Download MBBS Ophthalmology PPT 52 Retinoblastoma Lecture Notes

Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Ophthalmology PPT 52 Retinoblastoma Lecture Notes


The most common primary intraocular malignancy of


3% of all childhood cancers
The second most common malignant intraocular tumour
1 in 18,000 live births
25-30% cases are bilateral but asymmetric
Survival rates are over 95% in specialized centers but are

much lower in the developing world.
Genetics & Histopathology
RB1 is the tumour suppressor gene in which

mutations/deletion predisposes to retinoblastoma.

Tumours are composed of small basophilic cells (retinoblasts)

with large hyperchromatic nuclei and scanty cytoplasm.

Characterized by the formation of structures known as


Homer?Wright and fleurettes

Growth may be endophytic (into the vitreous) with seeding

of tumour cells throughout the eye, or

Exophytic (into the subretinal space) leading to retinal

detachment, or mixed, or the retina may be diffusely


Optic nerve invasion may occur, with spread of tumour along

the subarachnoid space to the brain.

Metastatic spread is to regional nodes, lung, brain and bone.

Flexner?Wintersteiner Rosettes

Endophytic growth

Optic nerve infiltration
Types of retinoblastoma

1. Heritable (hereditary, germline) retinoblastoma accounts for


One of the pair of alleles of RB1 is mutated in all the cells in the body.
When a further mutagenic event (`second hit' according to the `two-hit'

hypothesis proposed by Knudson) affects the second allele, the cell may

then undergo malignant transformation.

Because of the presence of the mutation in all cells, a large

majority of these children develop bilateral and multifocal


Pinealoblastoma (`trilateral retinoblastoma', which occurs in

up to 10%, usually before the age of 5),

Soft tissue sarcomas and melanomas
The risk of a second malignancy is about 6%
Increases five-fold if external beam
irradiation has been used to treat the original tumour,
The second tumour tends to arise within the irradiated field.

2. Non-heritable (non-hereditary, somatic) retinoblastoma.
60% Cases
The tumour is unilateral,
Non transmissible and
Does not predispose the patient to second non-ocular cancers.
If a patient has a solitary retinoblastoma and no positive

family history, Its very likely that

The risk in each sibling and the patient's offspring is about


Screening of at-risk family members.
Siblings at risk of retinoblastoma should be screened by
Prenatal ultrasonography,
Ophthalmoscopy soon after birth and
Then regularly until the age of 4 or 5 years.
Early diagnosis correlates with a higher chance of preserving

vision, salvaging the eye and preserving life.

If a child has heritable retinoblastoma, the risk to siblings is

2% if the parents are healthy, and 40% if a parent is affected.

Parents should also be screened

Clinical features
Bilateral cases present with in 1 yr of age
Unilateral cases present up to 2 yrs of age
Leukocoria (white pupillary reflex) is the commonest

presentation (60%) and may first be noticed in family



Strabismus is the second most common (20%); fundus

examination is therefore mandatory in all cases of childhood


Painful red eye with secondary glaucoma
Painful red eye with uveitis
Poor vision.
Inflammation or pseudoinflammation


Iris nodules with pseudohypopyon

Clinical features
Routine examination of a patient known to be at risk.

Orbital inflammation mimicking orbital or preseptal
cellulitis may occur with necrotic tumours

Orbital invasion or visible extraocular growth

Metastatic disease involving regional lymph nodes
and brain before the detection of ocular involvement is

Orbital cel ulitis

Orbital invasion

An intraretinal tumour

is a homogeneous,

dome-shaped white

lesion that becomes

irregular, often with

white flecks of


An endophytic tumour

projects into the

vitreous as a white mass

that may `seed' into the


An exophytic tumour

forms multilobular

subretinal white

masses and causes

overlying retinal

Clinical Stages
I. Quiescent stage.
II. Glaucomatous stage.
III. Stage of extraocular extension.
IV. Stage of distant metastasis.

Clinical Stages
I. Quiescent stage.
Lasts for about 6 months to1year.
Diminution of vision
Retinal detachment

Clinical Stages
II. Glaucomatous stage.
Pain, redness, watering.
Eyeball is enlarged leading to


Conjunctival congesion.
Corneal haze.
Increased intraocular pressure.
Rarely acute iridocyclitis.

