Iris color as a prognostic factor in ocular melanoma

Background: Ocular melanoma may be more prevalent among patients with light irises than those with dark irises. Objective: To examine a large clinical series of patients with intraocular melanoma to determine if light irises are associated with increased risk of death from these tumors. Methods: A total of 1162 patients treated with proton irradiation between 1 984 and 1996 were observed through 1997. Results: Iris color in the patients was blue or gray in 48%, green or hazel . in 30%, and brown in 23%. Tumors in patients with blue or gray irises wer e less headily pigmented (P < .001) and closer to the optic disc and macula (P < .001). Five- and 10-year metastasis-related death rates were 0.14 and 0.21, respectively, for those with blue or gray irises and 0.10 and 0.15, respectively, for those with darker irises (P = .02). In a Cox proportional hazards regression controlling for tumor characteristics, patients with bl ue or gray irises died of metastatic disease at a rate 1.90 times (95% conf idence interval, 1.26-2.85) that of patients with brown irises. The rate of metastatic death was not significantly elevated for those with green or ha zel irises (relative risk, 1.43; 95% confidence interval, 0.91-2.23). Conclusion: Patients with blue or gray irises appear to be at increased ris k of metastatic death from choroidal melanoma, independent of other risk fa ctors.