Nasal and Oral Tumors Flashcards
Are oral melanomas of dogs more often benign or malignant?
Malignant
What % of oral melanoma dogs have bone involvement?
Over 50%
Where do oral melanomas commonly metastasize to?
Tonsils and regional LNs (also lungs)
How do you diagnose an oral melanoma in a dog?
Biopsy
What is the MST for a canine oral melanoma with no treatment?
2 months
What surgical options are there for treating canine oral melanoma/SCC?
Mandibulectomy or maxillectomy
What is the MST for a canine oral melanoma treated with mandibulectomy/maxillectomy?
6-12mo
By how much does chemotherapy treatment after surgery increase MST for canine oral melanomas?
Increases MST to 2y
What are prognostic factors assoc. w/oral melanoma in dogs?
Size, location, stage, and local recurrence
What is the 2nd most common oral tumor in dogs?
Squamous cell carcinoma
What % of canine oral SCC have bone involvement?
Over 70%
Is metastasis more common with canine oral melanomas or SCC?
Melanoma
How do you diagnose a canine oral SCC?
Biopsy
What is the MST for a canine oral SCC treated with mandibulectomy and maxillectomy?
18mo
How does chemotherapy affect a canine oral SCC?
Does not result in good survival times
Combination of surgery and what other treatment modality increases survival time of canine oral SCC by two?
Radiation therapy
What is the most common malignant oral tumor in dogs?
Oral malignant melanoma
What dog breeds are more commonly affected by oral malignant melanomas?
Chows, GR, poodle, cockers
What is a melanoma?
Tumor of melanocytes
What % of oral malignant melanomas are amelanotic and may not contain any melanin?
1/3
What are other common places for melanomas to occur in dogs?
Cutaneous (usually benign) Nail beds (50% malignant)
Once a diagnosis of oral malignant melanoma is made, what are the tests done to determine staging?
MDB, regional LN aspirates, thoracic rads
How can radiation therapy be used to help treat oral malignant melanoma?
Can shrink tumor or temporarily slow its growth
Which chemotherapy agents have mild efficacy in temporarily shrinking oral malignant melanomas?
Platinum agents (carboplatin and cisplatin)
When is the oral malignant melanoma vaccine meant to be given to a dog?
After OMM has developed
What is the MoA of the melanoma vaccine?
Antibody response against tyrosinase
What is the oral malignant melanoma size cut off for good prognosis?
<2cm
Dogs with oral malignant melanomas in what region of the mouth have a better prognosis?
Rostral oral cavity
Which dog breeds are predisposed to nasal tumors?
Dolichocephalics
Nasal tumors make up what % of respiratory tumors in dogs?
60-80%
What are the three most common clinical signs seen with nasal tumors in dogs?
Epistaxis, sneezing, nasal discharge
What is the most common nasal tumor in dogs?
Adenocarcinoma
What is the biologic behavior of most canine nasal tumors?
Locally aggressive, bony destruction, sinus/cribiform involvement
What % of canine nasal tumors have bilateral involvement?
80-90%
Why are radiographs less desirable for diagnosing canine nasal tumors even though they have similar sensitivity for detecting abnormalities as CT/MRI?
Less effective for staging disease
How do you definitively diagnose a canine nasal tumor?
Rhinoscopy and biopsy
What is the MST for canine nasal tumor with no treatment?
3mo
What type of nasal tumors respond to Piroxicam 50% of the time?
Carcinomas
What is the MST for canine nasal tumors treated with Piroxicam?
3mo
What is the MST for canine nasal tumors treated with surgery?
3mo
What is the treatment of choice for nasal tumors?
Radiation therapy
What is the MST for canine nasal tumors treated with radiation therapy?
12mo
What are side effects of radiation treatment of nasal tumors?
Hair loss (usually regrows), mucositis, dry nose
