title: Ambient temperature and risk of first primary basal cell carcinoma: A nationwide United States cohort study.
abstract: The Earth's surface is warming and animal studies have shown higher temperatures promote ultraviolet radiation (UVR) skin carcinogenesis. There are, however, no population studies of long-term temperature exposure and basal cell carcinoma (BCC) risk. We linked average lifetime summer ambient temperatures (based on weather station data) and satellite-based UVR estimates to self-reported lifetime residences in the U.S. Radiologic Technologists' cohort. We assessed the relationship between time-dependent average lifetime summer ambient temperature (20-year lag) in quintiles and BCC in whites, using Cox proportional hazards regression. Risks were adjusted for time-dependent lagged average lifetime UVR and time outdoors, body mass index, eye color, and sex (baseline hazard stratified on birth cohort). During a median 19.4 years follow-up, we identified 3556 BCC cases. There was no significant trend in risk between temperature and BCC. However, BCC risk was highest in the fourth quintile of temperature (Q4 vs. Q1; hazards ratio (HR)=1.18; 95% confidence interval (CI)=1.06-1.31, p-trend=0.09). BCC risk was strongly related to average lifetime ambient UVR exposure (Q5 vs. Q1; HR=1.54 (95% CI=1.35-1.75, p-trend=<0.001)). Future studies of temperature and BCC risk should include a broad range of UVR and temperature values, along with improved indicators of exposure to temperatures and UVR.
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA. Electronic address: freedmam@mail.nih.gov.
authors.forename: D
authors.initials: D
authors.lastname: Michal Freedman
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA.
authors.forename: Cari M
authors.initials: CM
authors.lastname: Kitahara
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA.
authors.forename: Martha S
authors.initials: MS
authors.lastname: Linet
authors.affiliation: Division of Environmental Health Sciences, School of Public Health, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Bruce H
authors.initials: BH
authors.lastname: Alexander
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA.
authors.forename: Gila
authors.initials: G
authors.lastname: Neta
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA.
authors.forename: Mark P
authors.initials: MP
authors.lastname: Little
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA.
authors.forename: Elizabeth K
authors.initials: EK
authors.lastname: Cahoon
mesh_terms: D000328:Adult; D015992:Body Mass Index; D002280:Basal Cell Carcinoma / Q000209:etiology*; D015331:Cohort Studies; D005127:Eye Color; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D016016:Proportional Hazards Models; D012307:Risk Factors; D012737:Sex Factors; D012878:Skin Neoplasms / Q000209:etiology*; D013696:Temperature; D014466:Ultraviolet Rays