Eye Cancer Facts: Understanding Uveal Melanoma and Other Eye Cancers

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Last updated and reviewed on: September 30, 2026

Uveal melanoma is rare. Research published on NCBI's StatPearls puts the incidence in the United States at about 5 cases per 1 million people each year, and the Ocular Melanoma Foundation cites a similar figure of about 6 people per million. The American Cancer Society estimates that about 3,200 new primary cancers of the eye and eye socket are diagnosed in the United States each year (mainly melanomas), with about 530 deaths. Even though uveal melanoma is the most common cancer that starts inside the eye in adults, it is still an uncommon disease, and most people will never know anyone who has had it.

"Eye cancer" is a broad, umbrella term. It can mean several different diseases that behave in different ways, need different treatments, and have different outlooks. This guide is centered on uveal melanoma, also called intraocular melanoma or ocular melanoma, because it is the type most adults are searching for when they type "eye cancer" into a search engine, and it is how the National Cancer Institute and American Cancer Society organize their own eye cancer information. When this series says "eye cancer" without adding another name, it means uveal melanoma, the melanoma (a cancer of pigment-making cells) that starts in the choroid, ciliary body, or iris inside the eye.

Uveal melanoma is not the same disease as retinoblastoma, which is the eye cancer that mainly affects young children, usually before age 5. Retinoblastoma starts in the retina (the light-sensing layer at the back of the eye), is driven by changes in a different gene called RB1, and is treated and followed in a different way than uveal melanoma. Wherever retinoblastoma matters in this guide, it is called out clearly under its own heading so the two diseases are never confused.

Uveal melanoma is also different from several other, much rarer conditions that can affect the eye and the skin around it. These include conjunctival melanoma and conjunctival squamous cell carcinoma (cancers of the clear covering over the white of the eye), eyelid skin cancers such as basal cell carcinoma, squamous cell carcinoma, and sebaceous carcinoma, and primary lymphoma of the eye or eye socket. It is also different from eye metastases, which are cancers that started somewhere else in the body, most often the breast or lung, and then spread to the eye. Eye metastases are not primary eye cancer; they are treated as the original cancer. Finally, most pigmented spots doctors find inside the eye are a benign (harmless) choroidal nevus, essentially a freckle inside the eye, not melanoma.

If you take away only two things from this guide, they should be these. First, most uveal melanoma today can be treated without removing the eye. Eye-sparing treatments, such as plaque radiotherapy, are now the most common approach. Second, because uveal melanoma spreads through the bloodstream to the liver, sometimes many years after the eye tumor is treated, lifelong liver surveillance is a real and important part of care, not an afterthought. Both points are covered in more depth later in this guide and in our companion guide on eye cancer treatment.

What Is the Eye Made Of?

To understand uveal melanoma, it helps to know a few basic parts of the eye. The eyeball has three main layers. The outer layer is the sclera, the tough white wall that gives the eye its shape. The middle layer is the uvea, and the inner layer is the retina, the light-sensing tissue that lines the back of the eye and sends signals through the optic nerve to the brain, which turns those signals into the images you see.

The uvea is the layer that matters most for this cancer. It is made of three connected parts. The choroid is a thin sheet of blood vessels and pigment cells that sits between the retina and the sclera and feeds the retina with oxygen and nutrients. The ciliary body sits just in front of the choroid. It contains muscles that change the shape of the lens so your eye can focus, and it makes the clear fluid (aqueous humor) that fills the front of the eye. The iris is the colored, ring-shaped part of the eye that surrounds the pupil, the opening that lets light in, and it controls how much light enters the eye by widening or narrowing the pupil.

The retina, described above, is a separate structure from the uvea, even though the two sit right next to each other. The retina is where retinoblastoma starts, while the choroid, ciliary body, and iris are where uveal melanoma starts. This distinction is one of the clearest ways to tell the two diseases apart at the tissue level.

