Ocular Melanoma
Ocular melanoma (OM) is a cancer in pigment-producing cells of the http://www.cancer.gov/Common/PopUps/popImage.aspx?imageName=/images/cdr/live/CDR543553-750.jpg&caption=Anatomy%20of%20the%20eye,%20showing%20the%20outside%20and%20inside%20of%20the%20eye%20including%20the%20sclera,%20cornea,%20iris,%20ciliary%20body,%20choroid,%20retina,%20vitreous%20humor,%20and%20optic%20nerve.%20The%20vitreous%20humor%20is%20a%20liquid%20that%20fills%20the%20center%20of%20the%20eye." target="_blank">eye called melanocytes. Melanocytes are cells that produce the pigment melanin that colors the skin, hair, and eyes, as well as forms moles. There are four tissues in the eye in which melanoma can develop: http://www.nlm.nih.gov/medlineplus/ency/article/002337.htm" target="_blank">the uveal tract (uvea); http://library.thinkquest.org/C005949/anatomy/conjunctiva.htm" target="_blank">conjunctiva; eyelid; and http://www.emedicinehealth.com/script/main/art.asp?articlekey=4658" target="_blank">orbit. The uvea - the middle layer within the eye - is divided into three main parts: the http://www.cancer.gov/common/popUps/popDefinition.aspx?id=CDR0000534221&version=Patient&language=English" target="_blank">iris, http://www.cancer.gov/common/popUps/popDefinition.aspx?id=CDR0000534222&version=Patient&language=English" target="_blank">ciliary body, and http://www.cancer.gov/common/popUps/popDefinition.aspx?id=CDR0000534223&version=Patient&language=English" target="_blank">choroid. Uveal melanoma, also called http://rarediseases.info.nih.gov/GARD/Condition/8621/Intraocular_melanoma.aspx" target="_blank">intraocular melanoma, is the most common ocular melanoma. Conjunctival melanoma manifests on the surface of the eye and has been increasing in incidence. Eyelid and primary orbital melanoma are the least common variants.