MCT Flashcards
In dogs treated with DRT for MCTs, what is the difference in DFI for dogs w microscopic disease vs. gross disease?
54 vs. 12 mos.
gross dz dogs live longer if mass is < 9 cm3
The local recurrence rate for dogs receiving DRT for MCTs ranges from:
5 to 20%
Using prophylactic LN irradiation for the treatment of canine MCT has what effect on MST/DFI/DFS?
No significant difference
In a study of dogs w cutaneous MCT & LN mets, what was the median DFI when given 57 Gy to local site & metastatic LNs?
41 mos
had late effects
In a study of incompletely resected Gr III MCTs using DRT of 2.88 Gy x 18, what was: MST? Median DFI? 1 yr local control % 2 yr local control %
28 mos
28 mos
65%
26%
In a study of 44 dogs with oral, perioral, & mucocutaneous MCT,
What % of dogs had LN mets on admission?
MST for dogs w LN mets vs. w/o mets?
Overall MST?
59%
14 mos vs. >36 mos (NR)
52 mos
(Hillman)
In a study of 24 dogs w MCT on the muzzle, it was found that tumors in this location have HIGHER or LOWER risk of metastasis vs. MCTs on the extremity & trunk?
HIGHER
Geiger
In a study of 17 dogs using PRT + Palladia + pred for MCTs not amenable to surgery, what was the:
ORR?
Median PFI?
Median time to max response?
76%
10 mos
1 month
In a study of 17 dogs using RT + Palladia + pred for MCTs not amenable to surgery, what % GI toxicity and hepatotoxicity?
Severity of RT-induced effects?
100%
80%
Minimal
In a study of 17 dogs using RT + Palladia + pred for MCTs not amenable to surgery, what were the effect of the presence of mutant c-KIT on:
PFI?
Survival time?
decreased PFI
no difference in ST
A significant number of MCTs have mutation in the c-KIT gene involving what exons?
8 (etracellular domain), 9, 11, 12 (juxtamembrane)
c-KIT mutation apear in 25-30@ of Gr II/III MCTs
Histamine release from MCT granules act on what receptors?
Dogs w MCT have increased plasma histamine and decreased what?
parietal cells via H2 receptors resulting in HCl secretion
plasma gastrin levels
MCTs stain positive to which 3 stains?
vimentin
tryptase
CD117 (KIT)
In dogs with undifferentiated MCTs, what % range are metastatic?
Most die within what time?
55-96%
most die ≤ 1 yr (Gr III)
What MI is used as a cut off for difference in MCT survival?
What are the MST above and below this point?
5
If MI ≤ 5, MST = 80 mos
If MI > 5, MST = 3 mos
The presence of c-KIT mutations in MCTs correlates with increase in what 3 things?
recurrence
metastasis
death due to disease
Of the following locations, in which ones do reports support association with more aggressive behavior: preputial, inguinal, subungual, mucocutaneous, muzzle, scrotal, preputial, oral.
Muzzle, scrotal, preputial
Regarding SQ MCT in the dog without c-KIT mutations, what are the 2 yr and 5 yr survival?
92%
86%
Regarding SQ MCT in the dog, list 3 histologic features associated with decreased survival.
MI > 4
infiltrative growth pattern
multinucleation
For dogs with visceral MCT, name a symptom at diagnosis that decreased survival. What was the MST for these dogs?
systemic clinical signs
3 mos
What is the recurrence rate of incompletely excised Grade II MCTs in the dog?
23%
What is the benefit to adjunct steroids in cases of complete excision of canine MCTs treated w Sx + RT?
None
Regarding canine MCTs, list 3 situations where patients should be treated as if there is a high capacity for metastasis
- Intermediate tumors w mets
- high MI
- mucocutaneous
In dogs with MCTs, prednisone as the sole tx has what ORR?
70-75%
Pred causes apoptosis, decr. growth & reproduction rate of tumor cells
NOT cytotoxic
