Global trends in nasopharyngeal cancer mortality since 1970 and predictions for 2020: Focus on low-risk areas

Nasopharyngeal cancer (NPC) mortality shows great disparity between endemic high risk areas, where non-keratinizing carcinoma (NKC) histology is prevalent, and non-endemic low risk regions, where the keratinizing squamous cell carcinoma (KSCC) type is more frequent. We used the World Health Organization database to calculate NPC mortality trends from 1970 to 2014 in several countries worldwide. For the European Union (EU), the United States (US) and Japan, we also predicted trends to 2020. In 2012, the highest age-standardized (world standard) rates were in Hong Kong (4.51/100,000 men and 1.15/100,000 women), followed by selected Eastern European countries. The lowest rates were in Northern Europe and Latin America. EU rates were 0.27/100,000 men and 0.09/100,000 women, US rates were 0.20/100,000 men and 0.08/100,000 women and Japanese rates were 0.16/100,000 men and 0.04/100,000 women. NPC mortality trends were favourable for several countries. The decline was -15% in men and -5% in women between 2002 and 2012 in the EU, -12% in men and -9% in women in the US and about -30% in both sexes in Hong Kong and Japan. The favourable patterns in Europe and the United States are predicted to continue. Changes in salted fish and preserved food consumption account for the fall in NKC. Smoking and alcohol prevalence disparities between sexes and geographic areas may explain the different rates and trends observed for KSCC and partially for NKC. Dietary patterns, as well as improvement in management of the disease, may partly account for the observed trends, too.