Retinoblastoma

Retinoblastoma is the most common intraocular tumor of childhood.

Clinical Manifestations

Leukocoria (60%)
Strabismus (20%)

Other - Uveitis, Orbital cellulitis, Hyphaema, Heterochromia, Glaucoma, Bupthalmos

Calcification is another feature of retinoblastomas, usually occurring in necrotic areas.
Calcium stains with H&E. It is worth identifying calcium in suspect eyes by ultrasound or CT scan to differentiate retinoblastomas from other tumors.

Management

Empirical Genetic Counselling
- Enucleation
  - Unilateral, poor visual prognosis
- Plaque
  - 4-12mm +/- vitreous seeding
- External Beam
  - 12mm, multiple foci, only eye
- Laser
  - Consider - indirect, xenon arc
  - Cryotherapy if <2dd in size
- Chemotherapy, if intracranial extension

Retinal Tumor

Retinoblastoma

Heritable (AD) or sporadic

Z 1- The most common primary intraocular malignant tumor in children, of which 90% are younger than 3 yrs
2- adult = childhood choroidal melanoma
3- extraocular/orbital malignant tumor most common in children rhabdomyosarcoma
4- most common extraocular vascular tumor in children capillary hemangioma
5- most common extraocular vascular tumor in adults cavernous hemangioma

Etiology

Parents are affected or gene carriers, or germ cell mutation
- Autosomal dominant 40%
Patient with retinoblast mutation
- Uninherited 60%
Patient with autosomal chromosome mutation
- RB, complicated with intelligence and growth retardation.

Study shows: Loss of or unactivated RB gene is the key factor of RB

Best INV: Ocular US - CT - MRI to finally confirm indicated treatment of excisionZ

Staging

Intraocular stage
Glaucomatous stage
Extraocular stage
Metastasis stage

Differential Diagnosis

	RB	Coats disease
Onset age	90%<3 yrs	>6-8 yrs
Eyes involved	30% both	95% single
Microcirculation abnormality	none	Diffuse microaneurysm
Cholesterol cystal	none	Subretinal, obvious
Calcification	+	-
B-us	Solid tumor	Without solid tumor

RB vs. Coats Disease

Treatment

Small tumor localized in central retina can be effectively treated with photocoagulation
Small tumor localized in peripheral retina can be treated with cryotherapy
Moderate localized tumor: Plaque radiation therapy
Big tumor: EnucleationZ ; removal of eye if large tumour
Extraocular stage: enucleation + chemotherapy + radiation (bad prognosis)
Metastasis: no specific treatment