Background: Patients with melanoma- associated retinopathy (MAR)experience different visual symptoms caused by the production of antitumoral antibodies that cross- react with retinal epitopes. Immunofluorescence assays of serum from patients with MAR on sectioned monkey or human retina characteristically reveal antibody activity located within the inner nuclear layer, with a focus of activity upon the membranes of bipolar cells. Objectives: We inquired into the association with disease of this serological abnormality by evaluating sera from patients with melanoma with no MAR- like signs or symptoms. Methods: Groups of patients were selected with different stages of melanoma (American Joint Committee on Cancer stages I- IV). Seventy- seven serum samples from 51 patients with melanoma were examined by indirect immunohistochemical assay on sections of human retina. Results: Of the 77 serum samples, 53 were found to contain antibodies reactive with various components of retina. Eight were from 17 sera from patients in stage I or II, 14 were from 23 sera from patients in stage III, and 31 were from 37 sera from patients in stage IV. Statistical analysis revealed a correlation between antibody activity and the stage of disease, with a higher percentage of antibody activity in advanced stages (P=0.0002). Conclusions: The presence of antiretinal antibodies in patients with melanoma without ocular symptoms appears to be more common than previously suspected. Antibody activity similar to that ascribed to the MAR syndrome appears in some patients with melanoma who have no MAR- like retinopathy. Follow- up studies will determine if patients with antiretinal antibodies go on to develop MAR and if staining intensity and staining patterns change over the course of the disease. Background: Patients with melanoma-associated retinopathy (MAR) experience different visual symptoms caused by the production of antitumoral antibodies that cross- react with retinal epitopes. Immunofluorescence assays of serum from patients with MAR on sectioned monkey or human retina characteristically reveal antibody activity located within the inner nuclear layer, with a focus of activity on the membranes of bipolar cells. Objectives: We inquired into the association with disease of this serological abnormality by evaluating sera from patients with melanoma with no MAR-like signs or symptoms. Methods: Groups of patients were selected with different stages of melanoma (American Joint Committee on Cancer stages I-IV). Seventy-seven serum samples from 51 patients with melanoma were examined by indirect immunohistochemical assay on sections of human retina. Results: Of the 77 serum samples, 53 were found to contain antibodies reactive with various components of retina. Eight were from 17 sera from patients in stage I or II, 14 were from 23 sera from patients in stage III, and 31 were from 37 sera from patients in stage IV. Statistical analysis revealed a correlation between antibody activity and the stage of disease, with a Conclusions: The presence of antiretinal antibodies in patients with melanoma without ocular symptoms appears to be more common than previously suspected. Antibody activity similar to that ascribed to the MAR syndrome appears in some patients with melanoma who have no MAR- like retinopathy. Follow-up studies will determine if patients with antiretinal antibodies go on to develop MAR and if staining intensity and staining patterns change over the course of the disease.