INTRAOCULAR CANCERS

Eye cancer refers to a cancerous growth in any part of the eye. Some eye cancers are primary, while others represent metastases from primary cancers elsewhere in the body.

DEFINITION

DESCRIPTION

Two types of cancers can be found in the eye.

- Primary intraocular cancers start inside the eyeball. In adults, melanoma is the most common primary intraocular cancer, followed by primary intraocular lymphoma.

- Secondary intraocular cancers start somewhere else in the body and then spread to the eye. These are more common than primary intraocular cancers. The most common cancers that spread to the eye are breast and lung cancers. Most often these cancers spread to the part of the eyeball called the uvea.

PRIMARY INTRAOCULAR MELANOMA (melanoma of the eye)

Intraocular melanoma is the most common type of cancer that develops within the eyeball in adults.
Melanomas develop from pigment-making cells called melanocytes that can be found in three areas of the eye: the iris, the ciliary body, and/or the choroid or posterior uvea. These three areas are collectively known as the uvea or uveal tract, which is why these cancers are also called uveal melanomas.

Incidence of ocular melanoma increases with age and may be more common in people who have atypical mole syndrome.
About 90% of intraocular melanomas develop in the choroid which make the same kind of pigment as melanocytes in the skin.
The other intraocular melanomas start in the iris (part of the uvea). These often start in a dark spot on the iris that has been present for many years and then begins to grow.

 

PRIMARY INTRAOCULAR LYMPHOMA (lymphoma of the eye)

Lymphoma is a type of cancer that starts in immune system cells called lymphocytes. Most lymphomas start in lymph nodes and in internal organs such as the stomach, lungs, and rarely, in the eyes.

There are 2 main types of lymphoma: Hodgkin disease and non-Hodgkin lymphoma. Primary intraocular lymphoma is a type of non-Hodgkin lymphoma. Most people with primary intraocular lymphoma are elderly or have immune system problems such as AIDS. Primary intraocular lymphoma is often seen along with lymphoma of the brain, known as primary central nervous system (CNS) lymphoma.

 

ORBITAL AND ADNEXAL CANCERS

Cancers of the orbit and adnexa develop from tissues such as muscle, nerve, and skin around the eyeball and are like their counterparts in other parts of the body.

The conjunctiva is the clear moist membrane that covers the front of the eye and lines the inside of the eyelid. Although rare, squamous cell cancer is the most common cancer of the conjunctiva. This type of cancer usually grows on the surface of the conjunctiva but can grow into and around the eye. It is generally slow growing (low grade), and very rarely spreads to another part of the body.