An eye cancer starts in the eye. There are different types of eye cancers. To understand eye cancers, it helps to know something about the parts of the eye and what they do.

Parts of the eye

The eye has 3 major parts: the eyeball (globe), the orbit, and the adnexal structures.

Cancers in the eye (intraocular cancers)

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. These 2 cancers are the focus of this document.

In children, retinoblastoma (a cancer that starts in cells in the retina) is the most common primary intraocular cancer, and medulloepithelioma is the next most common (but is still extremely rare). These childhood cancers are discussed in our document Retinoblastoma.

Secondary intraocular cancers start somewhere else in the body and then spread to the eye. These are not truly “eye cancers,” but they are actually 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. For more information on these types of cancers, see our documents on them.