Eye Tumours: Retinoblastoma, Melanoma, Eyelid Cancer and Nevi

Tumours of the eye and its surrounding structures are uncommon, and many of those found are benign, such as freckles inside the eye or harmless eyelid lumps. A few, however, are cancers that need prompt diagnosis and specialised treatment. The good news is that several of the most important ones can be spotted early, sometimes in a family photograph or at a routine eye test, and that modern treatments increasingly save both life and the eye itself.

This guide covers the tumours people most often ask about: retinoblastoma in young children, uveal melanoma in adults, basal cell carcinoma and other eyelid cancers, and choroidal nevi, the common freckles at the back of the eye that need sensible monitoring rather than worry. It is intended to help you recognise warning signs and understand what specialists do; it cannot replace an examination.

Types of eye tumours at a glance

Eye tumours can arise in the eyelids, the surface of the eye (conjunctiva), inside the eye (intraocular) or in the eye socket (orbit). They can be benign or malignant, and malignant tumours can start in the eye (primary) or spread there from elsewhere (secondary or metastatic). In adults, metastases from cancers such as breast or lung cancer are actually the most common malignant tumours inside the eye.

Retinoblastoma: the white pupil in photos

Retinoblastoma is a cancer of the developing retina. It is the most common eye cancer in children, though still rare overall, and most cases are diagnosed before the age of five. It can affect one eye or both.

Signs parents may notice

• A white, yellowish or abnormal pupil reflex (leukocoria) – often noticed first in flash photographs, where one pupil looks white instead of the usual red, or in certain lighting. This is the most common presenting sign.
• A new squint – an eye that turns inward or outward. Any squint in a young child should be examined, partly for this reason. See our guide on strabismus and amblyopia.
• A red, painful or swollen eye without an obvious cause, or a change in the colour of the iris.
• Poor vision – the child may not follow objects with one eye.

Genetics

Retinoblastoma is caused by changes in both copies of the RB1 gene in retinal cells. In about 40 percent of children the condition is heritable: a change in RB1 is present in every cell of the body, either inherited from a parent or arising new in the child. These children more often have tumours in both eyes, may develop them at a younger age and have a higher lifelong risk of certain other cancers. Genetic testing and counselling are therefore offered to affected families, and siblings and children of survivors receive regular eye screening from birth.

Treatment and outlook

Treatment is carried out in specialist centres and depends on the size and spread of the tumour. Options include:

• Chemotherapy – given into a vein, directly into the eye's artery (intra-arterial) or into the eye (intravitreal).
• Focal treatments – laser therapy and cryotherapy (freezing) for small tumours.
• Plaque radiotherapy – a small radioactive disc stitched temporarily onto the eye.
• Enucleation – removal of the eye, when the tumour is large or vision cannot be saved. This can be life-saving, and children adapt remarkably well with an artificial eye.

In high-income countries, more than 95 percent of children with retinoblastoma survive. Survival is much lower in parts of the world where diagnosis is late, which is why awareness of the white pupil sign is so important.

Uveal melanoma

The uvea is the pigmented middle layer of the eye, made up of the iris, ciliary body and choroid. Melanoma arising here is the most common primary eye cancer in adults, though it remains rare. It is different from skin melanoma, with distinct genetic changes and behaviour. Risk is higher in people with fair skin, light-coloured eyes, an inability to tan, certain pigmented conditions of the eye (ocular melanocytosis) and a rare inherited condition involving the BAP1 gene. Unlike eyelid cancers, the link with sunlight is not clear-cut for most uveal melanomas.

Symptoms

Many uveal melanomas cause no symptoms and are detected during a routine dilated eye examination. When symptoms occur, they can include:

• Blurred or distorted vision.
• Flashes of light or new floaters.
• A shadow or loss of part of the visual field.
• A growing dark spot on the iris or a change in pupil shape.

Diagnosis and treatment

Diagnosis is usually based on a specialist examination together with ultrasound scanning, retinal photography, OCT and sometimes angiography; biopsy is used selectively, including to obtain genetic information that helps predict the risk of spread. Treatment aims to control the tumour while preserving the eye and useful vision where possible:

• Plaque brachytherapy – the most common eye-preserving treatment for small and medium tumours.
• Proton beam radiotherapy – precise external radiation, often used for tumours near the optic nerve or larger ones.
• Local resection or laser treatments in selected cases.
• Enucleation – for large tumours or when the eye cannot be saved.

