Is prostate cancer incidence worldwide linked to artificial light at night exposures? Review of earlier findings and analysis of current trends.

Widespread use of artificial light at night (ALAN) might contribute to the global burden of hormone-dependent cancers. Previous attempts to verify this association in population-level studies have been sparse. Using GLOBOCAN, US-DMSP, and World Bank 2010-2012 databases, we studied the association between ALAN and prostate cancer (PC) incidence in 180 countries worldwide, controlling for several country-level confounders. The PC-ALAN association emerged marginally significant when year-2012 PC age-standardized rate data were compared with ALAN levels (t = 1.886, p < .1); this association was more significant (t > 2.7; p < .01) when only 110 countries with well-maintained cancer registries were analyzed. Along with other variables, ALAN explains up to 79% of PC ASR variability. PC-ALAN association appears to vary regionally, with the greatest deviations in Central Africa, Small Island Developing States, Southeast Asia, and Gulf States.