Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
38 Cards in this Set
- Front
- Back
|
sarcomas are ____ in origin |
mesenchymal |
|
|
they can be derived from what tissue types |
bone cartilage fat muscle vascular tisse |
|
|
sarcomas often spread ___________ and met to the _____ |
hematogenously lungs |
|
|
soft tissue sarcomas develop in soft tissue and can occur in almost any organ - except which tissue types |
hematopoietic epithelial |
|
|
T/F: canine sarcomas are a group of tumors that are very discrete from one another |
False; they are a group of tumors w/ similar features and similar clinical behaviors |
|
|
7 types of soft tissue sarcomas |
fibrosarcoma myxosarcoma liposarcoma malignant fibrous histocytoma mesenchymoma |
|
|
2 soft tissue like sarcomas |
synovial cell sarcoma lipomas |
|
|
what are the common features of the soft tissue sarcomas (even if cell origin is different) |
-- pseudocapsulated, soft to firm -- local recurrence w/ incomplete resection -- hematogenous mets to the lungs (when they met) -- bulky tumors do not respond well to chemo or radiation alone |
|
|
why is knowing about the pseudocapsule so important |
the tumor may look incapsulated in surgery, but it is important to know that cells can be beyond the capsule |
|
|
what is the incidence of STS in the dog |
35/100,000 |
|
|
what are some associated causes of STS |
radiation trauma FB orthopedic implants parasite -- splrocra lupi |
|
|
most solitary tumors are seen in middle-aged to older dogs, what is the exception |
rhabdomyosarcoma seen in young dogs |
|
|
which breed is predisposed to STS |
generally no breed or sex predisposition |
|
|
would a STS involve the epidermis |
no, but it may become ulcerated as it is stretched by the tumor. |
|
|
how would a STS be diagnosed |
cytology biopsy |
|
|
what is the down side of cytology for STS |
often undiagnostic - "spindle cell proliferation suspect STS" |
|
|
what type of biopsy would be done |
incisional or needle |
|
|
why is biopsy helpful |
grading: differentiation and invasion -- prognosis and treatment planning |
|
|
what other diagnostics would be done related to the STS |
MDB: assess for anesthesia and evidence of systemic disease Primary tumor size mets: CT, LN FNA, abdominal US |
|
|
how would a STS be treated |
surgery is the treatment of choice gross tumor + biologic margins (3 cm lateral and 1 fascial plane deep) |
|
|
why do you need wide margins |
pseudocapsule |
|
|
what would you do if you didn't get clean margins |
recommend re-excision or radiotherapy |
|
|
what about clean, but close margins (<5cm) |
makes you nervous b/c cells can go beyond the capsule |
|
|
how are STS graded |
combined score of differentiation, mitotic score and tumor necorsis score |
|
|
what kind of sarcomas do only cats get |
vaccine associated sarcomas |
|
|
many of the vaccine associated sarcomas are what cell type |
fibrosarcoma |
|
|
VASs are associated with what type of vaccine |
no clear association w/ adjuvaunt vaccines, single manufacturer or vaccine type
ALSO associated with NON-vaccine needle sticks |
|
|
what is the theory behind VAS formation |
uncontrolled fibroblast and myofibroblast proliferation +/- immunologic factors result in tumor formation |
|
|
why are we concerned about VAS |
they are biologically more aggressive (a higher percent of them are grade 3) |
|
|
what is the 1-2-3 rule |
a lump should be investigated when -- it has been present at a vaccine site for 3 months -- at any time it is larger than 2 cm in diameter -- it is increasing in size more than 1 month after vaccination |
|
|
what diagnostic work up would be done on a suspect VAS |
- cytology or incisional biopsy - MDB: make sure the patient is healthy to go to surgery - Assess for met: 3 view rads, LN aspirates, abdominal US w/ hind limb/pelvic dz - assess primary tumor size and extension |
|
|
how would these tumors be treated |
surgery -- CT planning first radiation after surgery +/- chemo |
|
|
why is CT important before planning |
these tumors are poorly incapsulated and very infiltrative |
|
|
what type of margins would you take |
5 cm and 2 fascial planes deep (not always possible in the cat)
this is going to be a gnarly surgery --- refer! |
|
|
how does the radiation field compare to the surgical field |
it is larger -- it includes the surgical field and adds some |
|
|
what is prognosis for a VAS |
marginal resection: 79 day wide /radical resection: ~400 d sx + radiation: 600 - 1300 day |
|
|
what about chemo in these patients |
we don't really know if it helps |
|
|
how common are spontaneous feline sarcomas |
not very common w/ a low met risk (tx: wide surgical margins and radiation) |