The sclera and optic nerve round out the anatomy that matters here. The sclera, the eye's outer shell, gives doctors a landmark for describing where a tumor sits and how close it is to the surface of the eye. The optic nerve carries visual signals from the retina to the brain, and it is a structure doctors watch closely on imaging, because a tumor that grows close to it can threaten vision or, less often, spread beyond the eye.

The choroid deserves special attention because it is where most uveal melanomas begin. It is rich in blood vessels, which explains why this cancer can spread through the bloodstream rather than through lymph nodes, and it is rich in melanocytes, the same pigment-making cells found in the skin, which explains why a melanoma can form there at all.

Source: National Cancer Institute

How Does Eye Cancer Start?

In a healthy eye, cells grow, divide, and die in an orderly cycle that your body controls closely. Cancer starts when this control breaks down, usually because of changes (mutations) in the genes that manage cell growth. The abnormal cells then divide out of control and can form a tumor.

Uveal melanoma starts in melanocytes, the pigment-making cells found throughout the uvea, especially the choroid. This is an important point of confusion for many patients: uveal melanoma and skin melanoma are both called "melanoma" because both start in melanocytes, but they are genetically different diseases with different causes, different behavior, and different treatments. A person's history of skin melanoma does not mean their eye is at higher risk in the same way that sun-damaged skin is.

Most uveal melanomas share specific genetic changes. According to StatPearls, the majority carry mutations in the GNAQ or GNA11 genes (two genes that help control cell growth signals), and these changes are considered an early, defining step in how the tumor forms. Other genes, including BAP1, SF3B1, and EIF1AX, are also frequently altered and help explain why some tumors behave more aggressively than others. Loss of a working copy of the BAP1 gene, along with a change called monosomy 3 (the loss of one copy of chromosome 3) and a gain of part of chromosome 8, is linked to a higher risk that the cancer will eventually spread.

Importantly, these tumor gene changes are almost always somatic, meaning they happen only inside the tumor cells during a person's lifetime, not changes a person was born with or can pass to their children. Most uveal melanoma is not inherited. A minority of cases are linked to an inherited condition called BAP1 tumor predisposition syndrome, which is covered later in this guide.

How retinoblastoma starts differently

Retinoblastoma is a different eye cancer that mainly affects young children and works differently at the genetic level. It is driven by the loss of both working copies of the RB1 gene (a gene that normally stops cells from dividing too much), inside a retinal cell. According to the NCI PDQ retinoblastoma summary, retinoblastoma can be heritable (inherited, meaning the RB1 change can be passed to future children and often affects both eyes) or nonheritable (a chance change that happens after birth, usually affecting only one eye). This genetic story is entirely separate from the GNAQ, GNA11, and BAP1 changes described above for uveal melanoma.

Where Does Eye Cancer Start?

Uveal melanoma can start in any of the three parts of the uvea, and where it starts affects how it behaves and how it is treated. According to the American Cancer Society, the choroid is by far the most common starting point. Choroid cells make the same kind of pigment as skin melanocytes, so it is not surprising that melanoma can form there.

The ciliary body is the next most common location. Because the ciliary body sits behind the iris, tumors here can grow for a long time before anyone notices them, which means ciliary body melanomas are often larger by the time they are found. Ciliary body melanomas are also more likely to spread outside the eye than tumors in the choroid or iris.

The iris is the least common location for uveal melanoma. Iris melanomas are usually easiest to notice because they often appear as a dark spot on the colored part of the eye that a person or their doctor can see directly, sometimes after it has been present for years and then starts to grow. Iris melanomas tend to grow slowly and rarely spread to other parts of the body, so people with this type generally have the best outlook of the three.

In most cases, uveal melanoma affects only one eye. It is very unusual for it to occur in both eyes at the same time, and having it in one eye does not mean the other eye is at meaningfully higher risk.

Where retinoblastoma starts

Retinoblastoma starts in the retina, not the uvea. It can affect one eye (called unilateral) or both eyes (called bilateral) at the same time. Whether a child has one or both eyes affected is one of the clues doctors use to decide whether the retinoblastoma is likely to be the heritable form.

How Does Eye Cancer Affect the Body?

