There are several types of eye cancer, including melanoma, lymphoma, and retinoblastoma; all are rare. Eye cancer that starts in the eye is known as primary cancer. Cancer that spreads to the eye from elsewhere in the body is secondary cancer.
Treatment options for eye cancer include radiotherapy, chemotherapy and surgery. The prognosis for eye cancer depends on how early it is diagnosed and treated. Symptoms of eye cancer aren't always obvious, and it may be detected during an eye test. That's one reason regular eye tests are important for everyone.
See your GP or optician if you notice vision changes, a lump in or behind your eye or eyelid that gets bigger, or eye pain. Eye cancer is rare, and symptoms may be similar to those of other eye conditions, but it's always best to get them checked.
What is eye cancer?
Cancer happens when abnormal changes happen to cells in the body, and these abnormal cells divide and grow. Eye cancer is also known as ocular cancer, the term for several kinds of cancer that can develop in or around the eye. Eye cancer inside the eye is called intraocular cancer. Cancer around the eye is called extraocular cancer.
Signs and symptoms of eye cancer
Eye cancer can begin without causing noticeable symptoms. Sometimes it's first detected at a routine eye test. The NHS recommends everyone should have an eye test at least every two years. If you notice changes to your vision or eyes, an eye test can check for the many other eye conditions that cause symptoms similar to eye cancer. An optician can refer you to a specialist eye doctor (ophthalmologist) if they suspect you have eye cancer.
Potential signs and symptoms of eye cancer include vision changes such as:
- Seeing flashes of light
- Shadows across your vision
- Blurry vision
- Full or partial vision loss
- Loss of peripheral vision (side vision)
Signs of eye cancer can also include physical and visible changes to the eye, including:
- A lump on, or in, your eyelid that's getting bigger
- A bulging eye
- A change in how the eye looks, such as a dark spot on the iris
- Rarely, eye pain, which can be caused by high eye pressure
- Irritated eyes, chronic conjunctivitis
- A cataract in the affected eye
It's always best to see your optician if you notice any changes or are concerned. Opticians can diagnose a range of common eye conditions and refer you to a specialist if they suspect you may have eye cancer.
Types of eye cancer
There are several types of eye cancer, according to the type of cell affected. All eye cancers are rare, but the most common is uveal melanoma.
What are the causes of eye cancer?
Eye cancer is rare, and generally, the older you are, the greater the risk. An exception is retinoblastoma which occurs in very young children. The risk factors for different types of eye cancer can vary.
The following risk factors play a role in several types of eye cancer:
- Excessive exposure to ultraviolet light, for example, from sunbeds.
- Age: nearly one in four people diagnosed with eye cancer are over 75 (Source: Cancer Research UK).
- A mutation in the BAP1 gene can increase the risk of developing a range of cancers.
For eye melanoma, the risk factors include:
- Light eye colour: people with blue, green, and grey eyes are more at risk of eye melanoma than people with dark coloured eyes.
- Irregular moles: people with irregular moles are more likely to develop skin cancer and eye melanoma.
For squamous cell cancer, the risk factors include:
- Taking medicines that suppress the immune system, for example, after an organ transplant.
- Having an HIV or HPV infection.
For eye lymphoma, the risk factors include:
- Weakened immune system, for example, through autoimmune disease, HIV or AIDS, or taking medication to stop organ transplant rejection.
For retinoblastoma, the risk factors include:
- Age: it's most common in very young children as it affects cells in the developing retina.
- Genetics: around four in 10 cases of retinoblastoma are due to an inheritable gene defect.
How to detect eye cancer
Sometimes eye cancer is found during a routine eye exam at the opticians. If your optician or GP suspects you may have eye cancer, they will refer you to an ophthalmologist, a specialist eye doctor.
Ophthalmologists use various tests to diagnose eye cancer. Some tests help determine the stage of your cancer to help your healthcare team plan appropriate treatment. Tests can include:
- Ultrasound, which uses sound waves to create images of the eye and around it.
- Fluorescein angiogram in which a special dye is injected into the bloodstream. This shows in the eye, allowing more detailed images.
- Magnetic resonance imaging (MRI) scan which uses magnetism to create detailed images.
- A blood test to allow genetic testing.
- Occasionally, a lumbar puncture to check for cancer cells in the brain and spinal cord.
Eye cancer treatment
The treatment options for eye cancer depend on the diagnosis (where exactly the cancer is) and the size and stage of cancer (how far advanced it is). The earlier eye cancer is diagnosed, the better the prospects for treatment. Most people need a combination of treatments, for example, surgery and cryotherapy or radiation therapy and chemotherapy.
Treatments can have side effects, and your healthcare team will discuss this with you when they recommend your treatment plan.
The main treatments currently available for eye cancer include:
How to prevent eye cancer
There are various risk factors for eye cancer, not all of which can be managed or prevented. For example, some eye cancers have a genetic cause. However, you can limit your exposure to ultraviolet light by wearing UV protective sunglasses and limiting time spent in strong sunlight or on sunbeds. Regular eye tests will also help ensure cancer is detected sooner rather than later, allowing a better chance for effective treatment.