Eye cancer in children: the signs, the numbers and the ten-second check

I want to start with the sentence most articles about childhood cancer save for the end: your child almost certainly does not have this. Eye cancer in children is rare, and the point of this page is not to add one more fear to the list that comes free with every baby. The point is that the most treatable version of this story is the one where a parent noticed something small and acted on it inside a week or two, and in my clinic the parent who does that is almost never the one who read the most frightening article. It is the one who knew exactly what to look for, checked, and got on with dinner.

How common is eye cancer in children?

Rare enough that most family doctors will meet it only a handful of times in a career. Retinoblastoma, the most common eye cancer in childhood, affects about 6,000 children worldwide each year, roughly 300 to 400 of them in the USA and Canada, and almost all of them under five years old. It can affect one eye or both. Set against everything else this journal covers, the watery eyes and the styes and the endless conjunctivitis, it is a genuinely small number.

So why write about it at all? Because it is the one rare thing whose most famous early sign hides in an ordinary family photo album, and because the difference between finding it early and finding it late is measured in real outcomes, for the eye and for the child. Around 400,000 children and teenagers worldwide are diagnosed with some form of cancer every year, and the World Health Organization is blunt about the pattern: found early, cancer responds better to treatment, with a greater chance of survival and often less intensive treatment along the way. For the eye specifically, early is something parents are unusually well placed to deliver.

What are the signs of eye cancer in a child?

Six signs are worth knowing: a white glow in the pupil, a new squint, a change in iris colour, swelling of the eye, a red painful eye that does not settle, and a change in how your child seems to see. The glow is the one most parents have heard of, and I will come to it properly in a moment. The others deserve their own lines. A squint that appears out of nowhere, one eye drifting in or out where it never used to, deserves attention on its own terms, and not every turned eye is an illusion of baby face shapes. A change in the colour of the iris, so the two eyes no longer match. Swelling of the eye, or an eye that starts to look bigger than its partner. A red, painful eye that refuses to settle. And sometimes simply vision that seems to have changed, a child who starts holding things oddly close or stops making eye contact the way they did.

Here is the honest context for that list: every single item on it has innocent explanations that are far more common than cancer. New squints are usually just squints, which have their own treatment story. Red eyes are usually conjunctivitis. The list is not there so you can diagnose anything. It is there so that when one of these things appears, you book an appointment this week instead of filing it under wait and see.

What is the white glow in photos, and when does it matter?

A white, pale or cloudy glow in a pupil is called leukocoria, and the time it matters is when it keeps coming back in the same eye, across different photos and different lighting. A one-off glow in a single photo is usually nothing at all: the angle of the flash, or light catching the optic nerve head.

Here is what the camera is actually showing you. When a flash goes off, light travels into your child's eye and bounces back off the retina, and in a healthy eye that reflection comes back red or dark. Photographers have spent decades inventing settings to remove red-eye, and I have spent my career being pleased to see it, because a red reflex is a healthy retina announcing itself. A white glow means the light bounced back off something it should not have. I have written a whole article on the white glow and how to read it calmly, and if a photo has ever made you look twice, that page is where to go next.

What should I do if I think I see a sign?

Book an eye check within the week, and bring the photos. That is the whole plan, and both halves matter. Within the week, because the rare serious causes are exactly the ones where weeks matter, and because the far more likely outcome, reassurance, is worth having quickly instead of after a month of quiet dread. With the photos, because they are genuinely useful clinical information: in my clinic, three flash photos taken over months often tell me more than one look at a wriggling toddler.

What you should not do is start a home monitoring project, photographing the eye every night and comparing glows. I have watched kind, careful parents do this for six weeks before coming in, and the only thing it bought them was six bad weeks. A children's eye check is quick and gentle at any age, including in babies. The doctor will look at the red reflex with a simple light, and if anything needs a closer look, examine the back of the eye properly with drops. Most of these appointments end in a normal result and a shorter list of things to worry about.

How is retinoblastoma treated?

Treatment is planned around a strict order of priorities: the child first, then the eye, then as much vision as possible. Depending on the size and position of the tumour, the team may use freezing, heat or laser treatment aimed directly at it, chemotherapy given in several different ways, radiotherapy, or surgery to remove the eye when that is the safest road. When an eye is removed, it is replaced with an artificial eye made to match the other, and children adapt to this with a speed that surprises every parent who has sat in my clinic dreading it.

That single paragraph is deliberately short, because treatment is the part of this story that belongs to a specialist team sitting with your family, not to an article. What I most want parents to know about it is the part that comes after: children who finish treatment overwhelmingly go on with their childhoods, and I have written about what my own patients' lives look like now, because that half of the story is almost never told.

Do children survive eye cancer in Malaysia?

Yes, most do, and we no longer have to borrow other countries' numbers to say so. A 20-year study of 402 Malaysian children with retinoblastoma, drawn from the national eye database between 2004 and 2023, found survival of 96 in 100 at one year and more than 92 in 100 at five years. For cancer found in one eye, which is how most retinoblastoma presents, the five-year figure was 93 in 100.

The same study looked at what separated better outcomes from worse ones, and two factors stood out: how long the delay was before diagnosis, and whether families kept coming to follow-up. Read that list again, because it is quietly remarkable. The two things most strongly tied to survival in the Malaysian data are not treatments or technologies. They are a family noticing early and a family turning up. Both are in your hands, and neither requires anything more advanced than a phone and an appointment card.

Why is September a good month to check?

September is Childhood Cancer Awareness Month, marked around the world with a gold ribbon, gold because it is the colour of something precious. Hospitals light up, charities run campaigns, and for one month the rarest diagnoses in paediatrics get the attention their families live with all year.

For everyone else, I would keep participation simple. Tonight, open your camera roll. Find a few flash photos of your child, the ones where the eyes caught the light. Look at the pupils for ten seconds. Red or dark, close the phone and carry on with your evening, genuinely reassured. A white glow in the same eye more than once, or any sign from the list above, book a check this week and bring the photos. That is the whole ritual. It costs nothing, it needs no equipment, and it is the single most useful thing this awareness month can ask of a parent.

Common questions

References

1. World Health Organization · Childhood cancer fact sheet · www.who.int
2. Nor-Aizura Z et al. · Survival probabilities of retinoblastoma patients in Malaysia: a 20-year retrospective cohort study, Korean Journal of Ophthalmology (2026) · europepmc.org
3. National Cancer Institute · Retinoblastoma treatment (PDQ), patient version · www.cancer.gov
4. American Academy of Ophthalmology · What is retinoblastoma · www.aao.org
5. AAPOS · Retinoblastoma · aapos.org
6. NHS · Retinoblastoma, symptoms · www.nhs.uk

By Dr Chan Li Yen. General information only. It does not replace a consultation. If you are worried about your child's eyes or vision, please see an eye doctor.