Melanomais an aggressive form of skin cancer that can be life-threatening. Melanoma typically affects the skin, but it can also spread to the eye.
Malignant melanoma of the eye is a rare condition that can occur when the eye has been exposed to too much ultraviolet radiation, or sunlight. The choroid layer of the eye is where the blood vessels are stored. This is the layer most commonly affected by malignant melanoma.
The disease can also affect other structures of the eye, including the:
- ciliary body, which helps lubricate the eye and contains muscles that help the eye focus
- conjunctiva, which is a thin, transparent tissue that covers the inside of the eyelid and the sclera, or the white of the eye
- iris, the colored part of the eye that helps control how much light is let in
- orbit, the cavity in the skull that contains the eye
Although melanoma of the eye is rare, it’s the most common type of eye cancer in adults. People with fair skin or blue eyes are most affected by this type of cancer. This type of cancer can also spread to other parts of the body, usually the liver.
Many people with primary malignant melanoma have no symptoms. The condition is often found during a routine eye exam. The symptoms can be quite distinct in those who do develop them. They can include:
- bulging eyes
- changes in the color of the iris
- vision changes, such as blurred vision or double vision
- red, swollen eyes and pain in the eyes, or both
- small defects that can be seen on the iris or conjunctiva
Malignant melanoma of the eye can develop when pigment cells found in the eye grow out of control. Pigment cells are responsible for your eye color. The cause of uncontrollable cell growth isn’t usually known. Exposure to ultraviolet radiation has been identified as one potential cause of the disease.
Malignant melanoma that begins in the eye is known as a primary tumor. This type of cancer can occur at any age, but it’s more common in people over the age of 55. This type of cancer affects men and women equally.
Malignant melanoma may result if cancer that develops in another part of the body metastasizes. Metastasis occurs when cancer from one organ or part of the body grows and spreads to another. Metastasis of liver cancer may lead to malignant melanoma. If melanoma develops because of metastasis, it’s considered a secondary tumor.
Malignant melanoma of the eye is usually diagnosed through an examination of the eye using an ophthalmoscope. An ophthalmoscope is a device that enables your doctor to see and examine the structures of the eye. If your doctor detects a tumor in the eye, additional tests may be ordered to confirm diagnosis. These can include:
- a CT scan to check for metastasis to the brain
- an ultrasound of the eye
- an MRI of the head and brain
- a skin biopsy
Treatment for malignant melanoma of the eye will depend on the specific type of tumor that you have. If the tumor is small and isn’t growing rapidly, your doctor may not recommend any treatment. Instead, your doctor will monitor your tumor to make sure that it doesn’t grow, spread, or change.
Your doctor may recommend more aggressive treatment if your tumor is large or has the potential to spread to other organs in the body. Malignant melanoma of the eye can be life-threatening if it spreads to other organs.
The goal of treatment is to limit the growth of the tumor and prevent it from spreading. This can be accomplished through the following treatments:
- surgery to remove the eye
- radiation therapy to kill the cancer cells inside the eye
- irradiation therapy that delivers beams of X-rays to kill cancer cells in the eye
- laser therapy
The type of tumor determines the outlook for a person with malignant melanoma of the eye. The outlook is quite good if the malignant melanoma is a primary tumor and hasn’t spread to other parts of the body.
With appropriate treatment, a majority of people will survive at least five years after diagnosis. However, treatment for malignant melanoma of the eye may result in vision loss or damage to the eye. In some cases, removal of the eye may be necessary.
For people with secondary malignant melanoma of the eye or a primary tumor that spreads to other organs in the body, the outlook isn’t as favorable. Survival rates decline significantly depending on the additional organs that are affected by the cancer.
Secondary malignant melanoma of the eye often results from liver cancer. Five-year survival rates for liver cancer are approximately 15 percent.
You can help prevent malignant melanoma of the eye by getting an annual eye exam. Avoiding excessive exposure to sunlight is also helpful. Sunglasses with ultraviolet protection should be worn when the sun’s rays are the strongest, which is between 10 a.m. and 2 p.m.