High UVR Exposure at Birth Location, Sun-Sensitive Skin Type, and History of Skin Cancer Decrease Pancreatic Cancer Risk
(ChemotherapyAdvisor) – Exposure to high ultraviolet radiation (UVR) at an individual's birth location confers a lower risk of pancreatic cancer, according to results of a study presented June 19 at the American Association for Cancer Research's Pancreatic Cancer: Progress and Challenges conference in Lake Tahoe, NV.
Sun-sensitive skin type and a history of skin cancer also each decreased risk for pancreatic cancer, said Rachel E. Neale, PhD, of the Queensland Institute of Medical Research, Brisbane, Queensland, Australia.
Noting conflicting studies of the effect of sun exposure and serum 25 hydroxy vitamin D on pancreatic cancer, Dr. Neale and colleagues conducted a population-based case-control study between 2007 and 2011, recruiting 704 cases and 709 age- and sex-matched controls.
Each participant was interviewed to capture sociodemographic, medical history, and lifestyle information; also determined was location of birth, skin cancer history, and skin type (measured as skin color, tanning ability, and propensity to burn). NASA's Total Ozone Mapping Spectrometer (TOMS) was used to assign an ambient UVR value to each location of birth, which was then divided into tertiles.
Mean age of all participants was 67 years; approximately 60% of both cases and controls were men. After adjusting for age, sex, smoking, diabetes, BMI, and alcohol use, those born in high UVR areas were at lower risk of pancreatic cancer than those born in low UVR areas (OR highest versus lowest UVR tertile 0.76 [95% CI: 0.56–1.01]).
“All measures of skin type were significantly associated with pancreatic cancer risk, with those with the most sun-sensitive skin being at approximately half the risk of those with the least sun-sensitive skin,” Dr. Neale reported. People diagnosed with skin cancer or other sun-related skin lesions had a 40% lower risk of pancreatic cancer than those who had not had skin lesions treated (OR 0.60 [95% CI: 0.48–0.75]).
Given findings of studies examining circulating vitamin D, it is possible that if exposure to UVR does decrease risk of pancreatic cancer, it is acting independently of vitamin D, she noted, concluding that “understanding the potentially complex role of ultraviolet radiation in pancreatic cancer needs further study, as this may provide an avenue for preventive strategies.”