Lecture 16 3/25/25 Flashcards
What are the general characteristics of oral tumors?
-make up 3 to 12% of all tumors in cats and dogs
-male dogs are 2.4x more likely to develop oral tumors than female dogs
What are the common presenting complaints in animals with oral tumors?
-halitosis
-dysphagia
-weight loss
-oral bleeding
-visualization of mass
What are the characteristics of physical exam when oral tumors are suspected?
-typically have to sedate/anesthetize to visualize masses
-may find concurrent periodontal disease
-enlarged submandibular and/or retropharyngeal LNs possible, especially with melanoma
-may find jaw asymmetry or pain around the mouth
Which diagnostics are done for oral tumors?
-dental rads to identify bone loss
-CT scans to determine extent of masses
-FNAs (rarely diagnostic)
-biopsy
What are the characteristics of oral melanoma?
-tumor of melanocytes
-most common oral tumor of dogs
-very rare in cats
-often pigmented, but can have amelanotic tumors
Which dog breeds are more likely to develop oral melanoma?
-cocker spaniel
-chow chow
-golden retriever
-small breed dogs
What are the characteristics of oral melanoma metastasis?
-highly metastatic, even if not initially apparent
-main sites of metastasis are lymph nodes and lungs
-40% of normal size lymph nodes have metastasis on cytology
What are the characteristics of surgery as a treatment for oral melanoma?
-surgery is gold standard
-must do a mandibulectomy/maxillectomy +/- lymphadenopathy
-most dogs handle very well with very good cosmetic results
-must warn owners about post-op cosmetics
-bleeding is largest risk
-dysphagia can occur but is typically temporary
How does oral melanoma respond to common therapies other than surgery?
-extremely sensitive to radiation, but with decreased survival times and increased potential for recurrence
-relatively resistant to chemotherapy
What are the characteristics of immunotherapy for oral melanoma?
-FDA approved vaccine is available for dogs
-unclear results regarding benefit
-PD-1 antibody gilvetmab has been approved and has a 70% response rate
-unknown long term outcomes with gilvetmab
What is the prognosis for oral melanoma?
-highly dependent on stage
-good prognosis with surgical removal of small masses (MST 2 years)
-moderate prognosis with surgical removal of larger masses or with LN mets (6-9 months)
-pulmonary nodules has poor prognosis (3 months)
-radiation therapy has moderate prognosis (4-12 months)
-short survival if no treatment pursued (2 months)
What are the general characteristics of oral squamous cell carcinoma?
-tumor of oral epithelium
-second most common oral tumor in dogs
-most common oral tumor in cats
-extremely lytic and invasive
-rarely metastatic unless tonsillar or caudal tongue in dogs
-goes to LNs and lungs when it does metastasize
What are the characteristics of oral squamous cell carcinoma in dogs?
-surgery is treatment of choice
-surgery often curative if margins can be obtained
-can use radiation by itself or after surgery
-some cases respond to chemo
What is the prognosis for canine oral squamous cell carcinoma?
-prognosis generally excellent with surgery +/- radiation (2 to 3 years) if no metastasis
-radiation alone can provide tumor control for around a year
-survival with chemo or NSAIDs alone is not well documented
What are the characteristics of feline oral squamous cell carcinoma?
-similar behavior to the canine version, but more aggressive
-commonly sublingual
-10 to 20% metastasis rate
-spreads to LNs and lungs
-treatment of choice is surgery, but not tolerated well by cats
-radiation can be used alone and cats can respond for short periods
-chemo has been used with limited success
What is the prognosis for feline oral squamous cell carcinoma?
-generally poor
-can survive 12 to 18 months with successful surgery
-radiation therapy provides 3 to 6 months of survival
-palladia provides 2 to 4 months of survival
-NSAIDs alone provide 2 months of survival
What are the characteristics of meloxicam use in cats?
-warning on label says drug can lead to AKI
-research shows drug is safe for use in CKD stage 2 and 3 cats
-does not reduce GFR when given to cats
-cats need NSAIDs for pain control; do not withodl
What are the characteristics of fibrosarcoma?
-tumor of fibroblasts
-golden retrievers are predisposed
-often called biologically high grade, histologically low grade
-can be misdiagnosed on histopath. with inadequate history; looks like scar tissue
What are the characteristics of fibrosarcoma treatment?
-surgery is treatment of choice, but requires wide margins
-radiation can be used after surgery if margins cannot be obtained or if used without surgery first
-chemo is ineffective
What are the characteristics of osteosarcoma?
-tumor of osteoblasts
-slight female predilection
-lower metastatic rate compared to appendicular OSA
-must biopsy to differentiate from multilobular tumor of bone
What are the characteristics of osteosarcoma treatment and prognosis?
-can survive 14 to 18 months with surgery if in mandible
-can survive 5 to 10 months with surgery if in maxilla
-can survive 9 months with radiation
-surgery is treatment of choice
-chemo is not definitively shown to help vs surgery alone
What are the characteristics of acanthomatous ameloblastoma?
-odontogenic tumor
-benign/has never metastasized
-very locally aggressive; requires aggressive therapy
What are the characteristics of treatment for acanthomatous ameloblastoma?
-surgery is curative in almost all cases if margins are clean (survival of 3 to 6 years)
-even narrow margins have a low recurrence rate
-tumors do respond to radiation
-intralesional bleomycin chemo has 100% response rate
What are the characteristics of peripheral odontogenic fibroma?
-most common non-cancerous oral mass
-benign mass caused by irritation of periodontal ligament
-does not invade underlying bone
-surgery is generally curative but most remove the tooth
-radiation is also effective
