SA Oropharyngeal Neoplasia (Ganjei)

Question 1

Most common neoplastic oropharyngeal lesions seen in dogs (5)

gingiva, tonsils, lips

Answer 1

Malignant melanoma
SCC
fibrosarcoma
osteosarcoma
acanthomatous ameloblastoma

majority are malignant! all = expected to recur if marginally excised

Question 2

Most common neoplastic oropharyngeal lesion seen in cats

gingiva, tongue

Answer 2

SCC (70-80%)

malignant!

most common non-neoplastic: eosinophilic granuloma

Question 3

Key points for obtaining a biopsy

Answer 3

1. Obtain living tissue
2. Consider tumor “seeding” (e.g., maxillary tumors: don’t go thru lip)

Tumor seeding or needle seeding refers to rare occurrences when the needle inserted into a tumor during a biopsy dislodges and spreads cancer cells.

Question 4

Two key components to predicting behavior of biopsied tumor

Answer 4

Stage & Grade

Question 5

Two common areas of the body to evaluate for metastases

Answer 5

• regional lymph nodes (mandibular and retropharyngeal)
• lungs

CT scan, x-rays; palpate & FNA (mandibular LN only)

Question 6

First line of treatment for oropharyngeal tumors

Answer 6

Surgery (excision)
- wide

pretty much all are expected to recur if marginally excised

radical excision = complete amputation or removal of muscle belly, jaw, etc. – not used in oropharyngeal tumors

Question 7

Maxillectomy

Answer 7

removing portion of maxillary arcade (or complete)

Question 8

Mandibulectomry

Answer 8

removing portion of mandible or complete)

Question 9

ID procedure

Answer 9

Glossectomy

Question 10

Local vs systemic tumor treatment

Answer 10

Question 11

General risks of oropharyngeal tumor surgeries

Answer 11

dehisence; tumor recurence

maxilla dehiscene –> oronasal fistula

Question 12

ID

Answer 12

Mandibulectomy –> destabilized mandible –> mandibular drift & malocclusion (lost of attachment)

Question 13

Why is infection not a risk post-oropharyngeal tumor surgery?

Answer 13

oral cavity has robust vascular supply

Question 14

Additional post-oropharyngeal tumor surgery risks in cats?

Answer 14

dysphagia/inappetance; difficulty grooming

need esopheal feeding tube

98% complication rate after mandibulectomy

Question 15

Different prognoses of non-tonsillar SCC in dogs based on tumor location:

Answer 15

non-tonsillar:
- rostral = good
- caudal = poor

20% metastases; 0-50% recurrence

Question 16

Prognosis of tonsillar SCC in dogs

Answer 16

HIGHLY METASTATIC! (63-98%)
Mean Survival Time = 2 months, < 10% survival after 1 year

Question 17

Prognosis of SCC in cats

Answer 17

• Highly metastatic!!
• MST w/ wide excision = 45d
• MST w/ radiation = 90d, but poorly responsive
• < 10% mean survival after 1 year

MST = Mean Survival Time

Question 18

Fibrosarcoma prognosis in dogs vs. cats

Answer 18

DOGS
- Does not metastasize often
- wide excision: MST = 10-12m, high local recurrence
- radiation: MST = 7-26m, 1-yr survival 76%

CATS
- rarely metastasizes
- fair prognosis when wide excision is elected

Question 19

“High-Lo” entity meaning in fibrosarcomas in dogs

Answer 19

Look low-grade histologically, but are actually high-grade biologically

Question 20

Prognosis of Acanthomatous Ameloblastoma

Answer 20

No metastasis :)
Excellent prognosis with wide excision