Geographic variation and secular trends of breast cancer incidence and mortality in the world

Abstract

Objective: Breast cancer (BC) is a common cancer among women worldwide, accounting for 16% of the total annual incidence of cancer among women. The present study aimed to investigate and compare the incidence and mortality of BC on the basis of different geographical, political and economic divisions in the world as well as investigating long-term trends of the incidence and mortality of this cancer worldwide. Materials and Methods: In the present study, we extracted the information on the incidence and mortality of BC in 184 countries from the International Agency for Research on Cancer (IARC) (Project GLOBOCAN, 2012). The present study categorized and presented the information on the Age-Standardized Incidence Rate (ASIR) and Age Standardized Mortality Rate (ASMR) of BC based on the continents, world regions based on the development level, World Health Organization (WHO) regions classification and Human Development Index (HDI). Results: The highest ASIR of BC was observed in regions with a very high HDI (ASIR=78.2), in PAHO (ASIR=67.6), North America (ASIR=91.6) and more developed regions (ASIR=73.4); and the highest ASMR in regions with a low HDI (ASMR=17), in EMRO (ASMR=18.6), more developed regions (ASMR=14.9) and Africa (ASMR=17.3). The ASIR of BC had an ascending trend and the ASMR of this cancer was decreasing from 1975 to 2010. There was a positive statistical correlation equal to 0.883 between ASMR and ASIR of BC in the world. Conclusions: There was a significant positive correlation between ASIR and ASMR of BC. The ASIR of BC was increasing in most regions of the world, while the mortality rate was decreasing in the world from 1975 to 2010.

Keywords

• epidemiology
• geographical distribution
• secular trends
• breast cancer