STS Flashcards
What are some factors that can influence local recurrence of STS?
- tumour size
- tumour infiltration
- degree of surgical resection
- tumour grade
Which is the most important factor for risk of metastasis for STS?
tumour grade
Which breeds may be predisposed to FSA?
Golden and Doberman pinchers
What are some interesting features of FSA?
- tend to be in younger dogs (vs the general population for STS)
- more likely to recur after incomplete resection
- may have more mitotic counts versus other STS
- but are also more likely to be low grade
Which breeds may be predisposed to pleomorphic undifferentiated sarcoma?
- flat coated retriever
- Rotties
- Goldens
Which IHC can be used for undifferentiated pleomorphic sarcoma?
vimentin (+)
CD18 (-)
What’s the biological behaviour of undifferentiated pleomorphic sarcoma in dogs?
Aggressive.
- Often found with metastasis to SQ, LNs, liver and lungs
- 1 study reported MST of 61 days
Where are the most common locations for undifferentiated pleomorphic sarcoma?
- trunk
- pelvic limbs
- spleen
What markers are expressed by periocytes? myoperiocytes? smooth muscles?
-Periocytes: vimentin, variable degree of smooth muscle actin
- myoperiocytes: (also) desmin, calponin
- smooth muscles: smoothlin, heavy caldesmon
What’s the general cause of death for peripheral nerve sheath tumour?
patients generally die from the local disease rather than metastasis
What’s the outcome for peripheral nerve sheath tumour amendable for amputation?
- if completely removed, MST = 2227 days (6y), which is significantly better than incomplete removal (487 days, 1.3y). The overall MST = 1303 days (3.5y)
What’s the outcome of brachial plexus tumour treated with SRT?
- PFI = 240 days
- OST = 371 days
- 90% of the dogs had disease progression
- complete or partial neurological resolution
Which IHC stains can help to differentiate between well-differentiated liposarcoma and de-differentiated liposarcoma?
MDM2 and CDK4
What’s the outcome of surgical removal of liposarcoma?
- complete removal: MST = 1188 days (3.25y)
-marginal surgery: MST = 649 days (1.7y) - Incisional biopsy: MST = 183 days (6 months)
What it’s the prognostic value of histo subclassification of rhabdmyosarcoma?
- Botryoid tumours: grape-like clusters, more commonly found in the urinary bladder, may be more female, large breeds (St. Bernard). Metastatic rate = 27%
- Embryonic tumours: tend to be in younger dogs, head/neck/ retrobulbar. Metastatic rate = 50%. MST for young dogs = 2 months
- Alveolar tumours - also has a met rate of 50%
What’s the outcome of dogs with lymphangiosarcoma treated with Sx +/- RT versus no treatment?
- Sx: MST = 487 days (16m)
- Sx + RT: ST = 547 days (18m)
- No Tx: MST = 168 days
What’s the reported outcome of splenic mesenchymoma?
MST = 1 year
What’s the diagnostic yield of FNA for STS?
63-97%
What’s the dis-concordance rate of pre-op biopsy vs post-op histology?
41%:
29% underestimated, 12% overestimated
What’s the recurrence rate of incompletely removed grade I, grade II and grade III STS?
- Grade 1 = 7%
- Grade 2 = 34%
- Grade 3 = 75% (3/4 dogs)
Generally, what is the recurrence rate of low-grade STS?
- PWT: 11%, 18-20% (60-63% were incompletely removed in the entire sample)
- 28% (when <10% resected with 3cm margins)
- 21% (only 5% had wide surgical margins in the entire sample)
What are some prognostic factors predictive of local recurrence after surgery?
- large primary tumour size (>5cm)
- high grade (III)
What’s staging surgery for STS?
Can be done if the initial STS was incompletely removed. Aim for <1cm lateral margin around the scar to determine if further (larger) resection margin is needed.
- One study found only 22% of 39 incompletely removed STS had residual disease on staging surgery
What’s the outcome of incompletely removed STS treated with metronomic cyclophosphamide with piroxicam?
The DFI is significant longer in treated vs control group (but the control group had very high rate of progression)
What’s the outcome of electrochemotherapy for incompletely removed STS using bleomycin?
22 dogs
- local recurrence rate = 36%
- mean time to recurrence = 730 days (2y)
- wound dehiscence noted in 14%
Another study with 52 dogs
- RR and DFI were similar between intra-op and post-op ECT (23% and 25%, 81.5 and 243 days, respectively
- 2 CR, 1 PR, 1 SD (with ECT alone)
What’s the recurrence rate and time to recurrence for Sx, Sx + RT, or Sx+ intralesional chemo for STS?
What’s the general survival rate of STS treated with Sx and CFRT?
- overall MST = 2270 days (6y)
- 75% survival rate at 5y
- DFI 412 days to >798 days (1-2+ years)
What’s the general survival rate of STS treated with Sx and hypofractionated RT?
- local recurrence rate 18-21% (small, low grade STS)
- PFI: 698 days + (~2y+)
Outcome significantly influenced by tumour grade - Grade I PFI = 5y
- Grade II PFI = 1.5y
- Grade III PFI = 9 m (MST = 940 [2.5y])
What’s the outcome for CFRT to measurable STS?
Control rate @ 1y = 50%, @ 2y = 30%
What’s the outcome of hypofractionated RT to measurable STS?
RR = 46-50%, majority = stable disease
- mPFI: 155-419 days (5-14 months)
- MST: 206-513 days (7-17 months)
Limbs do better than head/trunk
What’s the role of adjuvant the chemotherapy for canine STS?
Controversial
- median time to metastasis 230-365 days
- no significant difference between Sx vs Sx + doxorubicin for grade III STS
What’s the metastatic rate of canine STS?