The landmark Collaborative Ocular Melanoma Study (COMS) showed that for medium-sized choroidal melanomas, survival after plaque brachytherapy was similar to survival after removal of the eye, which supported the shift to eye-preserving treatment. Because uveal melanoma can spread, most often to the liver, sometimes years later, patients have regular long-term surveillance, often including liver imaging. Treatment for metastatic disease has advanced, including an approved immunotherapy for some patients, and clinical trials are ongoing.

Eyelid basal cell carcinoma and other eyelid cancers

The eyelids have thin skin that receives a lot of sun, so skin cancers are relatively common here. Basal cell carcinoma (BCC) accounts for the large majority of malignant eyelid tumours. It most often affects the lower lid and the inner corner of the eye in older adults with a history of sun exposure.

What to look for

• A small, firm, pearly or shiny lump, sometimes with tiny visible blood vessels.
• A lump with a central dip or ulcer that bleeds, crusts and does not heal.
• Loss of eyelashes over a lump, or distortion of the lid margin.
• A flat, scar-like or slowly spreading patch.

BCC grows slowly and very rarely spreads to distant organs, but if neglected it can invade deeply into the eye socket, sinuses or brain, especially at the inner corner. Treatment is usually surgical removal with careful checking of the margins, sometimes using Mohs micrographic surgery, followed by eyelid reconstruction by an oculoplastic surgeon. Other treatments, such as radiotherapy or targeted medicines, are reserved for particular situations.

Less common but more aggressive eyelid cancers include squamous cell carcinoma, sebaceous gland carcinoma (which can mimic a recurrent chalazion or one-sided chronic blepharitis) and Merkel cell carcinoma. Any lid lump that keeps coming back in the same place, or one-sided inflammation that does not respond to treatment, should be reviewed and possibly biopsied. Most lid lumps, of course, are benign: see our guide on styes and chalazia.

Choroidal nevus: a freckle at the back of the eye

A choroidal nevus is a flat or slightly raised, usually grey-brown spot in the choroid, made of pigment cells. It is essentially a freckle inside the eye. Nevi are common, found in a significant minority of adults, especially those with lighter skin. Almost all remain harmless for life, but a very small proportion can transform into melanoma, so they are documented and monitored.

How monitoring works

When an optometrist or ophthalmologist finds a nevus, they will usually photograph it and may perform OCT, ultrasound or autofluorescence imaging. Specialists look for features that increase the risk of growth, remembered with mnemonics such as TFSOM-UHHD ("To Find Small Ocular Melanoma Using Helpful Hints Daily"):

• Thickness greater than about 2 mm.
• Fluid under the retina.
• Symptoms such as blurred vision or flashes.
• Orange pigment (lipofuscin) on the surface.
• Margin close to the optic disc.
• Ultrasound hollowness.
• Absence of a surrounding halo.
• Absence of drusen (which suggest a long-standing, stable lesion).

A nevus with none of these features is generally rechecked by your optometrist or doctor at intervals, often every 6 to 12 months initially and then yearly if stable. Lesions with risk features are referred to an ocular oncology specialist. Keeping copies of your retinal photos and attending reviews is the most useful thing you can do. If you have never had a dilated examination, our article on how often to get an eye exam explains recommended intervals.

Prevention and early detection

• Have regular comprehensive eye examinations, including a look at the back of the eye. See our guide to eye examinations.
• Protect skin and eyes from UV light, especially if you are fair-skinned or spend long periods outdoors.
• Check flash photos of young children; if one pupil looks different, arrange an examination.
• Ensure babies and young children receive the vision checks offered in your country.
• If retinoblastoma runs in your family, ask about genetic counselling and screening for newborns.
• Never ignore an eyelid lump that bleeds, ulcerates, grows or causes loss of lashes.

When to see a doctor: warning signs

Most eye lumps and spots turn out to be harmless. But eye tumours are one area where acting quickly on a small sign makes a real difference, so if in doubt, get it checked.