An international scientific team presented estimates from 185 countries, according to which 2.3 million women will be diagnosed with breast cancer in 2022, and 670,000 will die from it. By 2050, these figures will increase to 3.2 million and 1.1 million, respectively. The researchers' findings were published in Nature Medicine.
Breast cancer is the leading cause of cancer incidence and mortality among women, and the second-highest cause of cancer incidence and fourth-highest cause of cancer mortality in the general population. To reduce the number of premature deaths from this disease globally and the survival gap in certain regions, the World Health Organization launched the Global Breast Cancer Initiative (GBCI) in 2021. Its stated goal is to reduce mortality by 2.5 percent annually, which requires early detection (more than 60 percent at stages I and II), timely diagnosis (more than 80 percent confirmed within two months of the first screening), and adequate patient management (more than 80 percent treatment completion). Implementation of this and other programs requires accurate data on the current disease burden and its future projections.
Miranda Fidler-Benaoudia of the University of Calgary and colleagues from Australia, Canada, Kenya, the United States, and France estimated breast cancer incidence and mortality in 185 countries for 2022 and 2050 using the International Agency for Research on Cancer (IARC) GLOBOCAN database and 10-year incidence trends from the CI5plus database and mortality data from the WHO. These estimates were provided globally, as well as regionally and by specific age groups; cases in men were not included.
According to researchers' calculations, in 2022, 2.3 million new cases of breast cancer developed in 185 countries, and 670,000 deaths occurred from it. This tumor occupied the first or second place in the structure of oncological incidence in 183 countries and mortality in 169 countries. Moreover, its burden in different regions of the world was very uneven and could vary by almost fourfold. The number of new cases was highest in Australia and New Zealand (100.3 per 100,000), followed by North America and Northern Europe, and the lowest in South and Central Asia (26.7 per 100,000), East and Central Africa. In terms of mortality, the leading regions were Melanesia (26.8 per 100,000), Polynesia, and West Africa, and the lowest rates were in East Asia (6.5 per 100,000), Central and North America.
The mortality-to-incidence ratio tended to increase with decreasing human development index (HDI) scores: from 17 percent at very high HDI levels to 56 percent at low HDI levels. It is estimated that, on average, one in 20 women will be diagnosed with breast cancer during her lifetime, and one in 70 will die from it. If current trends persist, by 2050, the number of new cases of this cancer will increase by 38 percent to 3.2 million, and deaths from it will increase by 68 percent to 1.1 million.
Of the 50 countries with high-quality CI5plus data for at least the past 10 years, the incidence of new breast cancer cases increased in 27 (54%) over this period. The largest annual increases were observed in Bahrain (4.8%), South Korea, and Japan, while in the under-50 age group, the largest increases were observed in Ecuador (4.1%), Slovenia, and Croatia. Significant declines were recorded in only three countries—Argentina, Germany, and Denmark—and only in those aged 50 and over. Of the 46 countries with high-quality 10-year mortality data, 30 saw a decline. Seven countries achieved the GBCI target of a 2.5% annual mortality reduction: Malta (3.8%), Denmark, Belgium, Switzerland, Lithuania, the Netherlands, and Slovenia. Rates between 2.1 and 2.4 percent were also recorded in Norway, Sweden, Ireland, Australia, the United Kingdom and New Zealand.
Thus, the dynamics of breast cancer incidence and mortality from it vary greatly across different regions of the world, and despite the targets set by the WHO, these indicators will increase, mainly due to countries with medium and low HDI levels, where the greatest effort is needed to combat the disease, the authors of the study conclude.
An earlier analysis of IARC data for the same 185 countries showed that by 2050, overall cancer incidence will increase by 77 percent, and mortality by 90 percent.
