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Flashcards in Mast Cell tumors Deck (27)
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1

General

MOST COMMON cutaneous tumor of dogs
2nd Most common of cats (1st - basal cell tumor)

2

Systemic form of mast cell tumor?

Mastocytosis

3

Signalment - Dogs

8-9yrs
The Bs: boxer, bull terrier, bostons, bulldog :)
Pugs - multiple benign
Shar pei - more aggressive

4

Signalment - Cat

8-9 yrs
Siamese

5

Cutaneous location

Anywhere a mast cell is.
Trunk> extremities > head and neck
Cats - head and neck
Tend to be solitary

6

The great imitator

can look like any tumor
Lipoma - ill defined, soft, edematous

7

Pathophysiology

comprised of cytoplasmic granules w/ bioactive substances

8

Bioactive substance examples

-vasoactive substance (histamine, prostaglandins)
-heparin-proteoglycan matrix
-chemotactic
-proteolytic
-serotonin

9

Dariers sign

disturbed mast cell -> degranulation -> erythema, swelling, anaphylaxis, hypotension :(

10

Effects of degranulations

GI ulcers
Delayed wound healing
Hypotension
Local hemorrhage

11

Controlling degranualtion

H1 antagonists (diphenhydramine)
Warn about delayed healing

12

Work up and staging

MDB and Regional lnn aspirates
Thoracic met evaluation
Abdominal US
Bone marrow aspiration
Classification system

13

MDB and Regional lnn aspirates

only thing required if no neg prognostic factors and amenable to wide excision

14

Thoracic mets evaluation

MCT don't met to lungs.
observe lnn but not very specific

15

Bone marrow aspiration

low yield unless
Visceral MCT (rare) - BM involved 50% of the time

16

Classification system

stage 0-4
Substage
A - no systemic signs
B systemic illness

17

Histological classification Cats

Mastocytic (more common)
- compact (common), act benign. sx curative
- diffuse - aggressive
Histiocytic
- can spontaneously regress, young siamese

18

Histological classification dog

Patnik 3 tier system :/
Kiupel 2 tier system :)
-based on FNA

19

Treatment - localized skin tumor

wide excision: 2-3cm w/ fascial plane
adjunct chemo for high grade

20

Treatment - localized, non-resectable

RT alone - 1yr
Chemo to down stage then sx!
chemo alone - short lived

21

Treatment - unsuccessful excision

-Scar reversion!!
-Surveillance (only 20-30% reoccur)
-RT
-Chemo

22

Treatment - disseminated disease w/ local tumor

start w/ chemo, local excision and RT if stable and non progressive

23

Treatment Chemo

high risk dogs (mets or high grade)
red/vinblastine
Cyclophasphamide/VBL

24

Treatment Palladia

30% express c-kit mutation

25

Patient related prognostic factors

breed - better for the Bs
Systemic - worse if signs
Location
Stage - lower w/o mets is better

26

Location prognostic

SQ - better
Subungual, oral, mm associated - worse
Visceral or BM - BAD

27

Tumor related prognostic factors

Size - >5cm worse
Growth rate - slow growth is better
Molecular markers - worse w/ c-kit
proliferation rate
Microvessel density
recurrence
Histological grade - well differentiated is better
Multiple tumors - NBD