Eye Cancer: Overview
Eye cancer is a general term used to describe many types of tumors that can start in various parts of the eye. It occurs when healthy cells in or around the eye change and grow uncontrollably, forming a mass called a tumor. A tumor can be benign or cancerous. A benign tumor means the tumor can grow but will not spread. A cancerous tumor is malignant, meaning it can grow and spread to other parts of the body. Cancer that forms in the eyeball is called an intraocular (inside the eye) malignancy.
Parts of the eye
The eye is the organ that collects light and sends messages to the brain to form a picture. The three main parts of the eye are:
- Eyeball
- Orbit (eye socket)
- Adnexal (accessory) structures, such as the eyelid and tear glands
The outer part of the eye is made up of the sclera, retina, and uvea. The sclera is the outer wall of the eyeball. The retina is a thin-layered structure that lines the eyeball and sends information from the eye to the brain. The uvea nourishes the eye. Both the retina and the uvea contain blood vessels.
The uvea consists of the following:
- Iris: The colored part of the eye that controls the amount of light entering the eye
- Ciliary body: Muscular tissue that produces the watery fluid in the eye and helps the eye focus
- Choroid: The layer of tissue underneath the retina that contains connective tissue and melanocytes, which are pigmented (colored) cells, and nourishes the inside of the eye. The choroid is the most common site for a tumor.
Types of intra ocular cancer
The most common intra ocular cancer in adults is uveal metastases, which is cancer that has spread to the uvea from another place in the body. This is called secondary cancer. This guide is about primary intra ocular cancer, meaning that the tumor started in the eye, not somewhere else in the body.
Melanoma is the most common type of primary intra ocular cancer in adults. It begins when cells called melanocytes grow uncontrollably. Intra ocular melanoma is also called uveal melanoma.
Other, less common types of an intra ocular tumor include:
- Intra ocular lymphoma is lymphoma that begins in the eyeball. This condition is rare and can be difficult for doctors to diagnose. Many doctors consider intra ocular lymphoma to be a type of central nervous system lymphoma. Most intra ocular lymphomas are non-Hodgkin lymphoma.
- Retinoblastoma is a rare form of childhood eye cancer.
- Hemangioma is a benign tumor of the choroid and retina that starts in the blood vessels.
Other, rare cancers of the eye include:
- Conjunctival melanoma is a tumor of the conjunctiva, which is a membrane that lines the eyelid and eyeball. If it is not treated, it can spread to the lymph nodes, which are tiny, bean-shaped organs located throughout the body that fight disease. A conjunctival melanoma tends to recur (come back after treatment) on the eye’s surface and looks like dark spots on the eye. Doctors often perform a biopsy on a spot that appears to be conjunctival melanoma. A biopsy is the removal of a sample of the tissue for examination under a microscope.
- Eyelid carcinoma (basal or squamous cell) is a variation of skin cancer. This tumor may be surgically removed and is usually not dangerous if it is treated early.
- Lacrimal gland tumor is a benign or malignant tumor of the glands that produce tears.
Facts About Retinoblastoma
This information was developed by the National Eye Institute to help patients and their families search for general information about retinoblastoma. An eye care professional who has examined the patient’s eyes and is familiar with his or her medical history is the best person to answer specific questions.
Retinoblastoma Defined
What is retinoblastoma?
Retinoblastoma is a type of cancer that forms in the retina (the light-sensitive tissue at the back of the eye).
Risk Factors
Who is at risk for retinoblastoma?
The disease usually occurs in children younger than 5 years and may be in one eye or in both eyes. In some cases the disease is inherited from a parent.
Treatment
How is retinoblastoma treated?
Retinoblastoma is a serious, life-threatening disease. However, with early diagnosis and timely treatment, in most cases, a child’s eyesight and life can be saved.
Last Reviewed: October 2010
The National Eye Institute (NEI) is part of the National Institutes of Health (NIH) and is the Federal government’s lead agency for vision research that leads to sight-saving treatments and plays a key role in reducing visual impairment and blindness.
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