A growing uveal melanoma can affect vision in several ways before it ever spreads anywhere else. As the tumor grows, it can push against or lift the retina, a problem called retinal detachment, which can cause blurred or lost vision. It can also distort the shape of the eye, cause bleeding inside the eye, or raise the pressure inside the eye, which can be uncomfortable and can itself threaten vision if not addressed. Many small tumors, however, cause no symptoms at all and are found only during a routine dilated eye exam, which is why regular eye care matters even when your vision feels normal. Our guide on eye cancer symptoms covers these warning signs in more detail.

The pattern of spread is what makes uveal melanoma unusually important to understand well. Most cancers spread first through nearby lymph nodes. Uveal melanoma is different: it spreads hematogenously, meaning through the bloodstream, and it does not typically involve lymph nodes at all, because the eye itself has no lymphatic drainage.

When uveal melanoma does spread, the liver is overwhelmingly the most common site. The NCI patient summary explains that if intraocular melanoma spreads to the liver, the cancer found there is still intraocular melanoma cells, called metastatic intraocular melanoma, not a new liver cancer. This distinction matters because the treatment approach follows the original cancer type.

One of the most distinctive and, for patients, most important features of uveal melanoma is timing. Spread to the liver can happen years, even a decade or more, after the original eye tumor was successfully treated and the eye looked completely healthy. This is very different from many other cancers, where the highest risk period is in the first few years after treatment.

This is exactly why lifelong follow-up matters so much. Because metastasis can appear so long after initial treatment, doctors typically recommend regular liver imaging, such as ultrasound or MRI, and liver function blood tests for life, not just for a few years. Genetic and gene expression profile testing of the tumor can help estimate an individual's personal risk and guide how intensive this surveillance should be, a topic explored further in our guide on eye cancer screening.

Types of Eye Cancer

Eye cancer covers several distinct diseases, and understanding the differences can help you make sense of what you read and what your care team tells you.

Cancer inside the eyeball
- Uveal melanoma: The most common primary eye cancer in adults, starting in the pigment cells of the choroid, ciliary body, or iris. This is the main subject of this guide, and it has three location-based subtypes: choroidal melanoma (most common), ciliary body melanoma, and iris melanoma (least common, generally best outlook).
- Retinoblastoma: A different disease of childhood that starts in the retina, usually before age 5, and is driven by changes in the RB1 gene rather than the GNAQ, GNA11, or BAP1 changes seen in uveal melanoma. It is covered in detail as its own separate condition throughout this series.
- Circumscribed choroidal hemangioma: A non-cancerous growth that poses no risk to a patient's life.
- Retinal hemangioblastoma: A non-cancerous tumor of the retina. If not caught early, it can cause blurry vision, vision loss, flashing lights, or floaters.
- Metastatic intraocular tumors: Other cancers that have spread to the eye. The most common are breast, lung, and gastrointestinal cancers.
Cancer of the eyelid
- Basal cell carcinoma: A type of skin cancer on the eyelid. More than 90% of eyelid cancer is this type.
- Squamous cell carcinoma: A type of skin cancer on the eyelid. Occurs less often than basal cell carcinoma but is more aggressive
- Cutaneous melanoma: A type of skin cancer on the eyelid. Accounts for about 1% of eyelid cancers.
- Sebaceous carcinoma (meibomian gland carcinoma): A rare type that affects the meibomian gland of the eyelids.
- Merkel cell carcinoma: Rare but aggressive; a fast-growing purplish or flesh-colored mass.
- Metastatic eyelid tumors: Other cancers that have spread to the eyelid.
Cancer of the Conjunctiva
- Squamous cell carcinoma: Most common type of conjunctival melanoma affecting the area around the cornea.
- Conjunctival melanoma: A rare cancer that occurs on the conjunctiva, the thin covering over the white of the eye. It tends to grow faster and return more often. Sometimes this cancer is linked to sun exposure or certain viral infections.
- Metastatic conjunctival tumors: Other cancers that have spread to the conjunctiva.
Cancer of the orbit
- Orbital sarcoma: The most common sarcoma in the eye that comes from muscle or fatty tissue.
- Orbital and optic nerve meningiomas: Benign (non-cancerous) tumors that do not spread.
- Metastatic orbital tumors: Other cancers that have spread to the conjunctiva.
Lacrimal gland tumors
- Adenoid cystic carcinoma: A rare cancer that can spread and become life-threatening.
- Pleomorphic adenoma: The most common benign (non-cancerous) tumor in the lacrimal gland.
- Other lacrimal gland carcinomas: Includes adenocarcinoma, squamous carcinoma, or mucoepidermoid carcinoma of the lacrimal gland.
- Metastatic lacrimal gland tumors: Other cancers that have spread to the lacrimal gland.
Lacrimal sac and nasolacrimal duct cancers
- Squamous cell carcinoma: Second most common form of skin cancer with abnormal, rapid growth of squamous cells.
- Transitional cell carcinoma: Cancer of the lacrimal sac.
- Metastatic lacrimal sac and nasolacrimal duct tumors: Other cancers that have spread to the lacrimal sac and nasolacrimal duct.
Lymphomas of the eye
- Diffuse large B -cell lymphoma: The most common type of lymphoma in the vitreous and sometimes the orbit. It is an aggressive form of non-Hodgkin's lymphoma.
- Marginal zone lymphoma and follicular lymphoma: Slow-growing forms of non-Hodgkin lymphoma. Marginal zone lymphoma involves the conjunctiva. Marginal zone lymphoma and follicular lymphoma may show up as nodules in the eyelid or around the eye.

