Risks for eye cancer
Certain behaviours, substances or conditions can affect your risk, or chance, of developing cancer. Some things increase your risk and some things decrease it.
In Canada, the number of new cases of eye cancer diagnosed each year (called the incidence) starts to increase in people in their early 30s. Eye cancer generally affects men and women equally until the age of 50. Then it occurs more often in men.
The following can increase your risk for eye cancer. Most of these risks can't be changed. But in some cases there are things you can do to lower your risk.
Primary acquired melanosis
Primary acquired melanosis (PAM) is a condition of the conjunctiva, which is a
clear
PAM mostly affects people with light-coloured skin, hair or eyes. It increases the risk of melanoma of the conjunctiva, a type of eye cancer.
Ocular melanocytosis
Ocular melanocytosis (also called oculodermal melanocytosis or nevus of Ota) is a rare condition of the eye that is present at birth. People with this condition have a high number of melanocytes and more melanin than normal in and around their eyes.
Ocular melanocytosis increases the risk of developing intraocular melanoma, the most common type of eye cancer.
Light-coloured skin, eyes and hair
People with fair or light-coloured skin have a higher risk of developing intraocular melanoma than people with other skin types. People with blonde or red hair and blue, green or grey eyes also have a higher risk of developing intraocular melanoma. Their risk is greater because people with these features have less melanin. Melanin gives colour to your skin, hair and eyes. Experts think that it also helps protect the skin from ultraviolet radiation (UVR).
Having freckles may increase the risk of developing eye cancer, but not all studies have found that this is a risk.
Indoor tanning
Tanning beds and sun lamps give off ultraviolet radiation (UVR), which can damage the eyes and increase the risk for intraocular melanoma.
The evidence isn't as strong for outdoor sun exposure as a risk for eye cancer as it is for indoor tanning. But scientists believe sun exposure might be a risk for eye cancer for several reasons. Studies have shown that eye melanomas develop in the part of the eye that gets the most sunlight. Some evidence also suggests that people who work outside may have a higher risk of developing eye cancer. And scientists point out that melanoma of the eye and melanoma of the skin have some of the same risks, like having light-coloured skin or eyes.
Skin moles
A mole is a non-cancerous growth on the skin that is usually tan, brown or the same colour as your skin. They are not usually present at birth, but often begin to appear in childhood. People with skin moles have a higher risk of developing melanoma in the uvea (called uveal melanoma). The uvea is the middle layer of the wall of the eye, which is the outer part of the eyeball.
Having atypical (abnormal) skin moles increases the risk of developing intraocular melanoma. An atypical skin mole (also known as a dysplastic nevus) looks different from a normal mole. Many atypical moles are at least 5 mm (which is larger than a normal mole), have an irregular shape and have undefined borders.
Familial atypical multiple mole melanoma (FAMMM) syndrome (sometimes called
dysplastic nevus syndrome) is an
An eye mole, called ocular nevus, is a non-cancerous growth found in the eye. While it is like a skin mole, studies haven't shown that having an eye mole increases the risk of eye cancer.
Welding
Welders have a higher than average risk of developing eye cancer, particularly intraocular melanoma. This increased risk is likely due to exposure to ultraviolet radiation (UVR) from welding tools. It could also be due to exposure to other harmful agents in the workplace.
HIV
HIV is a virus that weakens the body's immune system and causes AIDS. People with an HIV infection have a higher risk of developing lymphoma of the eye and squamous cell carcinoma (SCC) of the conjunctiva.
Possible risks
The following have been linked with eye cancer, but more research is needed to know for sure that they are risks:
- family history of ocular melanoma
- genetic mutations (changes)
- certain jobs, like commercial cooking or working with chemicals
Understanding your cancer risk
To make the decisions that are right for you, ask your healthcare team questions about risks. Learn how cancer can be prevented and what you can do to reduce risk.