Abstract
Abstract: :
Purpose: To study iris pigmentation histologically in a series of patients with enucleated eyes for choroidal and ciliary body melanoma to determine if lightly pigmented irides are associated with increased risk of death from these tumors. Methods: The subjects comprise a series of 469 enucleated eyes with patient follow–up data that examined histologically for degree of iris pigmentation. The amount of iris melanin pigmentation was graded 0 to 7. For statistical analysis, groups 0 to 2 were combined to include 51% of the cases approximating the frequency of blue–gray irides in patients with uveal melanoma, group 3 included 29% of the patients approximating the frequency of green–hazel irides and groups 4–7 were combined to approximate the frequency of brown irides. Cox regression analysis was used to test for association between predicted iris color and death from metastatic uveal melanoma. Tumor size and cell type were covariables in the analysis. Results: The association between predicted iris color and death was weak (hazard ratio 1.5 for blue versus brown eye, p = 0.12). We estimate that the chance of a type II error is grater than that of a type I error in our study. Conclusions: There is a weak association between risk of metastatic death from choroidal melanoma and degree of iris pigmentation.
Keywords: melanoma • iris • pathology: human