What Is Eye Melanoma? Symptoms and Treatment

Melanoma is a type of skin cancer developing in the skin’s melanin-producing cells called nevi and melanocytes. Our eyes also contain melanin-producing cells and, although very rarely, can develop melanoma. Eye melanoma is also called ocular or uveal melanoma.

• Most eye melanomas cannot be noticed by looking in a mirror. This makes them difficult to detect. Eye melanoma also generally causes no early symptoms. 
• Nevertheless, eye melanoma can be treated. Treatment of small eye melanomas does not affect vision. Treating large eye melanomas, however, may cause some vision loss.
• Eye melanoma is classified among rare cancers .

What are the symptoms of eye melanoma?

Eye melanoma may cause no signs or symptoms. When symptoms do occur, they may include: 

• A growing dark spot on the iris
• Sensitivity to flashing lights
• A change in the shape of the pupil at the center of the eye
• Reduced or blurred vision in one eye
• Loss of peripheral vision (at the edges of the visual field) 
• Sensitivity to bright light and a dusty sensation in vision.

When should you see a doctor?

If you experience any of these signs and are concerned, or have sudden changes in vision, you should be examined by a specialist ophthalmologist.

What risk factors increase the likelihood of eye melanoma?

• Eye melanoma, also called ocular melanoma, can occur at any age, but the median age at occurrence is 55.
• The exact cause of eye melanoma is unknown, but like all other cancers, melanoma results from damage to cellular DNA . Accumulating DNA damage prevents the cell from undergoing programmed cell death (apoptosis), and uncontrolled proliferation begins.
• Light-colored eyes. People with blue or green eyes have a higher risk of developing eye melanoma.
• Fair skin. People of racial backgrounds with lighter skin are at higher risk than those of other racial backgrounds.
• Certain inherited skin disorders. Dysplastic nevus syndrome, a condition causing abnormal moles, can increase the risk of melanoma in the skin and eyes. People with certain conditions causing abnormal skin pigmentation, such as melanocytosis, also have an increased risk of eye melanoma.
• Exposure to ultraviolet (UV) rays. Exposure of the eyes to UV rays from sources such as sunlight or tanning beds increases melanoma risk.

Where does eye melanoma develop?

Eye melanoma most commonly develops in the middle layer of the eye, the uvea [in its front part (iris and ciliary body) or back part (choroid layer)].

Eye melanoma can also occur around the eye (conjunctiva), in the outermost layer and in the eyelid, but these forms are much rarer.

What problems can eye melanoma cause (complications)?

• Increased pressure in the eye (glaucoma). An enlarging eye melanoma can cause glaucoma. Signs and symptoms may include eye pain, redness and blurred vision.
• Vision loss. Large eye melanomas can often cause vision loss through problems such as retinal detachment. Small melanomas may also impair vision if they affect a critical area of the eye. Very advanced eye melanomas may cause complete vision loss. 
• Eye melanoma spreading outside the eye. It can spread outside the eye and to distant parts of the body, including the liver, lungs and bones.

How is eye melanoma treated?

Treatment selection is mainly based on tumor size. Under a system recommended by the Collaborative Ocular Melanoma Study, eye melanoma is classified as small, medium or large according to tumor size.

Treatment options for ocular melanoma include:

Radiotherapy

Radiotherapy uses high-energy X-rays to kill cancer cells. Compared with surgery, radiotherapy may better preserve the eye’s appearance.

Types of radiation therapy include:

• Brachytherapy (internal radiotherapy): Material containing radioactive seeds is surgically placed in and around the tumor and left in place for 4-7 days.
• External beam radiotherapy: High-energy radioactive rays are focused on cancer from outside the body (conventional radiotherapy).

Possible side effects include inflammation of the eyelids and, from damage within the eye, cataracts, retinal detachment, glaucoma or bleeding inside the eye.

Eye melanoma surgery

Surgical options include:

• Tumor resection (complete or partial removal)
• Enucleation (removal of the entire eyeball, followed by an orbital implant to replace it)

Surgical complications include anesthetic complications (from the anesthetic drug used), bleeding and infections.

Treatment options for spread (metastatic) disease include:

• Chemotherapy: Use of cell-killing (cytotoxic) drugs to kill cancer cells.
• Immunotherapy: Use of drugs that activate the immune system against cancer. Immunotherapies have become the most effective and most widely used drugs for metastatic melanomas today.
• Stage 4 melanoma most commonly metastasizes to the liver. To treat liver metastases, chemotherapy, immunotherapeutic agents or radioactive beads may be delivered into the liver through an artery.

After treatment, regular follow-up is necessary to check for possible recurrence or spread.

Related Topic:

- The relationship between UV rays and cancer