Biomedical subjects

Robyn M Brown

Publications and source records attributed to Robyn M Brown.

3 recordsLinked to original sources

PubMed2005

Melanocytic nevi in very young children: the role of phenotype, sun exposure, and sun protection.

BACKGROUND: Melanocytic nevi are strongly associated with cutaneous melanoma, yet little is known about factors influencing nevus development in the first years of life. OBJECTIVE: We sought to identify phenotypic and environmental factors associated with nevus counts in very young children. METHODS: In a cluster prevalence survey, full body nevus counts and phenotypic assessments were conducted on 193 children aged 1 to 3 years. Information on each child's sun exposure and sun protection practices was obtained through parental questionnaire. RESULTS: High total nevus counts were associated with heavy facial freckling, time spent outdoors on weekends in summer, and Caucasian ethnicity. Low nevus counts were associated with dark skin color, ability to tan, and frequent application of sunscreen. Frequent wearing of hats was specifically associated with low nevus counts on the face, but not at other sites. CONCLUSIONS: Nevi are common at a very young age among children in Queensland, Australia, and are associated with sun exposure and freckling. Diligent sun protection practices appear to reduce nevus burden, even after accounting for the effects of phenotype and sun exposure factors. Primary prevention strategies aimed at reducing sun exposure in very early life may be effective in reducing nevus prevalence and melanoma risk.

Australia↗

PubMed2003

Prevalence and anatomical distribution of naevi in young Queensland children.

Sunlight is the principal environmental cause of melanoma and has also been implicated in the pathogenesis of melanocytic naevi. Epidemiological evidence indicates that childhood is a period during which melanocytes are susceptible to the effects of sunlight, yet little is known about the development of naevi in infancy. We conducted a survey of child-care centres to document the prevalence and anatomical distribution of melanocytic naevi among 193 young children aged 1-3 years in Brisbane, Australia (latitude 27 degrees S). Naevi were counted on all skin surfaces except for the scalp, buttocks and genitalia. Overall, almost 90% of children in the study sample had at least 1 naevus of any size, and more than 30% of children had 10 or more naevi. Total naevus counts ranged from 0 to 45 and were strongly determined by age. When taken together, naevus densities were highest on exposed body sites such as the face and limbs; however the density of large naevi (> or = 5 mm) was significantly higher on the trunk than on the face, neck and ears. These data support the concept that melanocytic neoplasia commences early in life and that naevus evolution is influenced by the anatomical site of the target cell.

Child, Preschool↗

PubMed2003

A rapid method for determining recent sunscreen use in field studies.

The role of sunscreens in preventing skin cancer and melanoma is the focus of ongoing research. Currently, there is no objective measure which can be used in field studies to determine whether a person has applied sunscreen to their skin, and researchers must use indirect assessments such as questionnaires. We sought to develop a rapid, non-invasive method for identifying sunscreen on the skin for use in epidemiological studies. Our basic method is to swab the skin, elute any residues which have been adsorbed onto the swab by rinsing in ethanol, and submit the eluted washings for spectrophotometric analysis. In a controlled study, we applied 0.1 ml of sunscreen to a 50 cm(2) grid on both forearms of 21 volunteers. Each forearm was allocated one of 10 different sunscreen brands. The skin was swabbed after intervals of 20 min, 1 h, 2 h and 4 h. In a field study conducted among 12 children aged 2-4 years attending a child care centre, sunscreen was applied to the faces of half the children. Swabs were then taken from the face and back of all children without knowledge of sunscreen status. In the controlled study, sunscreen was clearly detectable up to 2 h after application for all brands containing organic sunscreen, and marginally detectable at 4 h. In the field study, this method correctly identified all children with and without sunscreen. We conclude that spectrophotometric analysis of skin swabs can reliably detect the presence of sunscreen on the skin for up to 2 h after application.

Adult↗