The purposes of the proposed research are to study the natural course of untreated uveal melanoma and to evaluate the prognosis of enucleation using a no-touch procedure or a traumatic procedure. The specific objectives are to answer the following questions: (1) How often and at what stage in the natural course of untreated choroidal melanoma is metastatic disease encountered? (2) How often and how rapidly do small choroidal melanomas progress to tumors large enough to cause retinal detachment, opacification of the media, secondary glaucoma, and the like? (3) How often will metastatic disease be encountered following enucleation at different stages of choroidal melanoma (a) with a no-touch procedure or (b) with a traumatic procedure? These studies will be carried out on the animal model of rabbits in which Greene hamster melanoma has developed in the choroid, a model that is relevant to human melanoma. Greene hamster melanoma tissue will be implanted intrachoroidally in one eye. The rabbits that develop tumor will be divided into three groups. One group will be observed for the natural untreated course of the disease. The second group will be enucleated by a traumatic procedure at various stages of tumor growth by the no-touch procedure. The third group will be enucleated by a traumatic procedure at various stages of tumor growth. Complete autopsies will be performed to detect metastases. Enucleated eyes will be studied histologically.