Malignant melanoma, which develops in the pigment-producing melanocytes, is the most aggressive type of skin cancer. The most important risk factor for developing this cancer is exposure to the ultra-violet light of the sun. Genetic factors are also involved, with first-degree relatives of melanoma patients recognised to be at significantly greater risk than those with no family history of the disease. Many studies have suggested that, despite this greater risk, relatives of melanoma patients are no more likely to shun sunbathing or use sun protection than those with no increased risk. However, there have so far been no reports of attitudes to both sun protection and sunbathing in the same study.

Sharon Manne of the University of Medicine and Dentistry of New Jersey, New Brunswick, New Jersey, USA and co-workers in Philadelphia, PA and Tampa, FL, have evaluated a range of self-reported sunbathing and sun protection behaviours in a cohort of first degree relatives of melanoma patients, and correlated these to demographic and psychological factors, social influences and levels of knowledge about melanoma and its causes. A total of 545 English-speaking, adult first-degree relatives of patients diagnosed with cutaneous malignant melanoma without evidence of a familial melanoma syndrome were recruited into the study. Each also had at least one additional risk factor for melanoma, such as blonde or red hair, marked freckling, or significant sun exposure or burning during youth; none reported taking any particular skin protection or skin surveillance precautions; and none had a previous history of any skin cancer or abnormal moles. A total melanoma risk factor was calculated for each participant on a scale from 1 to 5, and the disease history of each participant's relative was extracted from medical records.

Each participant undertook an extensive telephone interview to determine their knowledge and perception of melanoma and its risk factors, their attitudes to sunbathing and sun protection, and related psychological factors and social influences. All items were scored on numerical scales and the results analysed by multiple regression to determine factors that correlate with both sunbathing behaviour and the use of sun protection.

A full set of data was obtained for almost all participants. Over all participants, the average use of sun protection was close to the centre of a 5-point scale, whereas the average level of sunbathing was below the average ("rarely"). These levels are lower than those reported in previous studies, which is particularly interesting as individuals who were highly aware of the risks of melanoma and the need to avoid sun exposure were excluded from the study. There was a moderate inverse correlation between the use of sun protection and sunbathing frequency.

Participants with higher general education levels and those with greater knowledge about risks of sun exposure were significantly more likely to engage in the use of sun protection. High levels of sun protection were also found in participants who were the offspring, rather than the parents or siblings, of melanoma patients. Not surprisingly, individuals who reported fewer psychological benefits of sunbathing and those who were more concerned about photo-aging were more likely to use sunscreen. Women and younger participants reported significantly higher levels of sunbathing. No medical factors apart, interestingly, from visits to the dentist correlated with sunbathing levels. But, also not surprisingly, participants who sunbathed were those who perceived benefits from doing so and saw it as "normative" behaviour in their social group.

Manne and her co-workers recognise that this study has some limitations and opens questions for further analysis. Given that, surprisingly, no correlation was noticed between either type of behaviour and the participants' attitudes to their relatives' cancer it will be interesting to explore the effect of communication between family members and relatives' attitude to risk. Nevertheless, the results suggest that interventions to improve sun protection might be best targeted to younger, less educated and female relatives of melanoma patients who are most sensitive to peer group norms.

Article:

Manne, S.L., Coups, E.J., Jacobsen, P.B., Ming, M., Heckman, C.J. and Lessin, S. (2011). Sun Protection and Sunbathing Practices among At-Risk Family Members of Patients with Melanoma. BMC Public Health, 11(1): 122. Published online ahead of print February 21, 2011. DOI:10.1186/1471-2458-11-122