Ocular Flashcards
What is the most common eyelid tumour in cats?
SCC
What’s the most common malignant tumour of the canine conjunctiva?
melanoma
What are the most common tumours of the canine conjunctiva/ eyelid?
- sebaceous/ meibomian adenoma
- epithelioma
- papilloma
- melanoma
(the above accounts for 80%)
even if malignant, tend to be localized
What’s the most common tumour of the feline eyelid?
SCC
What’s the most common tumour of the3rd eyelid in the cat/dog?
adenocarcinoma
can spread to the lymph nodes and lungs
How important in resection margin for conjunctival MCT?
even if incomplete, it may not recur
How much eyelid can be surgically removed?
dogs: 1/4-1/3
cats: 1/4
don’t do electrosurgery due to excessive scarring
What’s the prognosis for canine primary eyelid tumours?
overall good
- metastasis is rare
- could recur (10-15%) –> esp for conjunctival melanoma, adenocarcinoma
What’s the prognosis for feline primary eyelid tumours?
they are mostly malignant so prognosis is not as good as the dog
What are some differentials for limbal melanoma?
conjunctival melanoma, invasive uveal melanoma, metastatic malenoma, staphyloma, or coloboma
What’s the prognosis of epibulbar melanoma?
good
typically benign and slow growing
surgery +/- beta irradiation = curative
enucleate if invading the globe
What are some features of malignancy for ocular melanoma?
MI >/= 4 per 10hpf, increased nuclear atypia
metastatic rate = 4%
How common in primary malignant melanoma of the eye in the dog?
majority of intraocular melanoma are benign (75%)
95% arise from the ciliary body
What’s ocular melanosis of Cairn Terriers?
it’s an autosomal dominate disease
thickening and pigmentation of the iris
release of pigmentation into the aqueous –> secondary glaucoma
What are some clinical signs of primary ocular tumours?
hyphema
glaucomaWhat
How to treat primary ocular tumours?
- monitor
- consider removal of the tumour (surgery or laser) if causing issues
- don’t need to enucleate right away
What’s the prognosis of primary ocular tumours?
Historical data:
metastatic rate of 25% within 3m of enucleation and MST of 6m (malignant melanoma)
More recent data:
likely better than that.
Enucleation (early on) = curative
even if some black tissues are left behind it won’t grow
What’s the most common tumour of the feline anterior uvea?
melanoma
What’s the metastatic rate for feline malignant intraocular melanoma?
55-66%
lungs, liver
What are some features that will increase the metastatic rate of feline intraocular melanoma?
- increased MI >7/10 hpf
- necrosis
- extrascleral extension
- size
- choroid invasion
- increased E-cadherin or melan-A
(PLN-2 homozygosity DECREASES met rate)
malignant transformation possible – may take a long time, hard to predict
What’s the prognosis of feline diffuse iris melanoma?
Sx:
MST with ciliary body involvement = 5y
MST with sclera involvement as well = 1.5y
secondary glaucoma will decrease survival time
What are some tuours types for feline ocular post traumatic sarcoma?
spindle, round (LSA, CD79a positive), OSA/CSA
What’s the clinical behaviour of feline ocular post traumatic sarcoma?
can have latency up to 5 years
- tend to invade retina and optic nerve early on
- early enucleation improves prognosis
- recurrence = common as extra orbital invasion is common
What’s the outcome of feline ocular post traumatic sarcoma?
Survival is typically months once the eye is enucleated due to recurrence or local invasion
