Melanoma is a form of skin cancer that affects melanocytes or the cells that produce melanin which gives color to the skin. Similar to the skin, the eyes also contain melanocytes which can, later on, develop melanoma. Eye melanoma is also known as ocular melanoma.
Ocular melanoma can be difficult to detect because it develops primarily in the unseen part of the eye and usually does not cause early signs and symptoms. Fortunately, treatment for minor eye melanomas commonly does not interfere with vision. However, treatment for severe eye melanomas can cause some loss of vision.
Ocular melanoma symptoms may include:
- growing dark spot on the conjunctiva or the iris
- seeing flashes or specks of dust in the visual field (floaters)
- a shift in the pupil shape
- decreased or blurry vision in one eye
- poor peripheral vision
Doctors believe that ocular melanoma occurs when the DNA of healthy cells start to develop abnormalities. These DNA abnormalities cause melanocytes to grow rapidly and out of control. These become mutated cells and accumulate in the eye, causing eye melanoma.
Where Does Ocular Melanoma Exactly Occur?
Ocular melanoma usually develops in the uvea which contains three parts:
Iris – the colored part of the eye
Choroid layer – a layer between the sclera and retina at the back of the uvea
Ciliary body – located in front of the eye and produces the transparent liquid of the eye or the aqueous humor.
Ocular melanoma, although very rare, can also occur on the conjunctiva, eyelid, or in the socket surrounding the eyeball.
Who Is at Most Risk?
Risk factors for eye melanoma include:
- Some inherited skin conditions. People with dysplastic nevus syndrome, abnormal skin pigmentation, or other inherited skin disorders may have an increased risk of developing eye melanoma.
- Light eye color. People with light colors of the eye such as blue or green may have greater risks.
- Exposure to UV light. UV light from the sun or tanning beds is believed to contribute to the development of eye melanoma.
- Age. As a person ages, the risk of eye melanoma also increases.
Complications of Eye Melanoma
Complications may include:
- Glaucoma. Growing eye melanoma may cause increased eye pressure or glaucoma with symptoms of eye pain, redness, and blurry vision.
- Vision loss. Large and severe eye melanomas commonly cause vision loss or retinal detachment in the affected eye. Small eye melanomas can also cause some vision loss if they are located in critical parts of the eye.
- Metastasis. Eye melanoma can spread systemically in the body which can affect parts outside the eye such as the lungs, liver, and bones.