Grade 1: 0-13%
Grade 2: 7-27%
Grade 3: 22-44%
What’s the role of metronomic chemotherapy for canine STS?
may be beneficial to reduced local recurrence
- did improve ST in PRT with gross STS
- cyclophosphamide at 15mg/m2 daily can suppress Tregs
What’s the outcome of intralesional chemotherapy for canine STS?
- local recurrence rate 17-31% (more likely with grade III)
- wound complication = common –> 47-84%
What’s the reported MST for Sx alone and Sx + RT for canine STS:
Sx: MST = 1013-1796 days (2.8-5y)
Sx + RT: MST = 2270 days (6y)
but the majority of the patients (2/3) will die of unrelated causes, so many MST not reached
What’s the outcome between wide surgical vs marginal removal? Complete margin vs incomplete margin?
Wide - MST = 1306 (3.5y)
Marginal - MST = 264 days (8m)
Complete margin - MST = >1306 days (3.5y+)
Incomplete margin - MST = 657 days (1.8y)
What are some histological prognostic factors for canine STS?
- mitotic count: > 20 = 5x more likely to die
- tumour grade: MST 940 days (2.5y) for grade III Sx + CFRT
- AgNOR
- Ki67
What’s the time to recurrence for marginally removed/ non referral vs wide resection/ referral?
Marginally removed: 79 days
Non-referral: 69 days
Wide resection: 325-419 days
Referral: 274 days
With the recommended surgical margins (5cm lateral, 2 fascial planes deep), what’s the rate of complete excision and local recurrence rate for FISS?
97% complete resection
recurrence at 3y is 14%
What’s the outcome of pre-op RT for local control for FISS?
- local tumour recurrence rate 40-45%
- median time to recurrence 398-584 days (1-1.5y)
- complete resection prolong DFI but not recurrence rate
What’s the outcome of post-op RT for FISS?
similar to pre-op
- Local recurrence rate: 28-41%
- DFI: 13-37 months
What’s the outcome of post-op PRT for FISS?
MST 24 months
What’s the general outcome of Sx and RT for FISS?
- MST 600-1307 (1.5-3.5y)
- Local recurrence rate: 28-45%
What’s the outcome of RT to gross disease for FISS?
- one study used liposomal DOX as a RT senitizer –> 7/10 PR, 2/10 CR, but short lived (117 days)
- another study found PFI of 4m and MST = 7m
What’s the outcome of SRT to gross disease for FISS?
PFI = 242 days
MST = 301 days
3/11 CR; 5/11 PR
What’s the role of chemotherapy for FISS?
- undefined
- typically use doxorubicin
- can prolonged survival time, if there is gross disease still
What’s the metastatic rate and median time to metastasis for FISS?
- 0-26%
- DFI: 265-309 days
What’s the effect of chemo on curative intent Sx+ RT for FISS?
may not be beneficial for survival time, but could prolong the time to recurrence
What’s the theoretical benefit of using TKI?
- They can target the PDGFR
- no clinical beneficial results at current dosing
What’s the outcome for ETC for FISS?
Pre-op: DFI 19m
Intra-op: DFI 12m
No ETC: DFI 4m
metastatic rate only 1.7%
another study:
- post-op: recurrence rate = 29%
Which immunotherapy holds potential for FISS?
IL-2, can significantly reduce the frequency of relapse
In general, what’s the local recurrence rate (complete vs. incomplete) for FISS?
Complete: 14-22%
Incomplete: 58-69%
In general, what’s the local recurrence rate for FISS with Sx and RT?
28-45%
DFI = 13-37m
What’s the metastatic rate of FISS based on the grade?
Grade 1: 0-17%
Grade 2: 15-19%
Grade 3: 22-100%
Generally, what’s the survival of FISS treated with Sx?
MST 804-901+ days (2-2.5 y)
less aggressive Sx: MST = 395-608 days (1-1.5y)
Generally, what’s the survival of FISS treated with Sx and RT?
MST = 520 - 1307 days (1.5-3.5y)
What’s the MST for FISS with distant metastasis versus no?
with mets: MST = 165-388 days
no mets: MST = 929-1528 days (2.5-4y)
What’s the 3-2-1- rule?
- If the mass is still present after 3m,
- > 2cm
- or still growing after 1m
What’s the most common visceral STS?
- leiomyosarcoma
- most common location = spleen
What’s the local recurrence and metastatic rate of visceral STS after surgery?
- local recurrence rate = 4.7%
Metastatic rate = 23.8% on presentation, 40% at necropsy
What’s a prognostic factor for visceral STS?
MI > = to 9 had significantly shorter survival (MST 269 days).
How does the MST differ with different grades of STS in the viscera?
The MST for grade I STSs was not reached, was 589 days for grade II and 158 days for grade III.
What’s the % of recurrence based on a meta analysis for surgically removed canine STS?
- 9.8% recur even if completely removed
- 33.3% recur with incomplete margin
What’s the outcome of canine splenic stromal sarcoma post splenectomy?
in 32 dogs
- 22 developed metastasis
- mitotic count = prognostic in multivariate
- adjuvant chemo did not significantly impact metastasis or ST
What’s the outcome of using carboplatin for gross mesenchymal tumour (none oseous)?
ORR: 14.2% (4/28) –> only seen in HSA
Median PFI: 42 days
What histological parameters were associated with metastasis and tumour related death for canine smooth muscle tumours?
- Mitotic count
- Ki67
- Necrosis
- Smooth muscle tumours were most commonly found in the female genital tract, alimentary tract, and soft tissue.
- mostly benign
