What Is Retinoblastoma?
Retinoblastoma is a fast growing eye cancer affecting babies and young children. Tumours arise from immature cells of the retina, the light-sensitive layer of cells lining the inner wall of the eye, from the very back to the front where the white sclera meets the coloured ring of the iris. The retina converts light into nerve signals for transmission to the brain.
Retinoblastoma is a fast growing eye cancer affecting babies and young children. Tumours may form in one eye (unilateral) or both eyes (bilateral), and can spread outside the eye (extraocular retinoblastoma). Rarely, a separate tumour develops in the brain (trilateral retinoblastoma). This cancer typically develops before 3 years of age, and some children are born with tumours.
What Causes Retinoblastoma?
Errors (mutations) on the RB1 gene or MYCN gene cause tumours to form. These errors can be inherited from a parent, but most often occur spontaneously during the baby’s early development. Retinoblastoma is no one’s fault. It is not a curse and is not contagious.
How Common Is Retinoblastoma?
Retinoblastoma affects about 1 in 15,000 live births, and an estimated 9,000 children develop the cancer each year around the world. Due to global population distribution, 90% of children with retinoblastoma live in economically developing countries.
What are the Signs and Symptoms?
The most common early sign of retinoblastoma is leukocoria, a white glow in the pupil (black circle) of the affected eye, seen in flash photographs. This reflection may be visible to the naked eye in dim light when cancer fills the eye, or in very young babies. Other signs include a squint (misaligned eyes), red, painful or swollen eye. Trilateral retinoblastoma causes a range of symptoms, depending on its location in the brain.
How is Retinoblastoma Diagnosed?
Prompt referral to an eye doctor is vital when retinoblastoma is suspected, or when a child is known to be at risk because a parent or sibling had this cancer or a parent carries a known RB1 mutation. Referral to an ophthalmologist trained in the treatment of retinoblastoma is vital to ensure optimal care of the child and family.
When eye cancer is diagnosed, tests are done to learn more about the number, size and position of tumours, and whether cancer has spread outside the eye. This process is called staging and classification, and helps doctors decide which treatments are most appropriate.
How is Retinoblastoma Treated?
Treatment depends on the number, size and location of tumour(s), whether one or both eyes is involved, and whether cancer has escaped the eye or is at risk of spreading. Treatments include laser, cryotherapy (freezing), chemotherapy, brachytherapy (radioactive plaque), external beam radiotherapy and enucleation (surgical removal of the eye).
Prompt removal of the eye is standard treatment when only one eye is affected with advanced cancer, and is essential when there is a risk of cancer escaping the eye.
Extraocular and trilateral retinoblastoma require intensive chemotherapy for the best chance of cure. Bone marrow or stem cell transplant and radiotherapy may also be used.
What is the Prognosis?
More than 96% of children treated in developed countries survive, but many children lose at least one eye. Even when eyes are saved, most children have severe vision loss.
Without early treatment, retinoblastoma quickly spreads to the brain or bone marrow. Even with intensive treatments, the chance of cure is very small. Globally, 7,000 children die every year due to delayed diagnosis and inappropriate or incomplete treatment. .
When treatment has ended, children need close follow up care to check for new cancer growth and recurrence of treated tumours, especially after eye-salvage therapy. Children often respond very well to initial eye-salvage treatment, but relapse is common weeks or months later, with need for further treatment often extending over months or several years.
Without close monitoring, relapse is not detected early. This can cost the child their eye and their life.
Trilateral retinoblastoma is extremely difficult to treat, and most children die within 12-18 months of diagnosis. However, a slowly increasing number of survivors around the world is inspiring hope for children with this pernicious form of retinoblastoma.
Learn the Lingo
Understanding the language of retinoblastoma is vital. Parents will be better prepared to converse with medical professionals, to advocate, seek second opinions if needed, and support best possible care. Relatives and friends will more easily understand what is happening and be better able to support the family through treatment and follow up care.