Clinical Stages
III. Stage of extraocular


Fungation and involvement

of extraocular tissues

resulting in marked

Clinical Stages
IV. Stage of distant metastasis.
1. Lymphatic spread to preauricular and neighbouring lymph


2. Direct extension by continuity to the optic nerve and brain

is common.

3. Metastasis by blood stream involves cranial and other



Red reflex testing with a distant direct ophthalmoscope
Examination under anaesthesia
General examination
Measurement of the corneal diameter
Anterior chamber examination
Cycloplegic refraction.

Aqueous LDH levels
Wide field photography
CT scan
MRI for optic nerve evaluation
Bone scans and bone marrow aspiration
Genetic study

B Scan displays a

caulifiower like mass

arising from the retina.

A scan through the mass

shows a characteristic V-Y



Differential diagnosis
Persistent anterior fetal vasculature (persistent

hyperplastic primary vitreous)

Coats disease
Retinopathy of prematurity
Vitreoretinal dysplasia
1. Tumour destructive therapy.
When tumour is involving less than half of retina and optic

nerve is not involved

Chemoreduction followed by local therapy
(Cryotherapy, thermochemotherapy or brachytherapy) for

large tumours (>12mm in diameter)

Tumour <12 mm in diameter and <8mm in thickness

Radiotherapy (external beam radiotherapy or brachytherapy)

combined with chemotherapy is recommended for medium


Cryotherapy is indicated for a small tumour (<4.5 mm

indiameter and <2.5 mm in thickness) located anterior to

Laser photocoagulation is used for a small tumour located

posterior to equator <3 mm from fovea.

Thermotherapy with diode laser is used for a small tumour

located posterior to equator away from macula

2. Enucleation
Tumour involves more than half of the retina.
Optic nerve is involved.
Glaucoma is present and anterior chamber is involved.
Followed by radiotherapy and chemotherapy if optic nerve is


Intravenous carboplatin, etoposide and vincristine (CEV) are

given in three to six cycles according to the grade of

Careful review at frequent intervals is generally required

following treatment, in order to detect recurrence or the

development of a new tumour, particularly in heritable


Palliative therapy
Retinoblastoma with orbital extension,
Retinoblastoma with intracranial extension, and
Retinoblastoma with distant metastasis.

Surgical debulking of the orbit or orbital exentration, and
External beam radiotherapy
If untreated the prognosis is almost always bad and the

patient invariably dies.

Rarely, spontaneous regression with resultant cure and
shrinkage of the eyeball may occur due to necrosis followed

by calcification

Prognosis is fair (survival rate 70-85%) if the eyeball is

enucleated before the occurrence of extraocular extension.

1. Gene Rb1 responsible for retinoblastoma is located at:
A. 13q14
B. 14q13
C. 13p14
D. 14p13
2. Pathognomic feature of retinoblastoma is:
A. Necrosis
B. Calcification
C. Granulomatous reaction
D. None

3. Characteristic histopathological feature of retinoblastoma is:
A. Flexner?Wintersteiner rosettes,
B. Granulomatous reaction
C. Homer?Wright and fleurettes
D. None
4. On A scan characteristic pattern of Retinoblastoma is:
A. Collar stud appearance
B. V-Y Pattern
C. Cauliflower pattern
D. All

5. The most common clinical presentation of retinoblastoma is:
A. Nystagmus
B. Leukocoria
C. Strabismus
D. Secondary glaucoma
6. Which not a clinical presentation of Retinoblastoma
A. Nystagmus
B. Leukocoria
C. Strabismus
D. Growth retardation

7. Which not a differential diagnosis for Retinoblastoma
A. Coat's disease
B. Persistent hyperplastic primary vitreous
C. Endophthalmitis
D. Central retinal vein occlusion
8. Leucocoria is seen in:
A. Cataract
B. Coat's disease
C. Retinopathy of prematurity
D. All

9. If retinoblastoma involves more than half of the retina, the

treatment of choice is:

A. Chemotherapy
B. External beam radiotherapy
C. Enuclaetion
D. Cryotherapy
10. The most preferred combination of chemotherapy for

retinoblastoma is:

A. Methotrexate, etoposide & vinblastin
B. Methotrexate, etoposide & vincristin
C. Carboplatin, etoposide & vinblastin
D. Carboplatin, etoposide & vincritin

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This post was last modified on 07 April 2022