A malignant neoplasm that arises from the pigmented cells of the uveal tract of the eye. The peak incidence of this tumor is in the 6th decade of life and they are most frequent in caucasians. Clinically the lesions may present with visual loss or be identified during routine ocular examination. They may be locally invasive or metastasize to distant sites. Histologically, ocular melanomas are characterized by spindle cells featuring elongated nuclei and minimal cytoplasm or epithelioid cells which are pleomorphic, have enlarged nuclei and prominent cytoplasm. The later may be referred to as "non-spindle cell" melanomas. (From: Cancer Control; JMCC 5(4):299-309, 1998)