It is worth stating plainly: eye metastases, cancer that started elsewhere in the body (most often the breast or lung) and then spread to the eye, are not primary eye cancer. The American Cancer Society notes that these secondary eye cancers are actually more common overall than primary eye cancers, though they are a different problem entirely and are treated as the original cancer type, not as a new eye cancer.

Related Conditions to Eye Cancer

The vast majority of pigmented spots found inside the eye are not melanoma at all. They are a choroidal nevus, a benign (harmless) pigmented spot on the choroid, essentially a freckle inside the eye. According to a fact sheet from the American Society of Retina Specialists, choroidal nevi are estimated to affect about 5% of people in the United States overall, with the rate varying by background, and they become somewhat more common with increasing age. Most nevi cause no symptoms at all and are found only on a routine dilated eye exam.

Other benign spots and lesions can also appear in the choroid or iris, and most of these are harmless too. What matters is not the presence of a pigmented spot by itself, but whether it shows features that suggest it could be changing into a melanoma.

When a doctor finds a suspicious spot, the usual approach is careful monitoring rather than immediate treatment. This typically includes retinal photographs to document the exact size and appearance of the spot, and sometimes ultrasound to measure its thickness, repeated at regular intervals (often every 6 to 12 months for lower-risk spots, more often if any risk features are present) to see whether it is stable or growing over time. Growth over a relatively short period, along with certain features such as increased thickness, fluid under the retina, or symptoms like new floaters or blurred vision, is what leads a doctor to suspect the lesion has become a melanoma.

Reassurance here is grounded in real numbers, not guesswork. The American Society of Retina Specialists estimates that a choroidal nevus transforms into melanoma at a rate of only about 1 in 9,000 per year, meaning the overwhelming majority of these spots will remain benign for the rest of a person's life. If you have just been told you have a choroidal nevus after a dilated eye exam, this is genuinely good news, paired with a simple plan: regular monitoring rather than urgent treatment.

This is also a good place to repeat an earlier point. If you were told a pigmented spot was found in your eye, it is far more likely to be a benign nevus than uveal melanoma, given how much more common nevi are than melanoma. Your eye doctor or an ocular oncologist (a doctor who specializes in eye tumors) is the right person to interpret your specific findings and recommend a monitoring schedule.

What Are the Genetic and Risk Factors?

Several factors are linked to a higher chance of developing uveal melanoma, though none of them guarantee it will happen, and many people who develop this cancer have no known risk factor at all. Light eye color (blue, green, or gray irises), fair skin that burns easily, and older age are the most consistently reported risk factors across studies.

