Education: Eye Cancer
Eye cancer is a very rare kind of cancer that starts somewhere in or on the eye or in the skin of cells around the eye. The American Cancer Society estimates that approximately 2,500 new cases are diagnosed annually in the U.S.
What Are the Different Types of Eye Cancer?
Primary intraocular cancers start in the eyeball. In adults, melanoma is the most common primary form, followed by primary intraocular lymphoma. When melanoma develops in the eyeball, it is usually in the middle layer known as the uvea, which is why these cancers are also called uveal melanomas.
Most often intraocular melanomas start in the iris. These are the easiest for the patient and doctor to see because they often arise in a pigmented spot on the iris that has been present for many years and then begins to grow. These melanomas usually are fairly slow growing, and they rarely spread to other parts of the body.
Lymphoma is a type of cancer that starts in immune system cells called lymphocytes. It usually starts in lymph nodes, which are bean-sized collections of immune system cells. But lymphomas can also start in internal organs such as the stomach, lungs, and rarely in the eyes. Most people with primary intraocular lymphoma are elderly or have immune system problems.
Secondary intraocular cancers start somewhere else in the body, and then spread to the eye. The most common cancers that spread to the eye are breast and lung cancers.
Primary eye cancers can occur at any age, but most occur in people over age 50. Other risk factors for developing intraocular melanoma include:
- Certain inherited conditions such as dysplastic nevus syndrome in which people have abnormal moles of the skin and an increased risk of skin melanoma, may also increase the risk for developing melanoma of the eye
- Sun exposure
- Certain occupations such as welders, farmers, fishermen, chemical workers, and laundry workers have a higher risk of eye melanoma
- Light skin and/or eye color
The only known risk factor for primary lymphoma of the eye is having a weakened immune system.