MCT Flashcards
Was there any difference between wound healing complication rates between marginally excised MCTs and STS?
(Cockburn, Javma, 2021)
No, the wound healing complication rate for the MCT group was 29% and for the STS 31%.
The use of subdermal plexus flaps contributed to wound healing complication and increased time to complete healing.
Are dogs undergoing surgical excison of MCTs at increased risk of incisonal complications?
(Iodience, JAVMA, 2021)
No, MCT 13%, STS 14%
chmotherpy < 30 days after surgery should be used with caution, corticosteroid use seems safe
In macroscopic MCT are c-kit mutational status and KIT localisation predictive of treatment response to TOC in comparinson to VBL?
Do dogs with c-kit mutation have better outcome when treated with TOC?
(Weishaar, JVIM, 2018)
There was no sig. difference between PFS (TOC vs. VBL, 95 vs 78 days) and MST (159 vs 241 days)
The response rate was also similar: VBL 30%, TOC 46%
Dogs with c-KIT mutation had a worse outcome then without
In a recent study another gene mutation has been discovered that has maybe a role in the development of MCTs. What is this gene and what kind of effect does it have on the outcome?
(Vozdova, VCO, 2020)
Mutation in 17% of MCT of GNB1 gene (G-protein beta subunit)
more mutation in subcutaneous MCTs (approx. 44%)
might be correlated with better survival
Is there KIT mutation in subcutaneous MCTs?
What is the methylation status of KIT and TP53 in cut and subcut MCTs?
(Vozdova, VCO, 2019)
1 reported case on exon 8, not associated with worse survival
Usually promoters unmethylated
There was more methylation in subcut MCTs–> maybe reason for better prognosis
What is pKIT? How can it be meausred?
With what prognostic factors was an association demonstrated?
(Thamm, VCO, 2019)
phosphorylated KIT, activated KIT receptor that can be measured with IHC
Its is associated with KIT cytoplasmatic expression, MI and histological grade (higher grade 3), NOT associated with c-KIT mutation (this means that the receptor gets activated through other pathways and not through the mutation)
pKIT was the sole predictor of OS!
Is there an increased hematological toxicity in dogs recieving RT+ VBL/pred concurrently?
(Stiborova, JSAP, 2019)
No, it was about 20% as previously reported
What was the outcome of a paper examining the use of lateral proportional margins with a 2 cm upper limit in low and high grade MCTs?
What was the recurrence rate?
Was there any difference between the groups?
(Saunders, VCO, 2020)
Complete excision in 95% of the cases, 3% recurrence all in high grade tumors (1 was incomplete)
no diff. between low and high-grade tumors for complete margins
Tumor grade and size did not influence the HFTM
DFI for low grade not reached, for high grade also not reached, but those who died median 228 days
In a study comparing 2cm proportional margin and 3cm overall margins, what was the difference between the groups?
(Chu, JAVMA, 2020)
There was no difference 93% vs 92% complete excisions
No diffrence between tumor diameter and location between the groups
What is the presentation and prognosis of dogs younger than 1 year with MCT?
(Rigas, JSAP, 2020)
66% female, solitary MCT (mostly head), Labs and Goldens overrepresented
Prognosis is good, all of them alive, although most of the tested animals had c-kit mutation on exon 11, all were ki67 above the cut off
(4 dogs grade III or high grade, 3 MI above 5)
Treatment was variable, but surgery was mostly included
What patient and tumor factors were/were not associated with high histological MCT grade?
(Reynolds, VCO, 2019)
Age, gender, neuter status, tumor size at excision –no sig. difference in risk
Pugs and Goldens were at decreased risk, Shar peis at increased
Inguinal area was associated with occurence of high grade tumors
What does a mutation on exon 8 in cutaneous MCTs associated with?
(Bouvien, Vet Pathol, 2021)
Better prognosis
Should be screened for after surgery to see if adjuvant therapy needed
In which case is the use of MCM7 (or Ki67) use recommended?
Berlato, VCO, 2018
MCM7 sig. associated with prognosis independently of histo grade
It is recommended together with Ki67 in Grade II, low Kiupel and low MI (<5)
MI was found to be not sensitive (39%) but very specific (99%)–> therefoe it may miss some aggressive tumors
MCM7 approx 83 % sens., 87% spec (similar to Ki67)
Was there any significant difference in acute and late toxicity in dogs treated with RT for microscopic and macroscopic MCT?
(Blackwood, VCO, 2018)
No.
There was no difference in irradiating microscopic vs macroscopic MCTs in the severity of the AEs. All dogs developed acute, but none late AEs.
All were treated with prednisolone and H2 blockers or omeprazole
2 dogs had hematemesis
On dogs with head MCTs the pretreatment with prednisolone lead to grade 2 and 3 AEs–> presumably due to more sensitive sights prone to bacterial infection
Is the use of intralesional triamcinolone safe and effective for the treatment of MCTs?
(Case, JAVMA, 2018)
It is safe, the response rate was 67% (mostly it was combined with other therapies), but it was short (63 days)
It might be used for cytoreduction in places not amable for wide resection
It can be given concurrently with other cytotoxic therapy or RT
