Abstract

The global burden of cancer is a major source of morbidity and mortality. In 2012, there were 14 million new cases of cancer and 8 million cancer-related deaths globally (IARC, 2014). By the year 2030, the incidence of cancer cases is globally expected to increase to 22 million (Bray, 2015). In general, the highest cancer incidence rates occur in the high-income countries of North America and Western Europe, in addition to Japan, Korea, and Australia (IARC, 2018a). The percentage of cancer cases attributable to workplace exposures in these developed nations is expected to decline in the coming years due to occupational exposure restrictions that have been in place now for several decades (Boffetta, 1999; IARC, 2018b). Overall age-adjusted death rates have been falling dramatically in the United States for lung, bronchus, colon, prostate (men), and breast (women) cancers for the past 20 years (ACS, 2018). According to International Agency for Research on Cancer (IARC), based on population sizes, more than 60% of all cancer cases occur in Africa, Asia, and Central and South America. These regions also account for 70% of all cancer fatalities (IARC, 2014). In addition, the burden of disease is expected to increase greatly in these lower economic countries in the next two decades due to aging populations, industrial growth, and other environmental and social risk factors (Stewart, 2016; Torre, 2015).