Description:
There are a number of different types of cancer that affect the eyes, including:
*eye melanoma
*squamous cell carcinoma
*lymphoma
*retinoblastoma – a childhood cancer
Cancer can also sometimes develop in the tissues surrounding your eyeball or spread to the eye from other parts of the body, such as the lungs or breasts.
This topic focuses on melanoma of the eye, one of the most common types of eye cancer. The Cancer Research UK website has more information about other types of eye cancer.
Symtoms:
Eye cancer doesn’t always cause obvious symptoms and may only be picked up during a routine eye test.
Symptoms of eye cancer can include:
*shadows, flashes of light, or wiggly lines in your vision
*blurred vision
*a dark patch in your eye that’s getting bigger
*partial or total loss of vision
*bulging of one eye
*a lump on your eyelid or in your eye that’s increasing in size
*pain in or around your eye, although this is rare
These symptoms can also be caused by more minor eye conditions, so they’re not necessarily a sign of cancer. However, it’s important to get the symptoms checked by a doctor as soon as possible.
Causes:
The exact cause of most eye cancers is not known. But scientists have found that the disease is linked with some other conditions, which are described in Risk Factors for Eye Cancer. A great deal of research is being done to learn more about the causes.
Scientists are learning how certain changes in the DNA inside cells can cause the cells to become cancer. DNA is the chemical in each of our cells that makes up our genes, the instructions for how our cells function. We usually look like our parents because they are the source of our DNA. But DNA can also influence our risk for developing certain diseases, such as some kinds of cancer.
Some genes control when our cells grow, divide into new cells, and die.
*Genes that help cells grow, divide, or stay alive are called oncogenes.
*Genes that slow down cell division or cause cells to die at the right time are called tumor suppressor genes.
Cancers can be caused by DNA changes that turn on oncogenes or turn off tumor suppressor genes.
Some people with cancer have DNA changes they inherited from a parent that increase their risk for the disease. For example, some people inherit a mutation (change) in the BAP1 tumor suppressor gene, which raises their risk of eye melanoma and some other cancers. When the BAP1 gene is mutated, it doesn’t work normally, which can allow cells with this change to grow out of control.
Most DNA changes linked to cancer are acquired during a person’s life rather than inherited before birth. For example, about half of uveal eye melanomas have changes in either of 2 related oncogenes, GNA11 or GNAQ.
Scientists are studying these and other DNA changes to learn more about them and how they might lead to eye cancer. But it is still not exactly clear what causes these changes to occur in some people and not others.
Risk factors:
*Light eye color. People with blue eyes or green eyes have a greater risk of melanoma of the eye.
*Being white. White people have a greater risk of eye melanoma than do people of other races.
*Age. …
*Certain inherited skin disorders. …
*Exposure to ultraviolet (UV) light. …
*Certain genetic mutations.
Diagnosis:
For most types of cancer, the diagnosis is made by removing a small piece of the tumor and looking at it in the lab for cancer cells. This is known as a biopsy.
A biopsy is often not needed to diagnose eye melanomas because almost all cases can be accurately diagnosed by the eye exam and imaging tests. Sometimes, a biopsy may be useful to check for certain gene mutations (changes) that can predict outcomes (prognosis) as well as help choose targeted drugs for your cancer. Also, certain eye melanomas can spread for many years before they are diagnosed so doing a biopsy of a worrisome area early may be helpful.
If a biopsy is needed, it can be done either with sedation and local anesthesia (numbing medicine) or while a person is under general anesthesia (in a deep sleep). Different types of biopsies can be done for eye melanoma depending on where it is located including:
A FNA (fine needle aspiration): Using a thin needle to remove a small sample of aqueous humor (the liquid between the cornea and the lens)
An incisional or excisional biopsy (cutting out either part of or all of the tumor)
A fine needle biopsy of the tumor: Cells from the tumor are sucked up into a syringe through a small needle and examined in the lab.
Newer techniques help to lower the chances of tumor cells leaking and spreading along the needle path during these biopsies so the cancer doesn’t spread within or outside the eye.
