Impact of iris color on uveal melanoma-related outcomes in 7245 patients at a single ocular oncology center

PURPOSE:To determine the relationship between iris color and uveal melanoma (UM)-related metastasis and death in a large cohort of patients from a single ocular oncology center. DESIGN:Retrospective case series. SUBJECTS:Patients diagnosed with UM between February 1971 and August 2007. METHODS:Patient information was obtained from chart documentation. MAIN OUTCOME MEASURES:UM-related metastasis and death. RESULTS:Out of 7245 patients, iris color was blue in 3702 (51%), green in 1458 (20%), and brown in 2085 (29%). Mean age was 58 ± 15 years and mean tumor thickness was 5.5 ± 3.3 millimeters. Some clinical features differed between iris color groups, with the blue irides group having a larger proportion of post-equatorial tumors with significantly closer proximity to the foveola and optic disc compared to the brown irides group. At a mean follow-up of 75 months, there was no statistically significant difference in metastasis between the various iris color groups. On univariate analysis, those with blue irides showed a higher incidence of UM-related death compared to the green and brown irides groups (8.3%, 5.9% and 7.5% respectively, p value = 0.02). Kaplan-Meier event free survival from UM-related death significantly differed only between the blue and green irides groups (p value = 0.007) with the green irides group showing the highest survival. However, on multivariate analysis, iris color was not predictive of UM-related death. CONCLUSION:Iris color was not predictive of UM-related metastasis or death. However, Kaplan-Meier survival at 20 years was poorest for blue irides group compared to green.