Q&A: Global breast cancer cases expected to reach over 3.5M by 2050

New breast cancer cases in women are predicted to increase globally from 2.3 million in 2023 to more than 3.5 million in 2050. Similarly, yearly deaths from the disease are projected to surge 44% (from around 764,000 to 1.4 million deaths) with disproportionate impact in countries with limited resources. IHME Research Scientist Kayleigh Bhangdia shares the importance of this study.

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Transcript

 This transcript has been lightly edited for clarity

Q. Why was it important to undertake this study? 

A. This study was part of the greater Global Burden of Disease study, providing the most recent comprehensive global estimates of female breast cancer incidence, mortality, and DALYs, or disability-adjusted life years. We report estimates from 1990 to 2023, with forecasts through 2050, for ages 15 to 95-plus, for 204 countries and territories. And the study additionally explores six breast cancer risk factors and stratifies results by menopausal status. 

Globally, breast cancer has remained the most common cancer among females worldwide. And we know there have been advancements in diagnostics and treatments over time. However, in 2023, breast cancer remained the leading cause of cancer-related mortality among females. These estimates can be used to understand the evolving epidemiological patterns and geographical disparities in breast cancer burden over time and hopefully guide policy and strategies to reduce the burden of this disease. 

 Q. What are the key findings of the study? 

A. Our study found that there were an estimated 2.3 million new cases of breast cancer among females globally in 2023, corresponding to roughly 764,000 deaths and 24.1 million DALYs. Globally, age-standardized incidence rates increased by about 16% between 1990 and 2023, while mortality rates saw no substantial change during those years. By 2050, cases are projected to reach 3.5 million, and deaths nearly 1.4 million, with relatively constant age-standardized rates into the future. 

Here, we see age-standardized incidence rates from 1990 to 2023, with forecasts through 2050 for GBD super-regions. The high-income super-region has some of the highest incidence rates, while super-regions such as North Africa and the Middle East, South Asia, and sub-Saharan Africa have grown considerably from 1990 to 2023. We see forecasted incidence rates projected to remain relatively stable, but with sub-Saharan Africa, for example, getting much closer to the rates estimated for high-income countries.  

It’s important to keep in mind, however, how wide our uncertainty is around these projections, especially the further into the future that we’re estimating.  

Similar to the previous graph, here we have age-standardized mortality rates. We can see the opposite trends I highlighted earlier, from 1990 to 2023, with certain regions seeing clear declines or improvement in mortality, while others are seeing increases. 

We see declines in the high-income super-region as well as Central Europe, Eastern Europe, and Central Asia, while there are increases particularly in sub-Saharan Africa and South Asia. Into the future, we see relatively stable mortality rates, but notably higher rates in sub-Saharan Africa compared to the global average.  

Here we have a five-year age group on the x-axis and global 2023 age-specific counts on the y-axis. Incident cases are in blue and deaths are in red. We see the highest number of incident cases in the 50–54-year-old age group, and the highest number of deaths in 50–59-year-olds.  

But given that this is in count space, it’s likely highly reflective of demographic and population characteristics, and it will be interesting to see how the shape of this curve changes in the future as we see continued population growth and population aging impacting patterns of disease burden. 

Here we have five-year age group on the x-axis and global 2023 age-specific rates on the y-axis. Incidence again is in blue and mortality is in red. While mortality rates continue to increase with age, incidence rates are peaking in the 85–89-year-old age group. We also found roughly three times higher incidence rates among post-menopausal females, so those aged 55 or older, and four times higher mortality rates when compared to the pre-menopausal females. 

Our study also found that 28%, or roughly a quarter, of breast cancer DALYs were attributable to the risk factors we examined in the study, such as dietary risks, tobacco use, high fasting plasma glucose, and high BMI. 

Q. What notable disparities did your study uncover? 

A. When we examined results by country, income group, and geography, we saw that very different stories were unfolding. While high-income countries had the highest age-standardized incidence rates, rates were growing much faster in low- and middle-income countries. Low-income countries, in particular, saw an increase of nearly 150% from 1990 to 2023. Among higher-income countries, we also saw large improvements in the age-standardized mortality rates over time, reflecting many of the improvements in screening and treatment over the past few decades. However, it’s evident that those advances have not been equally distributed globally.  

In the map shown here, we can see global age-standardized DALY rates, colored by quintile, for female breast cancer in 2023. We see some of the highest DALY rates in sub-Saharan Africa, particularly Central and Western sub-Saharan Africa, as well as some countries in the Caribbean and Southeast Asia. 

Among lower-income countries, we actually saw increases in the age-standardized mortality rates, with nearly a 100% increase in the low-income group between 1990 and 2023, so we’re seeing this widening global health divide and a shifting disease burden to lower-resource settings, where we know that access to appropriate diagnostics and treatment for breast cancer is more limited. 

 Q. How do you hope this research will be applied to breast cancer care globally? 

A. We’ve seen improvements in breast cancer mortality achieved by higher-income countries. It’s now the responsibility of the global health community to make sure those achievements are available everywhere, giving everyone an equitable chance to survive breast cancer.  

With growing cases as a result of both demographic shifts and epidemiological transitions, and more rapidly growing incidence rates in lower-resource settings, it’s important that we invest in, and prioritize, effective diagnostic services. In addition to expanding access to appropriate radiotherapy, essential chemotherapy, and targeted medicines, expanding access and universal health coverage to encompass breast cancer care essentials, and ensuring services are not only available and accessible but also affordable, will be key.  

And lastly, our estimates will never be a replacement for the actual tracking of real-world data. It’s critical that we invest in and support high-quality cancer surveillance systems, such as population-based cancer registries, to better understand local patterns and disease burden.