Global, Regional, and National Burden of Breast Cancer and Its Attributable Risk Factors Among Women, 1990–2017
Authors: Safiri Saeid , Naghavi Mohsen 
Published: October 2020

Abstract
Introduction: Breast cancer is the most common cancer in women worldwide. However, no comprehensive study has been conducted to compare the incidence, mortality, and disability-adjusted life years (DALYs) for female breast cancer among different countries. The current study examined the level and trends of incidence, death, and DALYs for breast cancer and its attributable risk factors among women in 195 countries from 1990 to 2017 by age, socio-demographic index (SDI; a composite of socio-demographic factors), and healthcare access and quality (HAQ; an indicator of health system performance) index.Methods: Vital registration, verbal autopsy, and cancer registries were used across the globe to generate estimates. Incidence, mortality, and DALYs were estimated. All estimates are presented as counts and age-standardised rates per 100,000 person-years. Results: Between 1990 and 2017 the global incidence of breast cancer increased significantly by 17.1% (95% uncertainty interval [UI]: 7.1–23.6; with 1.9 million incidences in 2017 [95% UI 1.9–2.0]; age-standardised rate of 45.9 [95% UI: 44.2–47.4]). However, over this same period the age-standardised death rate significantly decreased by 10.6% (95% UI: -19.5 to -4.4), with 600.7 thousand deaths in 2017 (95% UI: 578.7–630.0; age-standardised death rate of 14.1 95% UI: 13.6–14.8). Global DALYs also significantly decreased between 1990 and 2017 by 9.3% (95% UI: -19.9 to -1.6) with 17.4 million DALYs reported in 2017 (95% UI: 16.6–18.4; age-standardised rate of 414.7; 95% UI: 395.5– 437.6). Lebanon [138.3 (95% UI: 106.5–170.7)], the Netherlands [109.8 (95% UI: 97.4–122.7)], and the UK [102.6 (95% UI: 99.6–105.8)] had the three highest age-standardised incidence rates in 2017. Meanwhile, Pakistan [34.1 (95% UI: 20.9–71.3)], Tonga [34.0 (95% UI: 26.8–41.9)], and the Bahamas [33.3 (95% UI: 28.9–37.8)] had the three highest age-standardised death rates in 2017. Between 1990 and 2017, Saudi Arabia [232% (95% UI: 93–410)], Mauritius [174% (95% UI: 134–222)], and Taiwan [172% (95% UI: 141–208)] showed an increasing trend for the highest age-standardised incidence rate of breast cancer. Meanwhile, Mauritius [90% (95% UI: 66–117)], Philippines [76% (95% UI: 43–115)], and the Dominican Republic [69% (95% UI: 11–125)] produced the greatest significant increasing trend in age-standardised death rates. An increasing trend between population ageing and age-standardised incidence and death rates were observed globally, peaking among the oldest population grouping [incidence: 535.6 (95% UI: 511.8–560.7); death: 251.4 (95% UI: 242.6–260.9)]. Non-linear associations were observed between age-standardised DALY rates with SDI and HAQ. Alcohol consumption [9.2% (95% UI: 7.7–10.7)], high fasting plasma glucose [6.1% (95% UI: 1.1–13.6)], and high body mass index [4.5% (95% UI: 1.4–8.5)] were the three largest contributors to breast cancer DALYs globally.Conclusions: Remarkable inter-country variation exists in the burden of breast cancer. While there is a global downward trend in breast cancer age-standardised mortality rates, some countries are experiencing increases in age-standardised incidence and death rates from breast cancer. Prevention measures should be tailored to national-level estimates specific for each country and strengthened through early detection and treatment and public policy awareness campaigns aimed to reduce exposure to modifiable risk factors, particularly for countries with high incidence levels and/or increasing trends.