Eye color and cutaneous nevi predict risk of ocular melanoma in Australia

Ethnicity, cutaneous nevi and eye color are generally accepted risk factors for melanoma of the eye. although case-control studies have produced confl icting results. We sought to determine the constitutional risk factors for melanomas of the choroid, ciliary body, iris and conjunctiva in Australia. A population-based case-control study was conducted, with case ascertainmen t from a prospective national incidence survey and randomly selected commun ity controls. Two hundred and ninety cases aged 18-79 years and diagnosed b etween I st January 1996 and 31st July 1998 were enrolled with 916 controls frequency matched by age, sex and State or Territory of residence, Risk of choroidal and ciliary body melanoma (n = 246) was increased in people with grey (OR 2.9, 95% CI 1.5-5.5), hazel (OR 2.2, 95% CI 1.4-3.7) and blue eye s (OR 1.7, 95% CI 1.0-2.7) compared with brown eyes, Risk was also increase d in those with 4 or more nevi on their back, those unable to tan, and thos e who squinted when outdoors as a child. Risk was reduced in people born ot her than in Australia and New Zealand (OR 0.7, 95% CI 0.5-1.0), Non-brown e ye color was a risk factor for iris melanoma (n = 25), No risk factors were identified for conjunctival melanoma (n = 19), Eye color is the strongest constitutional predictor of choroidal and ciliary body melanoma, and may in dicate a protective effect of melanin density at these sites. An independen t association with cutaneous nevi suggests a role for other genetic factors . (C) 2001 Wiley-Liss. Inc.