Retinoblastoma

Clinical Description

Intraocular tumour in children. Can be unilateral, bilateral. Trilateral retinoblastoma is when there is also an intracranial neuroblastic tumour. It is Life-threatening

Signs and Symptoms

• This depends on the tumour size, its location on the retina, its growth pattern – endophytic, exophytic or infiltrative and its effect on visual functions.
• The most common are leukocoria (white reflect from the pupil) and exophthalmos (proptosis). Squint (eye misalignment), red eye, poor vision, vitreous haemorrhage, microphthalmos and orbital cellulitis, anterior scleral staphyloma, hyphaemia and buphthalmos were rare presentations.

Investigations

• The main diagnostic criteria are clinical and not histological confirmation before treatment. Enucleation, a standard mode of tissue collection for histopathology assessment is a treatment modality and it is the mainstay treatment modality in

Malawi.

• Clinical evaluation
• This should include a thorough family history, a complete physical examination which should include visual acuity (to assess macula involvement), the pupillary reflexes and extraocular movements (may point towards trilateral disease) and fundoscopy. Evidence of anterior segment involvement (iris neovascularization, hyphemia, or pseudo hypopyon) have a relative increased risk for metastatic disease.
• Assess for local and regional spread as well as other non-ocular tumours
• Imaging studies
• Intraocular calcifications in small children are pathognomonic of retinoblastoma.
• These may include ultrasonography, X-Rays, CT scan, and MRI. X Rays and CT scan pose risks for secondary tumours from radiation exposures.

Treatment

• Multifaceted and demands a multidisciplinary approach.
• The primary objective in treatment is to save life. Secondarily, efforts are made to save the globe and where possible salvage vision.
• Consider the following
• Counselling the guardians on treatment options and what to expect
• Screening of family members to establish whether the index patient may have germline or somatic disease.
• Genetic counseling of the parents, patient (if old enough) and siblings on the possibility of tumor development in future offspring and the need for early and regular ophthalmic examinations.
• Mainstay treatment for Retinoblastoma in Malawi is surgical
• For patients with presumed intraocular retinoblastoma, start with enucleation
• Always do an EUA in the other eye – in cases on uniocular retinoblastoma
• Intraoperatively always measure and document the length of the resected optic nerve, the thickness of the base and resection margin of the nerve, and any evidence of scleral, or extraocular muscle involvement.
• Always send the eyeball for histological assessment
• If any evidence of possible extraocular involvement eg tumour cells at the resection margins, consider chemotherapy – see below.
• For patients presenting with evidence of extraocular involvement (proptosis, orbital cellulitis etc)
• Consider chemotherapy – Vincristine, Carboplatin and Etoposide, every three week for up to three cycles and consider enucleation after three cycles.
• Follow up of patients
• This depends on the patient’s age
• For those below 3 years, review (conduct EUAs in the only eye and examine the socket) every three months until they are 3 years old.
• At 3 years or older, review every six months (do EUAs in the better eye and examine the socket) until the patient is 5 years old.
• Thereafter review yearly.