Ultraviolet (UV) light exposure has been studied as a possible risk factor, similar to its well-established role in skin melanoma, but it is important to be honest about the evidence here. The research on UV exposure and uveal melanoma is weaker and less consistent than the research linking UV exposure to skin cancer, so sun exposure should not be treated as a proven, established cause of uveal melanoma the way it is for skin melanoma.

A rare condition called oculodermal melanocytosis (also known as ocular melanocytosis, or nevus of Ota when it also involves the skin) raises the risk of uveal melanoma more clearly than sun exposure does. This condition causes extra pigment in and around the eye from birth and is associated with a meaningfully higher lifetime risk of uveal melanoma, which is why people with this condition are often advised to have regular eye exams. Other reported risk factors include dysplastic nevus syndrome (a tendency to form many unusual skin moles) and having a family history of uveal melanoma.

A minority of uveal melanoma cases, thought to be a small percentage overall, occur in people with an inherited condition called BAP1 tumor predisposition syndrome, caused by a germline (inherited) mutation in the BAP1 gene. People with this syndrome are more likely to develop uveal melanoma at a younger age than average and are also at higher risk for other specific cancers, discussed in the next section. Our guide on risk factors for eye cancer explores all of these factors in more depth.

Retinoblastoma genetics and genetic counseling

Retinoblastoma genetics work differently and matter for the whole family, not just the child. About 45% of retinoblastoma cases are heritable, meaning they involve a germline RB1 mutation that can be passed from parent to child; these cases often affect both eyes or multiple spots within one eye. The remaining, nonheritable cases happen when the RB1 mutation occurs by chance in a retinal cell after birth and usually affect only one eye. Because it is not always possible to tell which type a child has just from family history, genetic counseling and RB1 gene testing are real, actionable steps that can clarify a child's own risk, guide how closely other family members should be watched, and inform whether future siblings should have early eye exams. A genetic counselor can also help parents understand and cope with what the test results mean for their family.

What Are the Related Cancers to Eye Cancer?

For the minority of people with inherited BAP1 tumor predisposition syndrome, uveal melanoma is only part of the picture. This syndrome also raises the lifetime risk of malignant mesothelioma (a cancer of the lining around the lungs or abdomen), kidney cancer (specifically renal cell carcinoma), and melanoma of the skin. Because of this, people known to carry a BAP1 mutation are often followed with additional cancer screening beyond eye exams, and genetic counseling is recommended for their close relatives as well.

For survivors of hereditary (heritable) retinoblastoma, the long-term picture also includes a higher risk of other cancers later in life. Research summarized in StatPearls notes that people with hereditary retinoblastoma have an increased lifetime risk of second cancers, particularly osteosarcoma (a bone cancer) and other soft tissue sarcomas, along with skin melanoma. Notably, the risk of a second cancer rises about fivefold in people who were treated with external beam radiation therapy for their retinoblastoma, which is one reason treatment approach has long-term consequences and why many centers now favor other eye-sparing methods, such as chemotherapy or focal laser treatments, when they are appropriate for the tumor.

It is worth repeating the distinction between these related cancers and eye metastases one more time, because the two ideas are easy to confuse. BAP1 syndrome and hereditary retinoblastoma involve a person's own increased risk of developing other, separate cancers over their lifetime. Eye metastases are the opposite situation: a cancer that already exists somewhere else in the body spreading into the eye. The cancers that most often spread to the eye this way are breast cancer and lung cancer, along with other cancers less commonly. As stated earlier in this guide, eye metastases are not primary eye cancer, and they are treated according to the original cancer, not as uveal melanoma or retinoblastoma.

Whatever your situation, decisions about additional screening, genetic testing, or treatment approach should always be made with your own care team, who can weigh your specific diagnosis, family history, and test results. This guide cannot tell you what your own risk is or what to do about it; it is meant to help you understand the landscape and ask better questions, a goal shared by our companion guide on questions to ask about eye cancer.