Malignant Melanoma
Cutaneous malignant melanoma is an invasive tumor of malignant melanocytes. On the eyelid, it accounts for about 1% of all eyelid malignancies. Ultraviolate light is a major factor in the pathogensis of cutaneous melanoma. On the eyelids, melanomas usually appear as asymmetric lesions with irregular borders, uneven distribution of color, diameters over 6 mm, and a history of growth. In the orbit, most melanomas arise as secondary tumors spreading from intraocular choroidal primary sites or from the conjunctiva or eyelids. Orbital lesions present with proptosis, ptosis, chemosis, orbital pain, and ophthalmoplegia. The treatment of choice for eyelid and localized orbital tumors is complete surgical excision with wide tumor-free margins. More extensive orbital tumors may require orbital exenteration.