Sarcomas (Yr4) Flashcards
what is a sarcoma?
malignant cancer that arises from cells of mesenchymal origin (bone, connective tissue, nerves, blood vessels…)
what is the cell of origin of an osteosarcoma?
bone
what is the cell of origin of a soft tissue sarcoma, fibrosarcoma or myxosarcoma?
connective tissue
what is the cell of origin of a haemangiosarcoma?
blood vessels
what is the cell of origin of a rhabdomyosarcoma?
striated muscle
what is the cell of origin of a lipoma?
fat
what is the cell of origin of a chondrosarcoma?
cartilage
in general how invasive are sarcomas?
typically quite locally invasive
which sarcomas are generally high metastatic risk?
osteosarcomas
haemangiosarcomas
histiocytic sarcoma
what is the difference between stage and grade?
grade… histological features and likely behaviour (invasion, vascularity, necrosis…)
stage… the extent of the disease and how far it has spread
what is the predilection site fir metastasis of all sarcomas?
lungs
what are the ideal margins for surgical excision of soft tissue sarcomas?
3cm lateral and 1 fascial plane
will a sarcoma reoccur if you remove it with incomplete/narrow margins?
depends on type and grade but most sarcomas have a high probability of reoccurrence
when is metronomic chemotherapy used?
continuous low dose therapy after excision of a sarcoma
what is the 3-2-1 rule associated with feline injection site sarcomas?
investigate any masses…
present for longer than 3 months
greater than 2cm in diameter
continues to increase in size 1 months after injection
how are feline injection site sarcomas treated?
surgical extraction… 5cm lateral and 2 fascial planes deep
what dogs are predisposed to osteosarcomas?
older large breed dogs
what are the radiographic changes seen with osteosarcomas?
bone lysis
soft tissue swelling
new bone (sunburst appearance)
periosteal elevation
long zone of transition
how are osteosarcomas treated?
amputation, analgesia
how invasive and metastatic are haemangiosarcomas?
highly
