Mast Cell Tumors Flashcards
(20 cards)
How are MCTs diagnosed?
PE: abdominal palpation
FNA
Local LN palpation + FNA
Mast cell tumor
What criteria must be met in order to skip additional staging of MCTs?
Lymph node is negative
No negative prognostic factors (location, breed, recurrence, ulceration, GI signs
“Appropriately large” surgery is feasible and will not require radical or very expensive procedures
What are prognostic factors associated with MCTs?
Histologic grade
Clinical stage
Location
Growth/proliferation rate/ulceration
What are characteristics of a low/intermediate grade MCT?
Low risk of metastasis
Aggressive local invasion of tissue
Still needs aggressive local therapy
What are characteristics of a high grade MCT?
Higher risk of metastasis
Shorter historical survival post-surgery
Local therapy alone suboptimal
How is location associated with prognosis of MCTs?
Mucous membranes have a lower MST than haired skin
What tests are used to stage canine MCTs?
CBC/chem/UA (anemia, BUN, hypoproteinemia = GI ulcer?)
Thoracic rads - check LNs
FNA of regional LNs
Abdominal US
+/- tumor biopsy
What tests are NOT useful with MCT staging?
Buffy coats
Aspirates of structurally normal spleen/liver
BM aspirate
What are the general treatment options for MCTs?
Wide surgical excision (3m margin)
RT post cryoreduction
Chemo for “high risk” or if RT/sx not an option
What post-operative therapies are recommended for MCTs of grade I - III?
MCT Prognosis: Surgery
Often sufficient therapy for low or intermediate grade MCT
MCT Prognosis: Radiation Therapy
Most effective in the context of microscopic disease
85-95% 2-year control for incompletely resected intermediate grade MCT
12 month MST for gross MCT
What are indications for chemotherapy with MCTs? (4)
High risk of metastasis - high grade tumors, “historically unfavorable” location, lymph node metastasis, multiple tumors
Does the number of cutaneous MCTs influence outcome?
No
What are the 3 forms of feline MCTs?
Cutaneous
Visceral (splenic, GI)
Prognosis: Splenic MCT in Cats
MST following splenectomy is 18 months
Prognosis: Intestinal MCT in Cats
2/3 metastatic at diagnosis
Chemo may improve outcome (MST = 240 days)
How are feline MCTs treated?
Chemotherapy (CCNU, pred/vinblastine, palladia)
What is palladia?
KIT receptor tyrosine kinase inhibitor
GI adverse effects
