Ocular Melanoma: Signs & Symptoms of Eye Cancer

Ocular melanoma is very rare (about 5 cases are diagnosed per million individuals). However, it is the most common type of eye cancer. Certain factors like lighter-colored eyes are a risk factor for ocular melanoma. Please continue reading to learn about the other risk factors for developing eye melanoma, the signs and symptoms of ocular melanoma, and treatment options.

What is an ocular melanoma?

An ocular melanoma is a type of eye cancer that develops in the melanin-producing cells called melanocytes, which produce pigment. Melanin is a pigment that gives color to our eyes, skin, and hair. You may have heard of a skin melanoma that can develop in abnormal moles, especially in people with fair skin. Just like you can develop melanoma (skin cancer) from the uncontrolled growth of melanocytes (cancerous cells) in the skin, you can develop ocular melanoma from the uncontrolled growth of melanocytes in the eye.

It is unclear what exactly triggers the formation of ocular melanomas. But we do know that an ocular melanoma occurs due to mutations (errors) in the DNA of melanocytes (pigment cells). The mutated cells multiply out of control and form ocular melanomas.

Most eye melanomas form in the middle layer of the eye called the uvea, between the outer layer (sclera) and the inner layer (retina). Uveal melanomas can be anterior uveal melanomas that occur in the iris (colored part of the eye) or posterior uveal melanomas that occur in the choroid (choroidal melanoma) or ciliary body. Less commonly, ocular melanomas can develop in the conjunctiva.

Who is at risk of developing ocular melanoma?

Risk factors for developing melanoma in the eye include:

Growths (nevi or moles) in the eye or on the surface of the eye.
Abnormal skin pigmentation involving the eyelids.
Increased uveal pigmentation.
Light-colored eyes (blue or green).
Older age.
Caucasian ethnicity.
Long-term exposure to UV light from sunlight or tanning beds (a risk factor for conjunctival melanoma).
Inherited skin conditions such as dysplastic nevus syndrome (also called atypical mole syndrome).

What are the first signs of eye cancer?

Ocular cancers frequently develop inside your eye (in a part of your eye that is not visible to you if you look in a mirror). Additionally, an early-stage ocular tumor may not cause any symptoms. Therefore, there may be no early signs, and you may not know you have an ocular melanoma. The tumor may be detected on a routine eye examination. When symptoms of ocular melanoma are present, they can include:

A visible dark spot on your iris or conjunctiva
Blurred vision or double vision in the affected eye
Scotoma (blind spot) in your side vision
Floaters (specks, flecks, strings, or cobwebs in your vision)
A sensation of flashing lights
Changes in the shape of your pupil
Painless and progressive loss of visual field (losing an area of vision)
Severe eye pain
Systemic symptoms like weight loss and fatigue

Note: Eye melanomas form in melanocytes in the eye. Sometimes, a primary tumor that develops in another part of the body (for example, breast cancer or lung cancer) can spread to the eye if the cancer cells travel to the eye through the blood vessels. These tumor deposits are called eye metastasis.

What is the first stage of eye melanoma?

Eye melanomas are staged according to the TNM system, which takes into account the size of the tumor (T), whether it has invaded other parts of the eye or nearby tissues such as lymph nodes (N), and whether it has spread (metastasized) to other parts of the body (M). T1 tumors are the smallest, and T4 tumors are the largest. N0 tumors are those where the cancer cells have not spread to nearby lymph nodes, and N1 tumors are those where the cancer has spread to nearby structures. M0 tumors are those where the cancer cells have not spread to other parts of the body, and M1 tumors are those where it has spread to distant parts. An early-stage eye melanoma (T1N0M0) may not cause any symptoms and may be discovered only on a routine eye exam.

How quickly does melanoma of the eye spread?

How quickly a melanoma of the eye spreads depends on various factors. The spread of an eye melanoma can occur within 2-3 years of diagnosis or decades later, depending on the aggressiveness of the tumor. Eye melanoma typically spreads to the liver, but it can also spread to the lungs, bone, and skin. Metastasis occurs in approximately 40-50% of people with ocular melanoma. Metastasis is associated with a high mortality rate because it can be difficult to eradicate all the metastases (tumor deposits) in different parts of the body. The risk of developing a metastatic uveal melanoma can be correlated to the location where the eye melanoma occurs. An iris melanoma has a low rate of metastasis. Choroidal and ciliary body melanomas have a greater risk of the cancer spreading.

How do eye doctors diagnose eye melanoma?

Eye melanomas are often detected on routine eye exams. If your eye doctor suspects an ocular melanoma, they may order further testing with an ultrasound exam of the eye, fluorescein angiography, fundus autofluorescence, optical coherence tomography, and a biopsy.

What is the treatment for ocular melanoma?

Treatment options for ocular melanoma depend on the size and location of the tumor and your general health status.

Radiation therapy

Your health care team may recommend radiation therapy to destroy cancer cells. This is usually done with plaque therapy in which radioactive seeds in a gold plaque (disk) are placed directly near the tumor for 4-5 days. Radiation therapy for eye melanoma can also be delivered through a beam of radioactive particles and for smaller tumors, through laser or heat energy.

Surgery

Your eye doctor may recommend surgically removing the eye melanoma along with a small amount of surrounding healthy tissue. Some larger tumors that cause eye pain or involve the optic nerve may require enucleation (removal of the entire eye). In such cases, an implant is left in place, and after you heal from the surgery, you can be fitted with a prosthesis (artificial eye) that matches your remaining eye.

Treatment for conjunctival melanoma

This type of eye melanoma is located on the surface of the eye. The treatment may include chemotherapy eye drops, freezing, radiation, and/or surgery.Note: Treatments for eye melanoma can result in blurry vision or loss of vision. Your eye doctor will discuss options to help you deal with any vision loss.

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