Retinoblastoma is a very uncommon tumour of the retina (eye cancer) that develops in children (pediatric cancer).
The retina, or back of the eye, is affected, and it may affect one or both eyes. The retina helps you see by sending messages to the brain.
If detected early, there are treatments available that usually result in a satisfactory outcome. Preservation of usable eyesight and patient life are the goals of treatment for retinoblastoma.
It is advisable to consult with an experienced ophthalmologist for patient management, as they can offer the necessary support.
- Origin: Malignant tumour of the developing retina. Develops from immature cells of the retina.
- Cause: Inactivation of RB1 in the precursor of cone cells of developing retina.
- Age: Children <5 years of age.
- Unifocal/ multifocal
- 60% of cases: unilateral; mean age-24 months.
- 40% cases: bilateral retinoblastoma; mean age-15 months.
- Heritable retinoblastoma: a/w other non-ocular tumours.
Signs and symptoms:
Since retinoblastoma commonly occurs before a child learns to communicate or understand that his vision is blurred, the following signs may be suggestive:
- Leukocoria: most common and earliest symptom. Pupil of eyes appear white
- Trouble following movement
- Strabismus
- Pain: high irritability, fussiness, poor appetite or sleep quality might be indicative
- Buphthalmos
- Proptosis
- Hyphema
- Orbital cellulitis
Diagnosis:
- Fundus examination: indirect ophthalmoscopy.
- Imaging studies
- Family history of retinoblastoma
- Molecular genetic testing: heterogeneous germline pathogenic variant of RB1.
Staging:
- HX: Unknown/ insufficient evidence of heterogeneous germline pathogenic variant of RB1.
- H0. Did not inherit RB1
- H1. Bilateral retinoblastoma, trilateral retinoblastoma (retinoblastoma with intracranial CNS midline embryonic tumour), retinoblastoma with similar family history of retinoblastoma, or RB1 gene identified.
Management:
- Early diagnosis and treatment is crucial for survival
- Treatment options depend on stage, laterality, and extraocular extension.
- The following treatment options are used in various combinations:
- Enucleation
- Crayotherapy
- Laser
- Systemic or ocular chemotherapy
- Radiation therapy
Surveillance:
- RB1 gene positive children: Ocular examinations
- every 3-4 weeks till 6 months of age
- every 2 months till 3 years of age
- every 3-6 months till 7 years of age
- Yearly once till 10 years of age
- Every 2 years after 10 years of age.
- U/L retinoblastoma without RB1 gene mutation: Ocular examination and ocular USG
- every 3-6 weeks till 7 years of age
- Once every 2 years after 7 years of age
- Retinomas: Retinal examinations and imaging 1-2 years
- To detect non-ocular tumours: early of any signs and symptoms.
Prognosis:
- The overall survival rate: 95%
- Prognosis is better with early diagnosis.
- Loss of vision is less with diagnosis before 2 years of age
- Life-long surveillance is required for survivors.