Intraocular Melanoma

Intraocular Melanoma at a Glance

• Intraocular melanoma is a disease in which malignant (cancer) cells form in the tissues of the eye.
• Although intraocular melanoma is a rare cancer, it is the most common eye cancer in adults.
• The mean age-adjusted incidence of uveal melanoma in the United States is approximately 4.3 new cases per million population, which has remained stable for the past 50 years.

Anatomy

Intraocular melanoma begins in the middle of 3 layers of the wall of the eye. The outer layer includes the white sclera (the "white of the eye") and the clear cornea at the front of the eye. The inner layer has a lining of nerve tissue, called the retina, which senses light and sends images along the optic nerve to the brain. The middle layer, where intraocular melanoma forms, is called the uvea or uveal tract, and has 3 main parts:

Iris-- The iris is the colored area at the front of the eye (the "eye color"). It can be seen through the clear cornea. The pupil is in the center of the iris and it changes size to let more or less light into the eye.

Ciliary body-- The ciliary body is a ring of tissue with muscle fibers that change the size of the pupil and the shape of the lens. It is found behind the iris. Changes in the shape of the lens help the eye focus. The ciliary body also makes the clear fluid that fills the space between the cornea and the iris.

Choroid-- The choroid is the layer of blood vessels that bring oxygen and nutrients to the eye. Most intraocular melanomas begin in the choroid.

Risk Factors

Risk factors for intraocular melanoma include the following:

• Being exposed to natural sunlight or artificial sunlight (such as from tanning beds) over long periods of time.
• Having a fair complexion, which includes the following:
• Fair skin that freckles and burns easily, does not tan, or tans poorly.
• Blue or green or other light-colored eyes.
• Older age.
• Being white.

Symptoms

Possible signs of intraocular melanoma include:

• A dark spot on the iris.
• Blurred vision.
• A change in the shape of the pupil.
• A change in vision.

Glaucoma may develop if the tumor causes the retina to separate from the eye. If this happens, there may be no symptoms, or symptoms may include the following:

• Eye pain.
• Blurred vision.
• Eye redness.
• Nausea.