Retinoblastoma

Question 1

What is retinoblastoma?

Answer 1

Malignant tumor of embryonic neural retina.

Question 2

Age range for RtB?

Answer 2

<5 years

Question 3

Pathophysiology of RtB?

Answer 3

Intraocular growth, prior to invasion of structures within the globe or spread to metastatic sites.

Question 4

Symptoms of RtB?

Answer 4

Decreased visual acuity
Inflammation

Question 5

Signs of RtB?

Answer 5

Leukocoria
Strabismus
Hyphema
Virtreous hemorrhage- black pupil
Proptosis

Question 6

How do you classify RtB?

Answer 6

1. laterality: unilateral( 2 yrs)
   Bilateral (1 year)
   Trilateral ( <5 years)
2. Focality: Unifocal / multifocal
3. Genetics: hereditary - 40%
   non hereditary - 60%

Question 7

What is trilateral RtB?

Answer 7

Consists of bilateral hereditary + intracranial neuroblastic tumor of the pineal gland
Occurs in 5- 15 % of children with familial, multifocal or bilateral RtB.

Question 8

How do I diagnose RtB?

Answer 8

Elicit red relex
Siblings of patients should be screened at regular interval at least through age 3
Siblings of patients should be screened for mutations in RB1 genetic
CT or MRI of brain and orbit
No surgical biopsy is performed

Question 9

How do I investigate?

Answer 9

FBC
BUE and Creatinine
Lumbar puncture if there’s suspicion of CNS disease
Bone marrow biopsy in abnormal blood counts
Histopathologic evaluation if enucleation is performed.

Question 10

Treatment modalities?

Answer 10

Systemic chemotherapy
External beam radiotherapy
Local ophthalmic therapy ( laser Ry)
Intra arterial chemotherapy, using and interventional neuro-radiology approach
Enucleation

Question 11

Secondary malignacies

Answer 11

Osteocarcoma
Soft tissue sarcomas
Melanoma
Leukemia
Lymphoma
Breast cancer