The Big 5 Flashcards
What are the big 5 tumors?
Osteosarcoma
Lymphoma
Mast cell tumor
Melanoma
Mammary carcinoma
Signalment of Osteosarcoma
Older
Males
Large giant breeds
Which breeds are predisposed to osteosarcoma?
CDKN2A gene in rotties, Scottish deerhound
Great Dane, St. Bernard, greyhound
Where is osteosarcoma most common?
Metaphysis long bones: distal radius
Other places where osteosarcoma is common
Mandible better behavior: 70%- 1 yr survival sx alone, 20% met rate
Rib worst behavior (MST sx 3-4 m) + chemo 8 m
How is osteosarcoma dx?
FNA cytology and core bx (Combined (94%) and Jamshidi (92%))
Appendicular OSA Metastasis
> 90% micrometastases
<10% clinical met @ dx
Remove whole leg with tumor —> met to lungs
Leave primary tumor in place —> delay met
MST OSA with amputation alone
4-6 months
MST OSA with amputation + chemo OR limb- salvage + chemo
10-12m
Meds: cisplatin, carboplatin, doxorubcin, combo/ alternating
MST OSA with radiation, palliatively
4-6m
Pain management in 2-4m
Pathological fracture risk with use (patient uses leg more)
Medical tx for OSA
Biphosphanates: pamidronate (improvement in pain control in 4/10 dogs) and zoledronate (more potent)
Samarium
Medical tx of OSA
60% PR (mean ST 5m), 17% CR (mean ST 27 m)
Effect: BM suppression
What factors allow for Limb salvage in OSA
No Met
Location: distal radius/ ulna
<50% bone affected
Absence of pathologic fracture
<360° involvement soft tissues
15% catastrophic failure
OSA- stereotactic radiosurgery
High dose: 1-2d
Risk of fracture (50%)
Anatomic classification for K9 lymphoma
Multi-centric (80-85%)
GI: 5-7%
Mediastinal: 5%
Cutaneous: epitheliotropic and non
Atypical anatomical forms: hepatosplenic (aggressive), Intravascular, CNS, renal, ocular
Immunophenotypic Classification
B cell LSA: 60-80% K9 LSA
T cell LSA: 10-38%
Mixed B & T cell LSA: 22%
Null cell tumors (neither): <5%
Immunophenotyping
CD34: hematopoietic stem cells
CD45: LEUKOCYTES
CD3: T lymphocytes
CD4: T helper
CD8: T cytotoxic
CD21, CD79a/B: B lymphocytes
CD14: monocytes
Tx of choice for K9 lymphoma
C (cyclophosphamide)
H (hydroxydaunoribicin)
O (oncovin/ vincristine)
P (Pred)
12m for B cell, 6-8m for T cell
Other tx for lymphoma
None: 4-6w
Pred alone: 3-4m
Dox alone: 6-9m
Low grade lymphoma tx
if needed tx!
+/- Chlorambucil and pred if needed
Wean pred first then q 48-72 hrs Chlorambucil
Anatomic classification of feline lymphoma
Alimentary/ GI (large cell/ high grade or small cell/low grade)*
Extranodal (nasal*, renal, CNS, laryngeal & tracheal)
Large cell alimentary feline lymphoma
CHOP, COP protocols
30-60% remission
MST: 1.5-3 m
Small cell alimentary feline lymphoma
More common
Chlorambucil + prednisolone
70% remission
T cell is better
MST: >2 years
Nasal feline lymphoma RT
Mass effect in front sinus (local) responds to RT
CR: 75-95%
MST: 1.5-3 years (4m if not CR)
Nasal feline lymphoma CT
Systemic tumor
Response rate:75%
MST 2 yrs if CR
Most common cutaneous tumors in dogs
Mast cell
Lipoma
Histiocytoma
Most common cutaneous tumors in cats
Basal cell tumor
Mast cell tumor
Fibrosarcoma
Breeds predisposed to mast cell tumors
Boxers, labs, Boston terriers, pugs, beagles, schnauzers
C-kit mutations (mast cell)
Gain of function mutations in the extracellular domain of KIT, common in K9 MCT
Exon 8 &11(histologic high grade and high mitotic count)
Tandem duplications involving exon 11 and 12
CT for mast cell tumors
Vinblastine + pred
Lomustine + pred
Pallida
Stelfonta
Tx for MCT
Wound heals via seconds intention (necrotic tissue falls off)
No mets
Prognosis of mast cell tumors
1: 100% survival with sx resection
2: median survival 500 days
3: 24% @ 1 yr
2 years for low grade and <4m for high grade
What is the significance of splenomegaly in a cat?
Can causes V/D, WL → met to the skin
What is the MST for a cat that undergoes splenectomy for a cat?
1.5 yr survival
Oral melanoma
Must take bone to achieve complete margins
Oral melanoma RT
Response rate 80%
MRT: 18 m
MST: 7-12m
Higher stage, shorter remission and survival
Die of mets
Oral melanoma immunotherapy (oncept)
Transdermally IM and not preventative- xenogeneic DNA vaccine that targets tyrosinase
Dogs with stage 2 or 3 oral melanoma
Oral melanoma immunotherapy (oncept) tx repsonse
MST not reached stage 1-3 with local control and vx (>3yr)
W/o local control MST 553d
Oral melanoma prognosis
Sx alone: 6-8m
Radiation alone: 6-12 m
CT alone:6m
Radiation + chemo: 1 y
Sx or radiation + vx: >3y
What causes mammary tumors?
Hormonally influenced
Spay b4 first heat (incidence 0.5%)
B4 seconds estrus (incidence 8%)
After second (incidence 26%)
Dogs with mammary tumors
50% benign, malignant and met
Surgical tx- as much as needed
To remove tumor + OHE if intact
Cats with mammary tumors
10-15% benign, 85-90% malignant
Sx tx bilateral: complete mastectomy + OHE if intact
Prevents recurrence
Dog tx with mammary tumors
CT or RT offered when mets present, high grade, invasion lymphatics or blood vessels
Cat tx with mammary tumors
Doxorubicin improved
CT always offered
Inflammatory mammary carcinoma DD
Mastitis (litter or pseudopregnancy)
No sx
