Ocular Melanoma: Definition, Causes, Symptoms, Diagnosis, and Treatments

Ocular melanoma is defined as a type of eye cancer, often occurring in the uveal part of the eye. Ocular melanoma may also be known as uveal melanoma or choroidal melanoma, depending on where the melanoma is occurring. The causes of ocular melanoma are not definitively known, however, there are several risk factors that may increase the likelihood of developing ocular melanoma, such as having a fair complexion, having light-coloured eyes, being of older age, abnormal growths or lesions on the eye, a family or personal history of melanoma and certain skin conditions. Eye cancer symptoms in the case of ocular melanoma may not be apparent in the early stages. When symptoms of ocular melanoma occur, they may include an iris that has a dark spot, a change in pupil shape, blurry or problematic vision, a flashing light sensation, a bulging eye, and changes in the eyeball’s position or socket movement. Ocular melanoma can be diagnosed by an optometrist or other healthcare professionals using an eye test. The tests that may be used in the diagnosis of ocular melanoma may include ophthalmoscopy, ultrasound and a biopsy. Treatment for ocular melanoma can include eye surgery, photocoagulation, radiation therapy, targeted therapy, thermotherapy, active surveillance and immunotherapy. Ocular melanoma can be either malignant meaning it can spread, or benign, according to NORD the National Organisation for Rare Disorders.

Ocular melanoma is a rare but serious condition. It is important to seek medical attention if you have symptoms of ocular melanoma.

What is Ocular Melanoma?

Ocular Melanoma or eye melanoma, is a type of cancer that occurs in the eye. Melanoma is a type of cancer that affects melanin-producing cells, which are what give the body its skin colour, according to the Cancer Council. As the eyes have melanin-producing cells, called melanocytes, melanoma can also occur in the eye. Ocular melanoma, also known as uveal melanoma, often occurs in the uvea, which is the middle part of the eye. According to NORD, the National Organisation for Rare Disorders, ocular melanoma is known to appear often in the choroidal part of the eye, found within the uvea. Ocular melanoma may be known as choroidal melanoma if it occurs in the choroid. Ocular melanoma is a rare type of cancer, however, it is the most common eye-related cancer in adults, according to the American Academy of Ophthalmology.

A diagram of ocular melanoma in the structure of the eye.

What is the Other Term for Ocular Melanoma?

There are several other terms for ocular melanoma including uveal melanoma. Uveal melanoma refers to ocular melanoma in the uveal part of the eye. The uvea is the middle layer of the eye and includes several important structures within the eye such as the ciliary body, the iris, and the choroid, according to the Cancer Council. Ocular melanoma may be referred to as choroidal melanoma if it occurs in the choroid. Ocular melanoma may also be referred to as eye cancer, which is an umbrella term encompassing ocular melanoma and other types of eye cancers.

What Causes Eye Melanoma?

The causes of eye melanoma or ocular melanoma are not definitively known. According to the American Academy of Ophthalmology, ocular melanoma develops when pigment cells in the eyes, the melanocytes, grow incorrectly and as a result, contain errors. These errors multiply, gathering in the eye, and leading to melanoma. Though there are no definitive eye cancer causes in the case of ocular melanoma, some risk factors may increase the likelihood of melanoma, such as light-coloured eyes, fair skin, older age and a family or personal history of melanoma. Exposure to UV light has been theorised to be linked to ocular melanoma, however, this is a topic of ongoing debate, with inconclusive evidence.

In What Part of the Eye Does Ocular Melanoma Occur?

Ocular melanoma most commonly occurs in the uveal part of the eye. The uvea is the middle layer of the eye, with the other layers consisting of the sclera at the front of the eye, and the retina at the back, according to the American Academy of Ophthalmology. The uvea contains the coloured part of the eye called the iris, muscle tissue called the ciliary body and the choroid according to NORD, the National Organisation for Rare Disorders.

What are the Risk Factors for Ocular Melanoma?

There are several risk factors that may increase a person’s likelihood of developing ocular melanoma including a fair skin complexion, light-coloured eyes, older age, pigmentation or abnormal growths or lesions on the eye, a family or personal history of melanoma and certain skin conditions. The risk factors for ocular melanoma are listed below.

