ppt

1. Dr Meseret
Lectures for medical students
RETINOBLASTOMA

2. A malignant tumor that arises from immature pluripotent immature retinal
cells
Most coomon intraocular malignancy
Unliateral /bilateral
Unilateral (70%) or bilateral (30%).
Sporadic (94%) or familial (6%).
Non hereditary (60%) or hereditary (40%)
INTRODUCTION

3. Median age of onset
 Unilateral: 2 years, 80% cases are below 3 to 4 years.
Bilateral: < 12 months.
Incidence –1 in 15,000-20,000 live births
No racial or gender predeliction.
EPIDEMILOGY

4. RB represents a prototypical model demonstrating genetic etiology of cancer.
It is caused by mutation of the RB gene, a TSG on long arm of chromosome
13.
Normal individual inherits two copies of this gene one from each parent.
ALFRED KNUDSON’S TWO HIT HYPOTHESIS (1971)
Two separate loss of function mutations are required to inactivate both the
homologous loci of the RB gene for malignant phenotype to be expressed
GENETICS OF RB

5. 1. endophytic
-tumor growing from retina towards
vitreous and anterior structures
2. Exophytic
Tumor growing from retina towards
the choroid and extraocular
structures
3. Diffuse Infiltrative
No mass but only sgins of
endophthalmitis
4. Mixed (most common)
PATTERNS OF TUMOR GROWTH

6. TUMOR SPREAD

7. • Leukocoria - 60% • Strabismus - 20% • Secondary glaucoma
• Anterior segment invasion • Orbital inflammation • Orbital invasion
Presentations of retinoblastoma

8. Poor Prognostic Factors in Retinoblastoma
1. Optic nerve involvement
2. Choroidal invasion
3. Large tumour
4. Anterior location
5. Poor cellular differentiation
6. Older children

9. 1. Save life
2. Save globe
3. Save vision
4. Minimize complications
GOALS OF TREATMENT

10. Treatment Options of Retinoblastoma
1. Small tumours
• Laser photocoagulation
• Transpupillary thermotherapy
• Cryotherapy
2. Medium tumours
• Brachytherapy
• Chemotherapy
• External beam radiotherapy
3. Large tumours
• Chemotherapy followed by local treatment
• Enucleation
4. Extraocular extension
• External beam radiotherapy
5. Metastatic disease
• Chemotherapy

11. Differential diagnosis of leukocoria
Congenital cataract
Unilateral or bilateral Unilateral
Inflammatory cyclitic
membrane
Persistent hyperplastic
primary vitreous
Unilateral or bilateral
Coats disease
Unilateral Unilateral
Advanced retinopathy
of prematurity
Posterior pole toxocara
granuloma
Always bilateral but
may be asymmetrical

12. All children with suspected problem of Retinoblastoma need to be
referred to an ophthalmologist
NOTE