What is eye cancer?

Last medical review:

Eye cancer starts in the cells in or around the eye. The eye is the organ that lets you see. Each eye is made up of the:

  • eyeball
  • adnexal structures of the eye (the eyelid, conjunctiva and tear gland)
  • eye socket

Your eyes connect to the central nervous system (CNS) by the optic nerve. This nerve runs out of the back of each eye to the brain.

Cells in or around the eye sometimes change and no longer grow or behave normally. These changes may lead to non-cancerous (benign) conditions such as a nevus (eye mole). They can also lead to non-cancerous tumours such as a choroidal hemangioma or pterygium.

Changes to cells in or around the eye can also cause precancerous conditions. This means that the abnormal cells are not yet cancer, but there is a chance that they will become cancer if they aren’t treated. The most common precancerous condition of the eye is primary acquired melanosis (PAM) of the conjunctiva. Another precancerous condition of the eye is conjunctival intraepithelial neoplasia (CIN).

But in some cases, changes to the cells in or around the eye can cause eye cancer. A cancerous (malignant) tumour is a group of cancer cells that can grow into nearby tissue and destroy it. The cancer can also spread (metastasize) to other parts of the body.

There are different types of eye cancer that start in different types of cells.

Most often, eye cancer in adults starts in melanocytes within the eyeball. Melanocytes make melanin, which is what gives the eyes, skin and hair their colour. Melanoma of the eye most often develops in the uvea, which is part of the eyeball. This type of eye cancer is called uveal melanoma. It is a type of intraocular melanoma. (Intraocular means “within the eyeball.”)

The second most common type of eye cancer in adults begins in lymphocytes of the eye. Lymphocytes are a type of white blood cell. Lymphoma of the eye is often called intraocular lymphoma. In most cases, it is a type of non-Hodgkin lymphoma.

Another type of cancer that can develop in the eye is squamous cell carcinoma (SCC). Squamous cells are flat, thin cells that line many parts of the body. They are in the conjunctiva and eyelids. When SCC affects the eyelids, it is considered a type of non-melanoma skin cancer.

Retinoblastoma is the most common eye cancer in children. It starts in the cells of the retina. Find out more about retinoblastoma.

Other types of cancer can spread to the eye, but this is not the same disease as primary eye cancer. Cancer that starts in another part of the body and spreads to the eye is called eye metastasis. Eye metastasis is more common than primary eye cancer. It is not treated in the same way as primary eye cancer. Cancer most often spreads to the eye from the breast and lung.

Expert review and references

  • Tina Felfeli, MD
  • A Detailed Look At The Eye. Canadian Association of Optometrists; 2023. https://opto.ca/.
  • Abramson DH, Schefler AC, Dunkel IJ, McCormick B, Dolphin KW. Adult ophthalmic oncology: Ocular diseases. Kufe DW, Pollock RE, Weischselbaum RR, et al. (eds). Holland-Frei Cancer Medicine. 6th ed. Hamilton, ON: BC Decker; 2003: 85.
  • American Cancer Society. What is Eye Cancer. 2023. https://www.cancer.org/.
  • Cancer Research UK. What is Eye Cancer. 2021. https://www.cancerresearchuk.org/.
  • Finger PT, Pavlick A, Sauerwein WAG. Intraocular melanoma. DeVita VT Jr, Lawrence TS, Rosenberg S. eds. DeVita Hellman and Rosenberg's Cancer: Principles and Practice of Oncology. 12th ed. Philadelphia, PA: Wolters Kluwer; 2023: Kindle version, [chapter 78], https://read.amazon.ca/?asin=B0BG3DPT4Q&language=en-CA.
  • Finger PT. Eyelid Tumors: General Information. New York Eye Cancer Centre; https://eyecancer.com/. March 19, 2024.
  • Johns Hopkins Medicine. Eye Tumours. Baltimore, MD: https://www.hopkinsmedicine.org/. March 19, 2024.
  • Johns Hopkins Medicine. Pinguecula and Pterygium. Baltimore, MD: https://www.hopkinsmedicine.org/. March 19, 2024.
  • Porter D. What is ocular melanoma?. Eye Diseases and Topics, A-Z. American Academy of Opthalmology; 2022. https://www.aao.org/eye-health/a-z.
  • Shields JA, Shields CL, Mashayekni A, Marr BP, Benavides R, Thangappan A, et al.. Primary acquired melanosis of the conjunctiva: Experience with 311 eyes. Transactions of the American Ophthalmology Society. 2007: 105:61–72.

The eyes

Eye cancer starts in the eye. The eye is more than just your eyeball. Your eyes are a part of the central nervous system and work with your brain to let you see.

Cancerous tumours of the eye

Uveal melanoma is a type of intraocular melanoma. It is the most common type of cancerous tumour of the eye. Lymphoma of the eye is the second most common type. There are also rarer types of eye tumours.

Precancerous conditions of the eye

Precancerous conditions of the eye are changes to cells that make them more likely to develop into cancer.

Non-cancerous tumours of the eye

Eye moles (nevi) and hemangiomas are the most common non-cancerous eye tumours.

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