Precancerous conditions of the eye are changes to cells in the eye that make them more likely to develop into cancer. These conditions are not yet cancer. But if they are not treated, there is a chance that these changes will become eye cancer.
Primary acquired melanosis (PAM) is the most common precancerous condition of the
eye. It is caused by an overgrowth of the cells that make
To diagnose PAM, your doctor will do an eye exam. You may also have a biopsy to check whether any of the extra melanocytes have changed to become abnormal. If any cells are abnormal, this is called PAM with atypia. PAM with atypia is more likely to develop into cancer.
PAM that affects 1/4 of the eye or less can be treated with active surveillance. You will have other treatment if anything changes.
If you’re diagnosed with PAM in a large area of the conjunctiva or PAM with atypia, treatment options include:
Conjunctival intraepithelial neoplasia (CIN) develops when
CIN is graded from 1 to 3 based on how much of the conjunctiva contains abnormal cells. It may also be described as mild, moderate or severe.
Grade 1 is also called mild CIN. Abnormal cells are found in 1/3 or less of the layers of the conjunctiva. It usually affects the part of the conjunctiva closest to the cornea.
Grade 2 is also called moderate CIN. Abnormal cells are found in about 2/3 of the layers of the conjunctiva.
Grade 3 is also called severe CIN. Almost all layers of the conjunctiva are affected, but abnormal cells have not yet made it to the layer of connective tissue.
CIN often appears as a white, greyish or yellowy piece of thick but see-through tissue on the surface of the conjunctiva. Your eye may also be red and irritated.
To diagnose CIN, your doctor will do an eye exam that may include ocular coherence
tomography (OCT) or fluorescent
Your healthcare team will consider things like the grade when deciding how to treat conjunctival intraepithelial neoplasia. Treatment options for CIN include:
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