RISK OF OCULAR MELANOMA IN RELATION TO CUTANEOUS AND IRIS NEVI

A case-control study was set up to assess the risk of eye melanoma in relation to the number and type of cutaneous melanocytic naevi and pig mented lesions of the iris. Cases comprised 211 unselected ocular mela noma patients attending the Ocular Oncology Clinic at Moorfields Eye H ospital, London, during November 1990 to October 1991 and diagnosed af ter August 1986. Hospital and general practice controls (416) were rec ruited in the North East Thames Region of the UK. Cutaneous naevi grea ter than or equal to 2 mm in diameter were counted on the skin. Clinic ally atypical and congenital naevi were recorded separately. Pigmented lesions of the iris were counted. The relative risk for ocular melano ma increased with numbers of atypical naevi and numbers of common naev i. Ten percent of cases but 3% of controls had at least 100 naevi of 2 mm or greater diameter. Seven percent of cases and 0.4% of controls h ad 4 or more atypical naevi. Pigmented lesions of the iris were signif icantly more common in cases than controls. Nine percent of cases had the Atypical Mole syndrome (AMS) phenotype compared with 1% of control s. Six cases had concurrent cutaneous melanoma primaries. We conclude that atypical and iris naevi are important risk factors for eye melano ma and that patients with eye melanoma are at creased risk of cutaneou s melanoma. Dermatological examination for the AMS phenotype and cutan eous melanoma should be recommended in eye melanoma patients with larg e numbers of pigmented lesions of the skin or family history of melano ma. (C) 1995 Wiley-Liss, Inc.