Causes and Risk Factors of Ocular Melanoma

Although it's not precisely known what causes Ocular melanoma, there are predisposing factors that can raise the risk. Ocular melanoma affects about 2,500 adults in the United States each year.

The three layers of the eye are the sclera (the white covering), the uvea (the middle layer), and the retina (the light-sensitive layer at the back of the eye). Most often, ocular melanoma develops in the uvea.

Ocular melanoma starts in the cells of the eye that produce melanin, the pigment that gives the eye its color. It develops when the melanocytes (cells that produce the dark pigment melanin) of the eye begin to multiply without apparent reason.

This article will look at the most common causes and risk factors of ocular melanoma, the role genetics plays, and how lifestyle may factor in developing the condition.

Common Causes

While no one knows for sure why ocular melanoma arises, some factors appear to set the stage for it to happen. People who are most likely to develop this condition appear to have some of the following predisposing factors:

• Lighter-colored eyes, such as blue or green
• Having light-colored skin that burns easily
• Being in a middle/older age bracket, since it's mostly diagnosed in people in their 50s and rarely in children or those over age 70
• Having abnormal moles (dark pigmented spots) from conditions that may run in the family such as dysplastic nevus syndrome
• Having eyelid pigmentation that is abnormal
• Having greater than normal pigmentation in the middle uveal layer of the eye
• Observing a freckle on the eye's surface

Ocular melanoma is diagnosed more often in White people.

Genetics

Although genetics may play a role in the development of ocular melanoma, the connection has not yet been firmly established. Still, genetic factors do exist.

People at greater risk for ocular melanoma tend to have what's known as a BAP1 cancer predisposition syndrome. This is an inherited condition that raises the risk of developing tumors. The BAP1 gene suppresses tumors and repairs DNA damage in cells. It is also involved in spurring cell death (apoptosis) when needed.

The BAP1 gene is on chromosome 3. About 50% of those with ocular melanoma have a loss of genetic material on chromosome 3, as do about 70% of people with uveal cancer that spreads outside of this area. Sometimes chromosome 3 may be missing, and other times it may just be altered.

Other chromosomes that tend to have abnormalities in ocular melanoma cases include 1, 6, and 8. Some genes that also have been associated with ocular melanoma include GNAQ, GNA11, PLCB4, CYSLTR2, EIF1AX, and the combination gene SRSF2/SF3B1.

As research progresses, more will be understood about how genetics may factor in to developing ocular melanoma.

Lifestyle Risk Factors

While there's nothing you can do to change your genetics, race, or age, lifestyle may be another matter. These are factors you can actually potentially control once you are aware of them. Lifestyle factors that may elevate your risk of ocular melanoma include:

• Having spent time in a tanning bed or using an artificial ultraviolet (UV) light even decades ago can increase your risk of ocular melanoma.
• Being a sun worshipper, either now or in the past, may not only increase your risk for melanoma of the skin, but also of the eye.
• Workplace exposure to UV radiation can increase risk.
• Exposure to certain chemicals may be a factor, but this remains unproven.
• Having certain occupations, such as a welder, may put individuals at higher risk for some forms of ocular melanoma, but more research is needed to confirm this.

One step that anyone can take to help ward off ocular melanoma is to wear UV-protective sunglasses while outside whenever possible. Also, staying out of the sun as much as possible may potentially be helpful.

Summary

Ocular melanoma is the most common type of primary eye cancer among adults. Unfortunately, it is not clear exactly what causes it to occur. People who are around age 55, who have light-colored skin or blue or green eyes, or who come from a family that tends to develop abnormal moles, among other factors, may have an increased risk.

Genetics is also being investigated in the development of ocular melanoma. Investigators are studying the BAP1 gene, which has a role in tumor suppression, as well as other potential genetic targets.

It is thought that avoiding lifestyle factors such as using tanning beds or spending a lot of time in the sun can help reduce the risk of ocular melanoma.

A Word From Verywell

A diagnosis of ocular melanoma may feel overwhelming. While there are still some unknowns about the causes of this rare primary cancer of the eye, investigators already know a great deal and are learning more every day. It is important to understand your risk and the steps you can take to possibly avoid new problems going forward.