The Queensland Study of Melanoma: environmental and genetic associations (Q-MEGA); study design, baseline characteristics, and repeatability of phenotype and sun exposure measures

Abstract

Cutaneous malignant melanoma (CMM) is a major health issue in Queensland, Australia, which has the world's highest incidence. Recent molecular and epidemiologic studies suggest that CMM arises through multiple etiological pathways involving gene-environment interactions. Understanding the potential mechanisms leading to CMM requires larger studies than those previously conducted. This article describes the design and baseline characteristics of Q-MEGA, the Queensland Study of Melanoma: Environmental and Genetic Associations, which followed up 4 population-based samples of CMM patients in Queensland, including children, adolescents, men aged over 50, and a large sample of adult cases and their families, including twins. Q-MEGA aims to investigate the roles of genetic and environmental factors, and their interaction, in the etiology of melanoma. Three thousand, four hundred and seventy-one participants took part in the follow-up study and were administered a computer-assisted telephone interview in 2002-2005. Updated data on environmental and phenotypic risk factors, and 2777 blood samples were collected from interviewed participants as well as a subset of relatives. This study provides a large and well-described population-based sample of CMM cases with follow-up data. Characteristics of the cases and repeatability of sun exposure and phenotype measures between the baseline and the follow-up surveys, from 6 to 17 years later, are also described.

FIGURE 1

Historic ascertainment of index cases for the four original samples, Queensland study of Melanoma: Environmental and Genetics Associations (Q-MEGA), Queensland, Australia, 1987–2005^{* *}Adolescent: The Study of Melanoma in Adolescents; Childhood: The Queensland Study of Childhood Melanoma; Men over 50: The Study of Men Over 50; QFMP: Queensland Familial Melanoma Project

FIGURE 2

Flow diagram showing steps in data collection from original ascertainment of index cases to most recent follow-up of the four original samples, Queensland study of Melanoma: Environmental and Genetics Associations (Q-MEGA), Queensland, Australia, 1987–2005 ^*Subjects for whom sufficient DNA was still available were not re-approached for blood. ^†See Methods for eligibility criteria.