osteosarcoma

Definition

Intermediate grade chondroblastic osteosarcoma arising from surface of long bones

Epidemiology

Extremely rare

- 1% of all osteosarcomas

- 25% of surface osteosarcomas

Age 15-25

Location

Typically anterior proximal tibia

- diaphysis of major long bones

- humerus

Pathology

1. Osteosarcoma

Second / Third decade, M>F

- calcaneal

- diagnosis often delayed

- treat with radical resection

2. Chondrosarcoma

Middle age or older

- slow growing

- malignant change of osteochondroma / enchondroma

- treat with wide / radical resection

3. Ewing's

Lytic expansile mass in a MT

- can be anywhere

DDx

Primary

Benign

Osteoid Osteoma

Osteoblastoma

Osteochondroma

ABC

Hemangioma

Giant Cell tumour

EG

Malignant

Chordoma

Ewings

Osteosarcoma

Chondrosarcoma

Lymphoma

Multiple myeloma

Secondary

Leukaemia