Conjunctival tumors are malignant cancers that grow on the outer surface of the eye. The most common types of conjunctival tumors are squamous cell carcinoma, malignant melanoma, and lymphoma. Squamous cell carcinomas rarely metastasize, but can invade the area around the eye into the orbit and sinuses. Malignant melanomas can start as a nevus (freckle) or can arise as newly formed pigmentation. Lymphoma of the eye can be a sign of systemic lymphoma or be confined to the conjunctiva.
Both squamous cell carcinomas and malignant conjunctival melanomas should be removed. Most small conjunctival tumors can be photographed and followed for evidence of growth prior to treatment. Small tumors can be completely removed surgically. In other instances, cryotherapy (freezing therapy) may be necessary or chemotherapy eye drops may be used to treat the entire surface of the eye.