PLoS ONE (Jan 2013)

Sunny holidays before and after melanoma diagnosis are respectively associated with lower Breslow thickness and lower relapse rates in Italy.

  • Sara Gandini,
  • Esther De Vries,
  • Giulio Tosti,
  • Edoardo Botteri,
  • Giuseppe Spadola,
  • Patrick Maisonneuve,
  • Chiara Martinoli,
  • Arjen Joosse,
  • Pier Francesco Ferrucci,
  • Federica Baldini,
  • Emilia Cocorocchio,
  • Elisabetta Pennacchioli,
  • Francesco Cataldo,
  • Barbara Bazolli,
  • Alessandra Clerici,
  • Massimo Barberis,
  • Veronique Bataille,
  • Alessandro Testori

DOI
https://doi.org/10.1371/journal.pone.0078820
Journal volume & issue
Vol. 8, no. 11
p. e78820

Abstract

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BACKGROUND: Previous studies have reported an association between sun exposure and improved cutaneous melanoma (CM) survival. We analysed the association of UV exposure with prognostic factors and outcome in a large melanoma cohort. METHODS: A questionnaire was given to 289 (42%) CM patients at diagnosis (Group 1) and to 402 CM patients (58%) during follow-up (Group 2). Analyses were carried out to investigate the associations between sun exposure and melanoma prognostic factors and survival. RESULTS: Holidays in the sun two years before CM diagnosis were significantly associated with lower Breslow thickness (p=0.003), after multiple adjustment. Number of weeks of sunny holidays was also significantly and inversely associated with thickness in a dose-dependent manner (p=0.007). However when stratifying by gender this association was found only among women (p=0.0004) the risk of CM recurrence in both sexes was significantly lower in patients (n=271) who had holidays in the sun after diagnosis, after multiple adjustment including education: HR=0.30 (95%CI:0.10-0.87; p=0.03) conclusions: Holidays in the sun were associated with thinner melanomas in women and reduced rates of relapse in both sexes. However, these results do not prove a direct causal effect of sun exposure on survival since other confounding factors, such as vitamin D serum levels and socio-economic status, may play a role. Other factors in sun seeking individuals may also possibly affect these results.