SYSTEMS ONC: DERM 2 Flashcards
whats the most commonly diagnosed skin tumours in dogs
MCT
breed predispositions to mast cell tumours?
Brachiocephalic: (Boston, Boxer, Bulldog)
– Weimaraner, Shar Pei, Labrador
some characteristics of MCTs
-great imitator: look like other masses
-may fluctuate in size
-usually solitary
-occasionaly oedema
-metastasis tonodes; then; liver, spleen, BM
biologically active MCTs can cause \
GI bleeding/ulceration
Anaphylaxis
Pruritus
Bleeding tendencies
Vomiting
due to the release of which 3 substances?
histamine
heparin
other vasoactive substances
do MCT tumours exfoliate well?
yes
-therefore cytology is diagnostic 90% of time
what are the sites of metastasis( most common –> least common)
local lymph node
regional lymph nodes
spleen n liver
what is Sentinel Lymphangiography
-inject contrast into tumor to find out which nodes drain it out
regional lymph nodes should always eb assessed for metastasis. is seeing ANY mast cells normal there?
yes
what are the 2 systems for histological grading of MCT
patnaik
kiupel
describe the patnaik system for histological grading of MCT
describe the kiupel system for histological grading of MCT
what si the mean survival time for kiupel low grade tumours?
kiupel high grade tumours?
what are some limitations of the patnaik system?
kiupel system?
what negative and postiive breed prognostic factor for MCT
why is radiotherapy avoided as the SOLE therapy for MCT?
-risk of degranulation
what are 4 chemotherapy agents for MCT?
which one can be used alone as palliative?
prednisolone
vinblastine
lomustine
chlorambucil
briefly describe vinblastine
-phase specific? if so, which phase?
-toxicity?
-metabolism?
briefly describe lomustine
-phase specific? if so, which phase?
-toxicity?
-metabolism?
(non phase specific)
how do tyrosine kinase inhibitors work?
-block ATP binding site ->->-> no uncontrolled cell proliferation
C-Kit mutation is recognised in 20-30% high grade MCTs. how does this affect tyrosine kinase inhibitor treatment?
what are some other useful supportive therapies for MCT?
- H2 antagonist
- proton pump inhibitors
- sucralfate
- H1 antagonist
on multiple MCT:
-breed predisposition?
-how does it affect prognosis?
breed: golden retriever, lab, weimaraner, boxer
-prognosis is NOT affected by the number of tumours
feline MCTs are more difficult to diagnose on FNA. why?
– frequently have poorly staining
intracytoplasmic granules
– can see eosinophils and mast cells
in either MCT or eosinophilic
granuloma complex
what are the 2 forms of feline mast cell disease?
visceral vs cutaneous
what are the 2 forms of cutaneous feline mast cell disease?
mastocytic n atypical
breed predisposition for atypical mast cell disease?
siamese
some features of feline visceral MCT?
-agressive, widespread metastasis
-systemically unwell
