Sunny holidays before and after melanoma diagnosis are respectively associated with lower Breslow thickness and lower relapse rates in Italy.
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.
Division of Epidemiology and Biostatistics, European Institute of Oncology, Milan, Italy.
Sara
S
Gandini
Esther
E
De Vries
Giulio
G
Tosti
Edoardo
E
Botteri
Giuseppe
G
Spadola
Patrick
P
Maisonneuve
Chiara
C
Martinoli
Arjen
A
Joosse
Pier Francesco
PF
Ferrucci
Federica
F
Baldini
Emilia
E
Cocorocchio
Elisabetta
E
Pennacchioli
Francesco
F
Cataldo
Barbara
B
Bazolli
Alessandra
A
Clerici
Massimo
M
Barberis
Veronique
V
Bataille
Alessandro
A
Testori
D000328:Adult; D015331:Cohort Studies; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005500:Follow-Up Studies; D006693:Holidays; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008297:Male; D008545:Melanoma / Q000175:diagnosis* / Q000453:epidemiology; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local; D011379:Prognosis; D018570:Risk Assessment / Q000379:methods / Q000706:statistics & numerical data; D012307:Risk Factors; D012867:Skin / Q000473:pathology / Q000528:radiation effects; D012878:Skin Neoplasms / Q000175:diagnosis* / Q000453:epidemiology; D013472:Sunlight; D011795:Surveys and Questionnaires; D013997:Time Factors; D014466:Ultraviolet Rays