A Fair Complexion: Having a fair complexion, or fair skin and hair colour, can increase the likelihood of melanoma as this means a person has less melanin, which is the pigment that protects the skin, according to Cancer Research UK.
Light-coloured Eyes: Light-coloured eyes can be a risk factor for ocular melanoma as, according to the article Iris Colour and the Risk of Developing Uveal Melanoma, people with lighter eyes may not have the same type and ratio of melanin as those with darker eyes, specifically eumelanin.
Older Age: Older age may be a risk factor for ocular melanoma, with the average age of diagnosis in Australia at 62, according to the Australian Cancer Council. However, ocular melanoma can occur in people of all ages.
Abnormal Growths or Lesions on the Eye: Certain abnormal growths or lesions on the eye, such as an eye freckle, may increase the risk of ocular melanoma, according to the Cancer Council.
A Family or Personal History of Melanoma: People who have a family history or personal history of melanoma may have a higher risk of developing ocular melanoma.
Certain Skin Conditions: There are certain skin conditions that may increase the risk of ocular melanoma including dysplastic nevus syndrome, which causes abnormal moles on the skin.

An infographic detailing the risk factors for ocular melanoma.

Are Age and Gender Factors that May Cause Ocular Melanoma?

Older age and gender do play a factor in the risk of developing ocular melanoma, as well as how the melanoma may present itself. Older age is considered a risk factor for ocular melanoma, with the average age of diagnosis in Australia at 62 years, according to the Australian Cancer Council. Gender is a factor that may also play a role in the development and presentation of ocular melanoma. According to the American Cancer Society, ocular melanoma is marginally more common in men than women. A further study by Damato and Coupland titled Differences in uveal melanomas between men and women from the British Isles posits that the presentation of uveal melanoma in men and women can also be different, with men displaying uveal melanoma that was larger in size than women.

How Often Do Children Experience Ocular Melanoma?

Instances of children experiencing ocular melanoma are rare but have been reported. According to a patient study by Shields, Kaliki, Arepalli, Atalay, Manjandavida, Pieretti and Shields, called Uveal melanoma in children and teenagers, only 1% of the 8033 people in the study aged 20 years or younger, had ocular melanoma. Ocular melanoma is a type of eye cancer that can affect anyone of any age, however, those who are older are more likely to develop this condition.

What are the Signs and Symptoms of Ocular Melanoma?

Ocular melanoma is a type of eye cancer that may not initially cause obvious signs or symptoms. According to NORD, the National Organisation for Rare Disorders, signs and symptoms of ocular melanoma can be dependent upon the size of the melanoma, its location and whether or not it is affecting the retina. When signs and symptoms of ocular melanoma occur, they may include an iris that has a dark spot, a change in pupil shape, blurry or problematic vision, a flashing light sensation, a bulging eye, and differences in the position or movement of the eyeball in the eye socket. If you have any symptoms of the eye cancer known as ocular melanoma, is important to see an optometrist as soon as possible. The possible ocular melanoma symptoms are listed below.

Iris has a Dark Spot: If the iris has a dark spot it may be a sign of melanoma.
A Change in Pupil Shape: A change in pupil shape may indicate that ocular melanoma is present.
Blurry or Problematic Vision: Blurry or problematic vision, which may include loss of peripheral vision or noticing eye floaters, could be a sign or symptom of ocular melanoma.
Flashing Light Sensation: A flashing light sensation, which may include seeing streaks of light, can be a symptom of ocular melanoma.
A Bulging Eye: A bulging eye may be a sign of ocular melanoma.
Differences in the Position or Movement of the Eyeball in the Socket: Differences in the position or movement of the eyeball in the eye socket may be an indication of ocular melanoma.

1. Iris has a Dark Spot

An iris that has a visible dark spot on it, often one that is growing, may be a sign of ocular melanoma. The iris is the coloured part of the eye. According to the Cleveland Clinic, the iris helps to control the pupil, which allows light into the eye. Some forms of ocular melanoma may not be visible to the eye, especially if they are deeper in the layers of the eye like in the uvea or choroid. Ocular melanoma may also present as a dark spot on the whites of the eye or on the conjunctiva.

2. A Change in Pupil Shape

A change in pupil shape may be a sign or symptom of ocular melanoma. The pupil is the dark circular structure at the front of the eye, surrounded by the iris, also known as the coloured part of the eye. The role of the pupil is to help let light into the eye. If the pupil has changed in shape or size, including getting larger or looking like an asymmetrical abstract shape, this may indicate that ocular melanoma is present.

