Risks and causes of eye cancer

Anything that can increase your risk of getting a disease is called a risk factor. Having one or more of these risk factors doesn't mean you will definitely develop eye cancer.

Eye cancer is very rare. Around 851 cases are diagnosed in the UK each year. 

There are different types of eye cancer and there are possible risk factors for the different types. Overall, the risk of developing an eye cancer is increased as you get older. About a quarter of all people diagnosed with eye cancer in the UK are aged 75 and over. The exception to this is a type called retinoblastoma. This usually affects children under the age of 5.

Melanoma of the eye

The possible risk factors for eye melanoma include:

Age

This type is more common in older people. The average age of diagnosis is around 60 years.

Race

Melanoma of the eye is more common in white than black people.

Eye colour and skin tone

People with blue, grey or green eyes are more likely to develop eye melanoma than people with brown eyes. The risk is also higher in people with fair skin, or with freckles.

People who have abnormal brown spots (pigmentation) on their uvea (called oculodermal melanocytosis) or iris (called iris naevus) are at an increased risk of developing eye melanoma.

Moles

Some families tend to have large numbers of moles on their skin or moles that are unusual (doctors call them atypical). The atypical moles tend to be an irregular shape or colour. They also have a tendency to become cancerous. People with moles like this have a higher than average risk of skin melanoma and eye melanoma.

Inherited cancer syndromes

Doctors have identified a rare inherited condition called BAP1 cancer syndrome. Families with this have a change (mutation) in the BAP1 gene. People with this gene change have an increased risk of uveal melanoma, skin melanoma and some other cancers. The uvea is the middle layer of the eye. Most adult eye cancers are a type called uveal melanoma.

Exposure to ultraviolet (UV) radiation for some workers.

Some studies have reported a slightly increased risk of melanoma of the eye in people working as welders. This risk is may be due to exposure to ultraviolet radiation.

Use of sunbeds

Exposure to artificial UV radiation, for example sunbeds, increases the risk of eye melanoma.

Squamous cell eye cancer

The risk factors for squamous cell eye cancer include:

Age and gender

This is mostly a cancer of the older population in the UK, with an average age of 60 years. Men are affected more than women.  

Sunlight and ultraviolet radiation

Sun and UV exposure has been linked to a higher risk of squamous cell carcinoma of the eye. This type of cancer is more common in areas of the world where the sun’s light is stronger than in the UK. 

Infection with HIV

People who have HIV are at a higher risk of squamous cell carcinoma of the conjunctiva of the eye. This is almost certainly because of the effect of the virus on their immune system.

Drugs that suppress the immune system

People who have an organ transplant need to take drugs to stop their immune systems rejecting the new organ. These drugs damp down the immune system generally. Because of this, these people are at an increased risk of some types of cancer, including squamous cell carcinoma of the eye.

Human papilloma virus infection

Human papilloma virus (HPV) may cause squamous cell carcinoma of the eye in combination with other factors. The virus causes squamous cell cancers elsewhere in the body. Infection with HPV is very common and it usually doesn't cause any problems at all. There are probably other factors working with the HPV that explain why some people get it and others don’t.

Lymphoma of the eye

The average age at diagnosis for lymphoma of the eye is between 50 and 60 years.

Anyone whose immune system is not working as well as it should may be more likely to develop lymphoma of the eye. This includes people who:

• are taking drugs to stop organ rejection after a transplant
• have HIV or AIDS
• have auto immune diseases such as rheumatoid arthritis
• are born with rare medical syndromes which affect their immunity

People without these risk factors can still develop an eye lymphoma. There appears to be an increasing number of cases in people who don't have problems with their immune systems. The reason for this is not yet clear. Improved methods of diagnosing this rare cancer is one possible explanation.

Kaposi's sarcoma of the eye

Kaposi’s sarcoma is mostly seen on the skin but can affect other parts of the body such as the eyes.

This is a very rare eye cancer caused by a virus. It is usually seen in people with a weak immune system as a result of advanced HIV (human immunodeficiency virus). Rarely It can develop in the elderly and people with problems with their immune system (but do not have HIV).

Retinoblastoma

Retinoblastoma is a rare type of eye cancer. In Britain around 45 children each year are diagnosed. It most commonly affects children under the age of 5.

Inherited gene changes

About 4 out of 10 retinoblastomas (40%) can run in families. Some children are born with a change (mutation) in the retinoblastoma gene (RB1 gene) that they inherit from one of their parents. Or this gene change happened in the very early stages of the child's development in the womb. They can then pass on this mutation to their children in the future.