A follow-up study of 113 patients with suspicious iris nevi who were referred to our clinic between 1973 and 1991 was carried out by: reviewing their clinical records, fluorescein angiography, obtaining recent data with cooperation of their own or the referring ophthalmologist and contacting patients for reexamination. After examination the diagnoses were: 64 suspicious nevi, 23 melanomas, 15 ciliary body tumors with iris involvement and 11 other pseudomelanomas. In the group of suspicious nevi 86% was localized in the inferior part and 66% in the temporal part of the iris; for the melanoma group these figures were 78% and 75% respectively. The chamber angle was more often involved in the melanoma group, 40% against 17% in the suspicious nevi group. In this group 11 cases (21.6%) showed growth during the follow-up (mean 10.6 years). In three cases the tumor was surgically removed, with as histopathologic diagnosis: 1 xanthogranuloma, 1 neurolemmoma and 1 possible melanoma. In the melanoma group 16 lesions (76%) showed growth during the follow-up (mean 7.2 years), in most cases within 5 years of the initial diagnosis. The lesion was surgically removed in 11 cases. The histopathologic diagnoses were: 8 melanomas, 1 xanthogranuloma, 1 possible melanoma and 1 metastasis of a skin melanoma. Our study shows that periodic ophthalmic check-ups are of great importance in the management of iris lesions suspect for melanoma.