Retinoblastoma is a type of eye cancer that begins in the retina, the light-sensitive part of the eye. It develops when cells within the retina called retinoblasts grow uncontrollably and form one or more tumours in the eye.

Types of retinoblastoma include:

• Heritable retinoblastoma – caused by a genetic mutation that is inherited or occurs in the womb. Heritable retinoblastoma usually affects both eyes and can result in multiple tumours
• Sporadic (non-heritable) retinoblastoma – develops when a gene mutation occurs in early childhood. Sporadic retinoblastoma is only ever associated with a single tumour in one eye

According to the Singapore Childhood Cancer Registry, retinoblastoma is the eighth most common childhood cancer in Singapore accounting for 3.2% of all cases and primarily occurs in children under the age of five years.

The most common sign of retinoblastoma is a cloudy white pupil or white glare upon shining a light into the eye, known as a white pupillary reflex or leukocoria. This is often visible in a flash photograph or during an eye exam.

Other symptoms of retinoblastoma in children or young adults include:

• Eyes that appear to look in different directions
• Redness of the white part of the eye
• Eye swelling or bulging
• Pupils that don’t get smaller when exposed to light
• Eye pain
• Vision issues