While most people with melanoma of the eye are treated without having a biopsy first, your doctor may recommend a biopsy depending on your specific situation. They can discuss the risks and benefits of the procedure they feel is best for you. Some doctors have started using biopsies to get a sample of the tumor for gene testing (DecisionDx-UM). They have found that certain patterns of genes in tumor cells are a good way to tell if an eye melanoma is likely to spread. Based on these gene patterns, a little more than half of eye melanomas are shown to be Class 1 (1A or 1B) tumors which have a low risk of spreading. The remaining eye melanomas fall into the Class 2 category, which have a very high risk of spreading. See What’s New in Eye Cancer Research? for more information.
Liquid biopsy
A new type of biopsy called a liquid biopsy is being looked at more often. Instead of having to make a cut or put a needle into the eye, melanoma tumor cells can be collected from a blood sample. These cancer cells can then be tested for certain traits, including genetic changes, that can help predict how likely the cancer is to spread or come back after treatment.. Liquid biopsies might help diagnose tumor spread earlier, or help the doctors know if treatment is working. This could be very helpful in people who did not have a biopsy of the tumor and want to preserve their vision. However, the equipment needed for this test is not readily available so this type of biopsy is not done routinely and is mainly done as part of a clinical trial.
Blood tests
Blood tests can’t be used to diagnose melanoma of the eye, but they may be done once a diagnosis is made.
Liver function tests:
If you have been diagnosed with eye melanoma, your doctor may order blood tests to see how well your liver is working. Abnormal test results can sometimes be a sign that the cancer has spread to the liver.
Staging:
A staging system is a standard way to describe how far a cancer has spread. The most common systems used to describe the stages of eye cancer are the American Joint Committee on Cancer (AJCC) TNM system and the Collaborative Ocular Melanoma Study (COMS) group classification system.
The AJCC TNM system is based on three key pieces of information:9
*The size and extent of the main tumor (T)
*The spread to nearby lymph nodes (N)
*The spread (metastasis) to distant sites (M)
The staging system devised by the COMS group is simpler, and divides eye melanomas into small, medium, and large:
*Small: Between 1 mm and 3 mm in height and between 5 mm and 16 mm across
*Medium: Between 3.1 mm and 8 mm in height and no more than 16 mm across
*Large: More than 8 mm in height or more than 16 mm across
Treatment:
Treatments for eye cancer depend a lot on the size and stage of your cancer, where it is located, and how fast the cancer is growing. Some cancers grow very slowly and rarely spread. In these cases, your healthcare provider may choose to monitor the cancer closely without performing any invasive procedures.
When more significant treatment is needed, options include:
*Surgery can remove small parts of, or even the entire eye10
*Radiation therapy using implanted seeds or external radiation beams can target and destroy cancer cells11
*Laser therapy using infrared beams can heat or burn cancerous tissue12
*Chemotherapy is not often used in eye cancers unless it has spread to other parts of the body13
*Immunotherapy and other targeted treatments have become very effective at training the immune system or managing genetic mutations to fight eye cancers14
The focus of treatment is on preserving vision, so a small cancer that is already impacting vision could lead to complete removal of the eye. In other cases, a large area of cancer that is not impacting vision may be treated without removing the eye. Treatment choices should be a shared decision between you and your healthcare provider.
Prevention:
ACS recommends limiting exposure to intense sunlight, wearing protective clothing and hats in the sun, using sunscreen and wearing wraparound sunglasses with 99 percent to 100 percent UVA and UVB absorption to protect the eyes and the skin around the eyes.
Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.
Resources:
https://www.nhsinform.scot/illnesses-and-conditions/cancer/cancer-types-in-adults/eye-cancer/
https://www.cancer.org/cancer/eye-cancer/causes-risks-prevention/what-causes.html
https://www.cancer.org/cancer/eye-cancer/detection-diagnosis-staging/tests.html#:~:text=For%20most%20types%20of%20cancer,eye%20exam%20and%20imaging%20tests.https://www.verywellhealth.com/eye-cancer-5095588
