tPurpose: To investigate the presence of known cytogenetic alterations of choroidalmelanoma in a series of patients diagnosed and treated in our Ocular Oncology Service.A review of the present literature on this topic is also presented.Methods: Microsatellite analysis (MSA) studies on loss of heterozygosity (LOH) of chromo-some 3, as well as multiplex ligation probe amplification (MLPA) on chromosomes 1, 3, 6and 8, were performed on enucleation or local resection samples obtained from a total of27 patients, over a 2-year period.Results: Twenty patients showed at least one of the cytogenetic alterations looked for. A totalof 11 cases were found that showed LOH of chromosome 3 (44%), 8 gains of chromosome 8(30%), 8 gains of chromosome 6 p (30%), and 7 partial or total losses of chromosome 1 (26%).Conclusions: This is the first study on the cytogenetics of choroidal melanoma performed inour country.The results are similar to that published in the literature.Cytogenetic analysis provides more accurate knowledge on a vital individual prognosis.It also may become a valuable tool for establishing the most adequate follow-up regimes,and the need for adjuvant therapies.