3. Blurry or Problematic Vision

Blurry or problematic vision can be a symptom of ocular melanoma. Blurry vision refers to vision that is not sharp and looks cloudy or hazy. According to NORD, the National Organisation for Rare Disorders, if ocular melanoma occurs in the ciliary body, it may affect the lens of the eye, which may lead to this blurred vision. Problematic vision can refer to several vision impairments, however, in the case of ocular melanoma, problematic vision can include loss of peripheral vision or seeing floaters. Loss of peripheral vision means the loss of vision on the sides, out of the corner of your eyes. Seeing floaters can be defined as seeing specks or spots in a person’s vision. Floaters can be a result of a change in the fluid that fills the eye, called vitreous fluid.

If you have blurry or problematic vision such as peripheral vision loss or eye floaters, it is important to seek advice from an optometrist as soon as possible.

4. Flashing Light Sensation

A flashing light sensation, referring to the sensation of seeing flashes or streaks of light in a person’s vision, may be a symptom of melanoma. A flashing sensation in the eye is often caused when the vitreous gel in the eye gets smaller in size or alters in some way, which pulls on the retina, according to the American Academy of Ophthalmology. The retina is the layer of the eye that receives light, turns this light into electrical signals and sends them to the optical nerve. According to the New York Eye Cancer Centre, choroidal melanoma can affect the retina and optic nerve, which may lead to this light-flashing sensation.

5. A Bulging Eye

A bulging eye may be a symptom of ocular melanoma. A bulging eye, called proptosis, refers to the eye bulging or moving out of its natural position in the eye socket, according to the Cleveland Clinic.

6. Differences in the Position or Movement of the Eyeball in the Socket

Differences in the position or movement of the eyeball in the socket may be a sign or symptom of ocular melanoma. The socket refers to the bone structure or cavities that house the eyes and help to protect them. If the eye is moving differently or feels out of place in the socket, this may be an indication of ocular melanoma.

How is Ocular Melanoma Diagnosed?

Ocular melanoma is most often diagnosed by an optometrist during an eye test. As ocular melanoma may not show symptoms until its later stages, some people may find they have ocular melanoma during their routine eye test without being aware they have it. If you do have symptoms of ocular melanoma such as a dark spot on the iris, blurry vision, or sensations of flashing lights or floaters, it is important to see an optometrist or medical professional as soon as possible.

What are the Eye Exams Needed to Diagnose Ocular Melanoma?

The eye tests or eye exams that may be needed to diagnose ocular melanoma include an ophthalmoscopy, an ultrasound and a biopsy. The eye exams needed to diagnose ocular melanoma are listed below.

Ophthalmoscopy: Ophthalmoscopy refers to an eye test that examines the fundus or the back part of the eye including the retina, choroid and optic nerve. Ophthalmoscopy may include a dilated fundus exam, in which eye drops are instilled into the eye to widen the pupil and allow the optometrist to see the inner structures of the eye in greater detail.
Ultrasound: An ultrasound is a type of imaging test that uses high-frequency sound waves to take a picture of the inner structures of the body, according to the Victorian Government's Better Health Channel. An ultrasound may be used to examine the inside of the eye and help diagnose possible ocular melanoma.
Biopsy: A biopsy is a procedure in which a small sample of tissue is removed from the body and taken for examination under a microscope. A biopsy may be used to help diagnose ocular melanoma if other tests have not been conclusive, or if a healthcare professional needs more information about a possible tumour.

How Serious is Ocular Melanoma?

Ocular melanoma is a very serious eye condition that should be assessed, monitored and treated by a healthcare professional. Ocular melanoma can lead to vision loss and, according to the Mayo Clinic, can lead to complications such as a retinal detachment which can also result in vision loss. While ocular melanoma is a rare type of cancer, according to the American Academy of Ophthalmology, it is the most common eye cancer in adults. It is important to book regular eye tests as it may detect if a person has ocular melanoma and the eye care professional can proceed with treatment accordingly. It is recommended everyone should have an eye test with an optometrist at least once every two years, and once a year if they are over the age of 65.

Can Ocular Melanoma Spread to Other Parts of the Body?

Yes, ocular melanoma can potentially spread to other parts of the body. According to the Mayo Clinic, it is possible for ocular melanoma to spread (metastasize) outside the eye to other areas of the body such as the lungs, bones and most often to the liver. While this type of cancer can spread in the body, according to NORD, the National Organisation for Rare Disorders, it is extremely rare for ocular melanoma to spread to the skin and also rare for skin cancer to spread to the eye.

