1-16 Intraocular Tumours Flashcards
Describe iris freckle
- What is it?
- Appearance?
- Dangers?
Areas of brown pigmentation on iris
- Melanocytes produce too much melanin at one spot
- Small, flat, discrete, multifocal, and bilateral
- Common, benign, no malignant potential.
Describe Iris Naevus
- What is it?
- Appearance?
- Dangers/effects?
“moles”
- Higher melanocyte count
- Circumscribed solitary flatish pigmented lesion (<3mm diameter, <1mm height)
- Can disrupt iris architecture to cause corectopia (irregular pupil shape) or ectropion uveae (IPE pulled over across pupil margin to ant. iris stroma)
- Benign, low malignant potential (recommend followup)
Describe iris melanocytoma
- What is it?
- Apart from iris, where else can it be?
- Appearance?
- Dangers/effects?
Magnocellular neavus of iris
- Iris naevus but also high melanin content
- Anywhere where melanocytes are found e.g. uveal tract, sclera, ONH (mostly)…
- Unilateral large jet-black lesions w/ “mossy” surface
- Congenital, benign neoplasm. Small risk of malignancy.
- Otherwise, can have secondary effects like obscuring angle.
Describe iris melanoma
- What is it?
- Usual origin?
- Appearance?
- Dangers?
“Cancer”. Unregulated proliferation of melanocytes
- Malignant iris neoplasm made of atypical melanocytes.
- Usually from pre-existing neavus
- Usually solitary nodule, usually inferior and atleast 3mm diameter + 1mm thick. Usually pigmented, but can be unpigmented. Can have diffuse appearance.
- Rare but most common primary iris neoplasm. Metastasis possible.
Describe ciliary body melanoma
- What is it?
- Appearance?
- Dangers/effects?
Malignant CB neoplasm
- Same pathogenesis of iris melanoma (unregulated proliferation)
- Sentinel vessels can be associated w/ it where vessels are dilated to nourish tumour
- Often associated w/ choroidal or iris melanoma due to proximity
- Growth -> astig, lens subluxation/dislocation, cataract
- Poor prognosis, fast metastasis. 30 – 50% mortality rate by 10 years. Due to high vascularisation, asymptomatic presentation at early stages, and requiring gonioscopy to diagnose.
Describe choroidal naevus
- What is it?
- Appearance?
- Dangers?
Benign melanocytic tumour of choroid
- Proliferation of melanocyte
- Usually round, green-grey, mostly flat (<5mm diameter + =<1mm thick).
- Detectable borders but hard to define.
- Overlying surface drusen possible.
- Congenital, max growth in childhood
- Very small malignancy potential.
Describe choroidal melanoma
Most common primary intraocular malignancy
- Same pathogenesis of other melanomas
- Elevated subretinal mass w/ variable appearance
– S, M, L thicknesses
– Dome, mushroom, or diffuse appearance (75, 20, 5%)
– Pigmented, non-pigmented, mixed (55, 15, 30%)
– Overlying lupofuscin is common
- 50% mortatlity at 10 yrs
Difference between drusen and lipofuscin?
Drusen and lipofuscin are both byproducts of RPE phagocytosis. Lipofuscin is created first and when inflammation occurs, drusen forms.
Lipofuscin = FIne orange granules
Drusen = Yellowy
Choroidal naevus is chronic so drusen is able to form after low-grade attaction of inflammation. Choroidal melanoma is acute so drusen has been made yet.
How to identify an ocular melanoma?
To Find Small Ocular Melanoma (TFSOM)
T = Thickness (>2mm)
F = Fluid (subretinal fluid presence)
S = Symptoms
O = Orange pigment (lipofuscin)
M = Margin (<3mm of ONH)
Most common ocular melanoma is…
- Risk factors?
- Dangers?
Uveal melanoma
Risk factors:
- Light iris + skin colour
- Pre-existing ocular neavus/melanocytosis
- UV?
Metastasis common w/ low around 8% survival rate past 2 years, average life of 13 more months.
Metastatic carcinomas often land where?
- Appearance?
- Dangers?
Choroid due to large blood supply.
- Even more common than primary choriodal tumours
- Primary sites include breast carcinoma in women and bronchial carcinoma in men.
- Fast-growing, cream-white lesions w/ indistinct margins
- 8 – 12 months life expectancy
Describe optic disc melanocytoma
- What is it?
- Appearance?
Magnocellular naevus of optic nerve
- Rare, very pigmented, benign tumour
- Lots of melanocytes, lots of melanin production
- Unilateral large jet-black lesions w/ feathery edges, often inferior part of ONH
Describe astrocytic hamartoma
- What is it?
- Appearance?
Astrocytoma of the retina/ONH (hamartoma = normal tissue that has proliferated a lot)
- Rare benign glial (astrocyte from RGC) cell tumour
- Yellowish/white semi-transparent lesion. Either nodule or relatively flat, often calcified centre
- Can be multiple + bilateral
Describe retinoblastoma?
- What is it?
- Pathogenesis?
- Clinical appearance?
Malignant neuroblastic (neuro stem cells) tumour
- RB1 gene mutation
- Primitive retinal cells become malignant before transformation (originate from INL)
- Most common childhood primary intraocular malignancy
- 30 – 40% is heritable
- Dome shaped, homogenously white retinal mass w/ irregular borders.
- Associated w/ prominent vascularization + white flecks
Either: - Endophytic = grow anterior into vitreous -> secondary glaucoma + inflammation
- Exophytic = Grow posteriorly -> serous RD
Otherwise, seen as - Leukocoria (white pupil reflex). Red reflex screening for newborns can detect this.
- Strabismus
Describe typical CHRPE
- What is it?
- Appearance?
- Dangers?
Congenital hypertrophy of RPE
- Large size + higher count of normal RPE cells
High density of large round melanosomes
- Unilateral, flat, dark grey/black round lesions w/ well defined margins.
- 1 – 3 DD size
- Solitary or grouped (“bear-tracks”)
- No lipofuscin granules (since RPE can’t phagocytose well)
- Benign, no malignant potential
