Sun exposure and mortality from melanoma.
BACKGROUND
Melanoma incidence and survival are positively associated, both geographically and temporally. Solar elastosis, a histologic indicator of cutaneous sun damage, has also been positively associated with melanoma survival. Although these observations raise the possibility that sun exposure increases melanoma survival, they could be explained by an association between incidence and early detection of melanoma. We therefore evaluated the association between measures of skin screening and death from cutaneous melanoma.


METHODS
Case subjects (n = 528) from a population-based study of cutaneous melanoma were followed for an average of more than 5 years. Data, including measures of intermittent sun exposure, perceived awareness of the skin, skin self-screening, and physician screening, were collected during in-person interviews and review of histopathology and histologic parameters (i.e., solar elastosis, Breslow thickness, and mitoses) for all of the lesions. Competing risk models were used to compute risk of death (hazard ratios [HRs], with 95% confidence intervals [CIs]) from melanoma. All statistical tests were two-sided.


RESULTS
Sunburn, high intermittent sun exposure, skin awareness histories, and solar elastosis were statistically significantly inversely associated with death from melanoma. Melanoma thickness, mitoses, ulceration, and anatomic location on the head and neck were statistically significantly positively associated with melanoma death. In a multivariable competing risk analysis, skin awareness (with versus without, HR = 0.5, 95% CI = 0.3 to 0.9, P = .022) and solar elastosis (present versus absent, HR = 0.4, 95% CI = 0.2 to 0.8, P = .009) were strongly and independently associated with melanoma death after adjusting for Breslow thickness, mitotic index, and head and neck location, which were also independently associated with death.


CONCLUSIONS
Sun exposure is associated with increased survival from melanoma.
Berwick
Marianne
M
University of New Mexico, Department of Internal Medicine, New Mexico Cancer Research Facility, MSC08 4630, Room 103A, 1 University of New Mexico, Albuquerque, NM 87131, USA. mberwick@salud.unm.edu
Armstrong
Bruce K
BK
Ben-Porat
Leah
L
Fine
Judith
J
Kricker
Anne
A
Eberle
Carey
C
Barnhill
Raymond
R
D000328:Adult; D000368:Aged; D002117:Calcitriol / Q000378:metabolism; D016022:Case-Control Studies; D015986:Confounding Factors, Epidemiologic; D003237:Connecticut / Q000453:epidemiology; D004260:DNA Repair; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008545:Melanoma / Q000209:etiology / Q000401:mortality*; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D012107:Research Design; D018570:Risk Assessment; D012307:Risk Factors; D012878:Skin Neoplasms / Q000209:etiology / Q000401:mortality*; D013472:Sunlight / Q000009:adverse effects*; D011795:Surveys and Questionnaires; D015996:Survival Rate
D002117:Calcitriol