4. Osteosarcoma Flashcards
Undifferentiated connective tissue and forms of neoplastic osteoid
Central Osteosarcoma
other types of osteosarcomas
- Multicentric
- Parosteal
- Secondary
- Extraosseous
Second m/c primary malignant bone tumor
Central Osteosarcoma
20% of all primary bone tumors, mostly in 10-25 year olds.
Central Osteosarcoma
Painful swelling at site of lesion (85%), with weight loss, fever, and cachexia
Central Osteosarcoma
May take ______ or longer to DX the central osteosarcoma tumor
6 months
Central osteosarcomas likes ____ bones,
long
primarily knee and shoulder
• 58% of Central osteosarcomas tumors occur around the ____.
knee
Typically located in metaphysis
m/c affected structure in spine from osteosarcoma
Vertebral body
comp. Fx
Secondary Osteosarcoma arise in Paget’s bone at __ %
44
If patient has Paget’s disease measure -__________ as a baseline study
alkaline
phosphatase
Will Alkaline Phosphatase
levels return to normal with removal of
tumor?
yes
__ % of Central osteosarcomas are neoplastic sclerotic bone, __ % are Purely lytic
and __ % are Mixed.
50, 25, 25
Pulmonary metastasis in osteosarcoma via hematogenous
route
Cannonball Metastases
ossfified
Cannonball metastases represents
sarcomatous pulmonary bone growths
Common subpleural nodules that have undergone
excavation –> rupture
Spontaneous Pneumothorax
Skeletal Metastasis may occur, called
Skip lesions
75% of Central Osteosarcomas are in
metaphyses of long bones
Central Osteosarcomas are m/c at the
•
•
distal end of femur
and Proximal tibia and humerus
what usually acts as barrier to spread?
Physis
- Focal lesion in metaphysis
- Mottled, permeative lesion
- Poorly defined zone of transition
- cortical distruption
Central Osteosarcoma
Dense ivory or sclerotic lesion filling medullary
space
Central Osteosarcoma
Spiculated or Sunburst periosteal reaction
in soft tissue and occasionally see Codman’s Triangles
Central Osteosarcoma
Ill-defined permeative mixed lytic/blastic lesion
can cross the growth plate
Osteosarcoma
soft tissue mass and spiculated periosteal reaction indicates
rapid growth
seen with large sclerotic
lesions
Cumulous cloud formation
Large soft tissue mass formation that may contain
ossification
Amputation if accessible and there is no…
Radiotherapy for local pain control
metastasis
Average time between recognition of pulmonary
disease and death is
6 months
Lytic presentation is rapidly
fatal
radiograph of osteosarcoma of distal femoral shaft
- aggressive periosteal
changes - Codman triangles
- soft tissue mass
Sagittal T1-weighted MRI osteosarcoma
- abnormal signal intensity is present throughout the visible shaft and metaphysis - growth plate has limited extension of the tumor - Cortical destruction
Radiograph of femur with osteosarcoma shows
a typical
Codman triangle
Mixed sclerotic/lytic primary bone
lesion at the metaphysis with pathological fracture
central Osteosarcoma
- Cystic expansile lesion of the distal metadiaphysis that abuts the epiphyseal plate
- intermediate signal on T1, and high on T2 images
central Osteosarcoma
Rare, Independent lesions occuring simultaneously
Multicentric Osteosarcoma
Multicentric Osteosarcoma occur in what age group?
5-10
- primary lesions
with Rapidly fatal course - blastic lesions which increase alkaline phosphatase
- Pulmonary metastasis occurs early
Multicentric Osteosarcoma
- Multiple blastic lesions
- Bilateral and fairly symmetric
- Metaphyseal
Multicentric
Osteosarcoma
Slow growing well-differentiated osteosarcoma located on bone surface in juxtacortical location
within periosteum in 30-50 yo
Parosteal Osteosarcoma
50% of Parosteal Osteosarcomas occur where?
posterior surface of distal femur
Average size of Parosteal Osteosarcoma
10 cm
- Lobulated, sessile, bony mass
with broad based attachment to bone - Cleavage plane = 1-3mm
Parosteal Osteosarcoma
helpful imaging for Parosteal Osteosarcoma?
CT
DDx for Parosteal Osteosarcoma
Myositis Ossificans Traumatica (MOT)
Parosteal Osteosarcoma
vs Myositis Ossificans Traumatica (MOT)
Sarcomas are denser centrally grows over time (exact opposite for MOT)
Malignant degeneration of benign disorders to osteosarcoma
Secondary Osteosarcoma
who is susceptible to Secondary Osteosarcomas
Watch Dial Painters Ingested radium
(10-15 years later)
Secondary Osteosarcoma looks like osteosarcoma with the
Permeative, motheaten, periosteal rxn, soft tissue mass
In 1926, _____ was considered a
miracle elixir
radium
avg latent period for Post-radiation Sarcoma
15
used for Angiography in 1950’s
Thorotrast Injection
Large soft tissue mass not adjacent to bone that m/c affects the thigh in 30-50 yo
Extraosseous Osteosarcoma
Common pulmonary metastasis in
Extraosseous Osteosarcoma
Non-contrast CT of the chest showing multiple, subcentimeter, calcified pulmonary nodules consistent with
metastatic Paget’s sarcoma