A M Laino1, E G Berry1,2, K Jagirdar1, K J Lee1, D L Duffy1,3, H P Soyer1,4, R A Sturm1. 1. Dermatology Research Centre, The University of Queensland, UQ Diamantina Institute, Translational Research Institute, Brisbane, 4102, Australia. 2. Department of Dermatology, Emory University School of Medicine, Atlanta, 30309, GA, U.S.A. 3. QIMR Berghofer Medical Research Institute, Brisbane, 4006, Australia. 4. Department of Dermatology, Princess Alexandra Hospital, Brisbane, 4102, Australia.
Abstract
BACKGROUND: Iris naevi and iris freckles have a frequency of 4% and 50% in the European population, respectively. They are associated with dysplastic naevi, but few studies have examined their link to cutaneous melanoma. OBJECTIVES: To assess whether iris pigmented lesions are a predictive indicator for cutaneous melanoma. METHODS: This is a melanoma case-control study of 1254 European-background Australians. Sun exposure and melanoma history, a saliva sample for DNA analysis and eye photographs taken with a digital camera were collected from 1117 participants. Iris images were assessed by up to four trained observers for the number of iris pigmented lesions. The data were analysed for correlations between iris pigmented lesions and melanoma history. RESULTS: Case participants over the age of 40 had similar numbers of iris pigmented lesions to age matched controls (mean 5·7 vs. 5·2, P = 0·02), but in younger case and control participants there was a greater difference (mean 3·96 vs. 2·19, P = 0·004). A logistic regression adjusted for age, sex, skin, hair and eye colour, skin freckling and naevus count found that the presence of three or more iris pigmented lesions increases the melanoma risk 1·45-fold [95% confidence interval (CI) 1·07-1·95]. HERC2/OCA2 rs12913832 and IRF4 rs12203592 influenced both eye colour and the number of iris pigmented lesions. On the HERC2/OCA2 A/A and A/G genotype background there was an increasing proportion of blue eye colour when carrying the IRF4 T allele (P = 3 × 10-4 ) and a higher number of iris pigmented lesions with the IRF4 T/T homozygote (P = 3 × 10-9 ). CONCLUSIONS: Iris pigmented lesion count provides additional predictive information for melanoma risk above that from conventional risk factors.
BACKGROUND: Iris naevi and iris freckles have a frequency of 4% and 50% in the European population, respectively. They are associated with dysplastic naevi, but few studies have examined their link to cutaneous melanoma. OBJECTIVES: To assess whether iris pigmented lesions are a predictive indicator for cutaneous melanoma. METHODS: This is a melanoma case-control study of 1254 European-background Australians. Sun exposure and melanoma history, a saliva sample for DNA analysis and eye photographs taken with a digital camera were collected from 1117 participants. Iris images were assessed by up to four trained observers for the number of iris pigmented lesions. The data were analysed for correlations between iris pigmented lesions and melanoma history. RESULTS: Case participants over the age of 40 had similar numbers of iris pigmented lesions to age matched controls (mean 5·7 vs. 5·2, P = 0·02), but in younger case and control participants there was a greater difference (mean 3·96 vs. 2·19, P = 0·004). A logistic regression adjusted for age, sex, skin, hair and eye colour, skin freckling and naevus count found that the presence of three or more iris pigmented lesions increases the melanoma risk 1·45-fold [95% confidence interval (CI) 1·07-1·95]. HERC2/OCA2rs12913832 and IRF4rs12203592 influenced both eye colour and the number of iris pigmented lesions. On the HERC2/OCA2 A/A and A/G genotype background there was an increasing proportion of blue eye colour when carrying the IRF4 T allele (P = 3 × 10-4 ) and a higher number of iris pigmented lesions with the IRF4 T/T homozygote (P = 3 × 10-9 ). CONCLUSIONS:Iris pigmented lesion count provides additional predictive information for melanoma risk above that from conventional risk factors.
Authors: Frida Lona-Durazo; Rohit Thakur; Erola Pairo-Castineira; Karen Funderburk; Tongwu Zhang; Michael A Kovacs; Jiyeon Choi; Ian J Jackson; Kevin M Brown; Esteban J Parra Journal: iScience Date: 2022-05-30
Authors: Uyen Koh; Monika Janda; Joanne F Aitken; David L Duffy; Scott Menzies; Richard A Sturm; Helmut Schaider; Brigid Betz-Stablein; Tarl Prow; H Peter Soyer; Adele C Green Journal: BMJ Open Date: 2018-09-19 Impact factor: 2.692