH (↑)
Other:
- Radiographs affected bone: radiolucent lesion with ares of mottled radiodensity and ill-defined margins, neoplasm is usually located in the metaphysis of long bone, elevated periosteum → Codman’s triangle or soft tissue calcification → sunburst appearance
- Bone biopsy + histology: Highly pleomorphic spindle cell neoplasm producing osteoid (lace-like apperance) or immature bone
- MRI: evaluate tumour extensions within the bone and soft tissue
- Bone scan/CT: staging
What is the management for osteosarcoma
- Refer to specialised sarcoma team (London)
- Treatment depends on grade
Low: wide surgical resection + reconstruction
High: surgery + chemotherapy
Mets: surgery + chemotherapy ± radiotherapy
Recurrent: surgical resection + chemotherapy
Post: OT, PT, dietician, orthotics/prosthetics, support (sarcoma UK)
What are the complications of osteosarcoma
Recurrence
Lung mets
Bone mets
What is the prognosis for osteosarcoma
Prognosis has improved with chemotherapy: 75-80% 5-year survival rates
Likelihood of local recurrence is 5-7% and is related to resection margins and response to chemotherapy
5-year survival for metastatic disease is 20-40%
Long-term post-relapse survival is <20% in those with recurrent osteosarcoma
Prognostic factors: detectable primary mets and poor histological response to chemotherapy
What is the difference between osteosarcoma, Ewing’s sarcoma and chondrosarcoma
Osteosarcoma = forms bone
Ewing’s sarcoma = forms mesenchymal tissue (neuroectodermal)
Chondrosarcoma = forms cartilage (occurs in those >40yo)
What is Ewing’s sarcoma
Primitive Neuroendocrine Tumour (PNET) / malignant, small round blue-cell tumour
What the aetiology and epidemiology of Ewing’s sarcoma
<25y, median 15y
Associated t (11:22)(EWSR1/FLI1) (q24; q12)
Long bones of arms, legs, chest, skull and trunk
What are the signs and symptoms of Ewing’s sarcoma
Mass or swelling and bone pain
Malaise, fever, paralysis (may precipitate osteomyelitis)
What investigations should be done for Ewing’s sarcoma
XR: bone destruction with overlying onion-skin layers of periosteal bone formation
Biopsy: small round blue cells
CT/PET/MRI: staging
What is the management for Ewing’s sarcoma
Specialised sarcoma team (London) management
Surgery (limb-sparing surgery ± amputation) + chemotherapy (VIDE) + radiotherapy
Post-treatment: OT, PT, dietician, orthotics/prosthetics, support
