Oncology Flashcards
Apocrine gland carcinoma px
1-2yrs if mass and LN excisions (and no adjunct treatment)
Highly malignant and metastatic potential
Perianal adenoma px
Good - commonly benign
Surgical margins required for a MCT
> 3cms + deep fascial plane
+ chemo/radiation
Soft tissue sarcoma behaviour
locally invasive - slow to met but will
may need radical excision ie. amputation
melanoma tx options
sx excision + vaccine + chemo
FNA limitations
- fibrous/sarcomas do not exfoliate well
- cannot rule anything out - can only rule in
- cannot grade neoplasia
A mass you suspect is malignant would you rather a excision or incisional biopsy?
- incisional (but do not extend margins!!)
- excisional makes potential re-resection difficult
what dog breed is associated with apocrine gland carcinomas?
cocker spaniels
why is minimal manipulation of the tumour important?
to prevent exfoliate of tumour cells + to not stimulate release of cytokines (MCT - histamine)
give an example of a biologic margin
fascia, tendon, cartilage
– collagen rich, low vascularity = natural barrier
what is a marginal excision?
en bloc removal of a tumour and pseudocapsule ‘shell out’ – for benign tumours (lipomas)
what is considered a wide margin?
> 3cm
what is considered a narrow margin?
<2-3cm
what tumour types require wide excision?
- plasmacytoma
- mast cell tumour (G1-2)
- cutaneous melanoma
’ well contained malignant disease’
which tumour types require radical excision?
infiltrative, highly malignant disease
always submit excised tissue for histologic examination –> surgical site marking
Why?
to confirm the diagnosis and confirm complete excision (good margins)
what are your options when you receive histo report that you have ‘dirty margins’?
- Revisit surgical options: en bloc excision/radical excision of previous site
- Adjunctive therapy - radiation/chemo
a digital melanoma is more likely to be malignant or benign?
malignant
what advise would you give an owner of a dog with perianal adenoma?
It is very commonly benign.
The malignant form is an adenocarcinoma and associated with hypercalcaemia.
Recommend - Biochem to assess calcium levels
+ surgical exicison
+ castration
Ddx for non-neoplastic oral masses
- gingival hyperplasia
- eosinophilic granuloma complex
- osteomyelitis
- lymphocytic plasmacytic stomatitis
- nasopharyngeal polyps
- salivary mucoceles
Malignant canine oral neoplasias
- malignant melanoma
- SCC
- fibrosarcoma
- osteosarcoma
benign canine neoplasias
periodontal ligament tumours (odontogenic/epulides)
Feline malignant oral neoplasias
SCC
signalment canine oral malignant melanoma
older, male dogs w/ heavily pigmented mucosa
behaviour of oral malignant melanoma
- firm, vascular, rapidly growing mass –> bone invasion and dental disruption common
- early mets to LNs and lungs
- poor prognosis
+often necrosis + infection
signalment canine oral SCC
older large breed dogs
how does location affect behaviour of oral SCC?
- Rostral = locally invasive, low mets
- Caudal = invasive, high mets
- Tonsils = aggressive, high mets
- Lingual = aggressive
appearance of oral SCC
red, friable, ulcerated +/- dental disruption and bony invasion
prognosis of cat w/ sublingual SCC
grave (along w/ maxilla)
prognosis of cat w/ mandibular SCC
fair prognosis w/ excision
oral fibrosarcoma signalment
young dogs OR older 7-8yo large breed dogs
OR older cats
appearance of oral fibrosarcoma
pink/red, firm, fixed, multilobulated, smooth
behaviour of oral fibrosarcomas
- locally invasive
- distant mets uncommon
signalment of oral osteosarcomas
large breed dogs
behaviour of oral osteosarcomas
- distant mets
- locally invasive
- -> poor prognosis
appearance and behaviour of ameloblastomas/acanthomatous epulis
- gingiva and mucosa of tooth-bearing surface in medium to large breed dogs
- benign
- bony lysis/proliferation, alveolar bone resorption and tooth displacement
appearance and behaviour of peripheral odontogenic fibromas
- pendunculated, firm, smooth, pink
- benign, slow growing
- broader base
- various amounts of calcification w/in mass (ossifying epulis)
appearance and behaviour of odontomas
- sharply defined mass of calcified material surrounded by narrow radiolucent band + variable tooth-like structures
- benign
treatment of dentigerous cysts
- cyst w/ tooth/teeth embedded in wall –> surgical removal of the unerupted tooth and removal of cyst lining
what is a feline inductive odontogenic tumour?
seen in young cats <18mo, on rostral maxilla locally invasive fibroameloblastoma - no mets
Tongue neoplasia ddx
SCC
others: malignant melanoma, fibrosarcoma, plasmacytoma, haemangiosarcoma
gross margin for oral neoplasia resection
1cm - maintain oral function and minimise deformity
Resection of what % of the body of the tongue is well tolerated?
40-60%
Complications of maxillectomies
mandibular canine teeth –> ulceration on lips
complications of mandibulectomies
- mandibular drift
- mandibular instability, difficulty prehending food
- ranula