What are the Treatments for Ocular Melanoma?

The most common treatments for ocular melanoma include eye surgery, photocoagulation, radiation therapy, targeted therapy, thermotherapy, active surveillance or watchful waiting and immunotherapy. Treating cancer, including ocular melanoma, can typically involve different types of doctors or specialists in order to combine different treatments for a comprehensive treatment plan according to the American Society of Oncology. Treatment for ocular melanoma is also determined by the location of the melanoma and what stage it is at. The treatments for ocular melanoma and their definitions are listed below.

Eye Surgery: Eye surgery can be used to treat ocular melanoma which involves removing the melanoma as well as some of the surrounding healthy tissue.
Photocoagulation: Photocoagulation involves using laser light to remove the blood vessels that deliver nutrients to the melanoma in order for the melanoma cells to die.
Radiation Therapy: Radiation therapy uses radiation in either internal or external forms to eliminate cancer cells or prevent their growth.
Targeted Therapy: Targeted therapy utilises drugs to target specific features of cancer cells to hinder the growth and spread of melanoma tumours.
Thermotherapy: Thermotherapy, specifically transpupillary thermotherapy, can be used to help kill cancerous cells by using heat or cold.
Active Surveillance or Watchful Waiting: Active surveillance, also known as watchful waiting, is a type of treatment for ocular melanoma that involves actively monitoring a melanoma with regular eye tests and checkups, instead of treating it straight away, with the aim of avoiding side effects from treatment like radiation. Active surveillance is only used on melanoma that is small, slow growing and causing no symptoms.
Immunotherapy: Immunotherapy is a type of cancer treatment that can be used to treat ocular melanoma and involves encouraging the immune system to detect cancerous cells and kill them.

1. Eye Surgery

Eye surgery for ocular melanoma can include different types of surgical procedures such as resection, enucleation and exenteration according to the National Cancer Institute. Resection involves removing the melanoma tumour and a portion of the healthy tissue around it. Enucleation may be used if the tumour is too large, has reached the optic nerve or vision cannot be retained and involves removing the eye and some of the optic nerve. The patient will require an artificial eye post-surgery. Exenteration is another type of surgery that removes the contents within the eye’s orbital area including the eyelid, eye, nerves, fat and muscles. The risks involved in performing surgery on the eye can include loss of partial or total vision in the operated eye and enucleation and exenteration immediately cause total loss of vision.

2. Photocoagulation

Photocoagulation is a procedure that involves using laser light to remove or shrink the blood vessels that are delivering nutrients to the melanoma. Photocoagulation therapy, also known as laser photocoagulation, is a non-surgical method of treating cancerous melanoma. It has commonly involved krypton laser, xenon-arc laser, and argon laser and has been used to treat melanoma tumours that are small and are normally found in the posterior choroid according to Abhilasha Maheshwari and Paul T. Finger in their article published in the Survey of Ophthalmology. The risks associated with this treatment are loss of vision, however, this depends on the location and size of the melanoma, according to the American Cancer Society.

3. Radiation Therapy

Radiation therapy may be used as a treatment for small and medium-sized ocular melanomas which involves eliminating cancer cells or preventing them from growing. The two types of radiation therapy are external and internal radiation. According to the National Cancer Institute, external radiation is performed by using a machine to target the radiation towards the tumour. This method can prevent the radiation from harming the surrounding healthy tissue. Types of external radiation therapy include charged-particle external beam radiation therapy and gamma knife therapy. Internal radiation therapy can involve radioactive plaque therapy and brachytherapy, which may be conducted by placing the radioactive material in catheters, seeds, wires or needles and are either inserted into or placed near the tumour. Immediate side effects of using radiation therapy may include causing damage to the eyes which may result in cataracts, retinal detachment, blurry vision, increased eye pressure, tear duct issues and bleeding in the eye according to the American Cancer Society. Radiation therapy has been found to be an effective treatment for 9 out of 10 melanoma tumours small to medium-sized according to the American Cancer Society.

4. Targeted Therapy

Targeted therapy is a treatment used for melanoma tumours on a molecular level. Targeted therapy works by interfering with molecules that are specifically targeted and consequently stopping the growth of cancer cells. The two types of targeted therapy are small-molecule drugs and monoclonal antibodies according to the National Cancer Institute. The common risks that may be involved with this type of treatment for ocular melanoma are floaters, blurry vision, vision loss, eye pain and redness according to the National Institutes of Health.

