Eye cancer occurs when cancerous cells develop in the tissues of the eyes. In most cases the malignant tumor is secondary to cancers that have spread by metastasis. There are two types of eye cancer: retinoblastoma and melanoma. Retinoblastoma affects mostly children aged less than five years, whereas melanoma is more prevalent among adults. Although malignancy of the eye is rare, it is particularly serious because it sometimes requires impressive surgery.
The eye extends back through the optic nerves. Seven muscles allow mobility and a field of fairly wide vision. Nerves, artery, vein and fat fill the hollow of the orbit (the cavity of the skull in which the eye and its appendages are located). Lacrimal glands, on top and the outer side of the orbit; eyelids and skin are also included.
If a tumor grows in the eye, it may then compress these elements. Located at the back of the orbit, it will push the eye forward. The tumor can also compress the optic nerve and disrupt vision, causing the patient to have double vision ( diplopia) or worse. These are the main signs but more often, there are none, which delays the diagnosis of the cancer.
Eye Cancer Causes and Risk factors
Genetic predisposition is the first risk of developing melanoma, followed by prolonged sun and certain industrial chemicals such as polychlorinated biphenyls (PCBs) exposures. People who have very light skin seem to be more at risk to have the disease. However, in most cases, cancers of the eye are called secondary cancers because they are other cancer metastases which have spread to the eye tissue.
Melanoma and retinoblastoma
Malignant melanoma arises from cancerous cells that develop in the tissues of the eye: iris, choroid and ocular muscles. Retinoblastoma, however, develops in the retina. The disease may be bilateral or affects one of the two eyes, depending on the severity or stage of the cancer.
Eye Melanoma Symptoms
Some of the eye melanoma symptoms and signs include:
- Light Flashes
- Gradual loss of vision
- Redness of the eyes
- Appearance of spots in the visual field
- Convergence of the eyes
- outgrowth on the surface of the eye.
If you or your child has any of these symptoms, it is best to consult an ophthalmologist as soon as possible to avoid complications. The physician will conduct a clinical eye examination and a dilatation of the pupil to confirm or rule the cancer. If tumor is suspected, ocular ultrasound, scanner or an MRI will determine the location of the disease and its characteristics.
Eye Retinoblastoma Symptoms
Eye retinoblastoma symptoms may not be similar to those of melanoma. The most easily recognizable of retinoblastoma symptoms are strabismus and leukocoria. The latter refers to a white pupil (or white reflection) visible in certain lights, flash of a camera for instance. These symptoms are indications that say you must quickly see a medical specialist.
Early diagnosis and appropriate treatment can limit damage to the eye. Thus, experts believe that if they are started early enough, current treatments can cure 95% of children suffering from eye cancer. That is why it is important in a family with history of retinoblastoma cases the child must be examined in the first months after birth by an ophthalmologist.
Eye Cancer Treatment
The radiation in destroys cancer cells while preserving the healthy ones and the vision of the patient; it is often used in the treatment of eye melanomas and retinoblastoma. Laser treatment is also used for small tumors. Cryotherapy is itself a technique to destroy cancer cells by freezing. But it is not often used to treat eye cancer.
Surgery is reserved for very advanced or big tumors that cannot be treated by conservative treatment. It is based on enucleation, removal of the eyeball while leaving the eye muscles and remaining orbital contents intact. Finally, in case of risk of metastasis, chemotherapy is sometimes given: this prevents the eye cancer from spreading to other body tissues. But it is not a curative treatment.