5. Thermotherapy

Thermotherapy is a type of treatment that may be used to help treat melanoma through the use of heat or cold, according to the National Library of Medicine. It can be used for many different conditions such as osteoarthritis and other muscle-related pain. According to the Cancer Council, transpupillary thermotherapy is a type of laser treatment for ocular melanoma which uses an infrared laser to destroy cancer cells through heat.

6. Active Surveillance or Watchful Waiting

Active surveillance, sometimes called watchful waiting, is a type of cancer treatment that may be used for those with ocular melanoma who have a small tumour that is not growing and are without symptoms. Active surveillance involves actively and regularly monitoring and testing a melanoma for being a cancerous tumour instead of treating it immediately. According to the Canadian Cancer Society, active surveillance is used as a way to avoid negative side effects from other treatments including radiation therapy.

7. Immunotherapy

Immunotherapy is a type of cancer treatment used to treat ocular melanoma. According to the American Cancer Society, immunotherapy works by stimulating a person’s immune system so that it recognises the cancer cells and attacks them more effectively. A new type of immunotherapy drug that may be used to treat ocular melanoma is called KIMMTRAK (tebentafusp), a bispecific fusion protein, which is injected into the body via an IV infusion. Side effects of this immunotherapy drug include fever, swelling of the skin, skin rash and redness,nausea and vomiting. According to an article published by the National Cancer Institute in 2021, tebentafusp has improved the survival rate for advanced uveal melanoma.

How Treatable is Melanoma of the Eye?

Treating melanoma of the eye is dependent on two key factors, the location and its size. Another important consideration, according to the American Cancer Society, is the probability of saving the person’s eyesight. The treatment plan for ocular melanoma is determined based on each person’s situation and will be discussed with their eye doctor to determine what is most important to them. The treatments available for melanoma of the eye include eye surgery, thermotherapy, immunotherapy, radiation therapy and photocoagulation.

What is the New Treatment for Ocular Melanoma?

According to an article published by the Melanoma Research Alliance in July 2022, KIMMTRAK is a new treatment for ocular melanoma which has been approved by the American Food and Drug Administration or FDA. KIMMTRAK treats ocular melanoma by helping a person’s immune cells get close to and attack the melanoma cells. This therapy is also being trialled to treat other conditions such as infectious and autoimmune diseases. KIMMTRAK, also known as tebentafusp, is administered through an IV infusion and is typically administered weekly.

Can Eye Drops be Used in Treating Ocular Melanoma?

Yes, eye drops may be used to treat certain types of ocular melanoma. According to Cancer Research UK, chemotherapy eye drops may be prescribed by an eye doctor to treat cancer on the surface of the eye, such as the conjunctiva. This type of treatment is known as topical chemotherapy and may cause side effects such as inflammation, watery eyes and redness.

What are Ways to Prevent Ocular Melanoma?

While ocular melanoma is not exactly preventable, there are certain ways a person can reduce their risk of developing this condition and increase the chances of early detection. The ways to possibly prevent ocular melanoma include having regular eye tests and wearing sunglasses. These two ways to possibly prevent ocular melanoma and their definitions are listed below.

Have a regular eye test: Booking a regular eye test is crucial in maintaining the health of your eyes as an optometrist can detect, diagnose and monitor certain eye conditions and diseases including ocular melanoma. Regular eye tests can also help to detect certain abnormal growths & lesions on the eye which may increase the risk of ocular melanoma.
Wear sunglasses: Wearing sunglasses can protect the eyes from harmful UV rays emitted from the sun. The American Cancer Society also recommends people should wear sunglasses when outside as it may reduce their risk of developing skin cancer around the eyes.

Image of a person wearing sunglasses in the sun.

Can Wearing Eye Glasses Help Prevent Ocular Melanoma?

No, wearing optical eye glasses will not help prevent ocular melanoma as, according to the American Cancer Society, it is difficult to prevent ocular melanoma as the cause of most eye cancers is not yet known. However, wearing sunglasses may reduce a person’s risk of developing skin cancer around the eye by protecting the eyes from harmful UV rays. Glasses are worn to correct a person’s vision, typically refractive errors such as nearsightedness, farsightedness and astigmatism.