By ecancer reporter Romany Armstrong

Breast cancer mortality rates are disproportionately higher in low- to middle-income countries (LMIC) than in high income countries (HIC), finds a recent Nature study.  

Lack of access to healthcare facilities, delays in diagnosis and treatment initiation, as well as financial setbacks, prevent women from seeking lifesaving treatments during the early stages of breast cancer. 

Breast cancer is the leading cause of cancer-related death in women and, even with gender categories combined, it is the second most common and fourth most common cause of cancer-related mortality. 

Although a global issue the burden is not evenly distributed and while breast cancer incidences are higher in HICs, it is LMICs that suffer from a greater proportion of breast cancer-related deaths. 

In sub-Saharan Africa fewer than 40% of breast cancers are caught in the early stages. Most disease cases are diagnosed in the late stages with 26% already having progressed to metastasis, this decreases likelihood of successful treatment. 

Social situation also plays a part as diagnosis and treatment are expensive and women in LMICs often do not have control over household finance.   

These factors, combined with low treatment capacity, limited trained medical professionals, shortages of radiotherapy treatment facilities and chemotherapy medicines contribute to poor survival and highlight inequality. 

As LMICs develop, breast cancer incidence is expected to rise due to increased life expectancy and exposure to risk factors.

Therefore, it is essential to get healthcare infrastructure in place ready or these countries could be disproportionately impacted.  

Low cost and implementable alternatives, such as clinical breast examination could see a rise of early-stage diagnosis from around 40% to 63%.

This is not far off the predicted 69% increase that could be achieved through expensive mammography machines and therefore improves survival at modest cost.  

Early detection is essential in reducing mortality. Following the implementation of screening programs in Argentina, Germany and Denmark between 2008 and 2017, incidence rates in women aged 50 and over decreased.  

Overall, the study shows that breast cancer incidence rates are rising for women of all ages but there has been a significant rise for women aged under 50 years in 24 countries, most of which are HICs. 

These rises are linked to increased oestrogen exposure due to fewer pregnancies, older maternal age, less breast feeding, obesity, physical inactivity, alcohol consumption, and hormonal contraception or replacement therapy. 

An estimated 1 in 4 breast cancer cases could be prevented through increasing public health awareness to encourage healthy lifestyles, promoting non-hormonal medicine alternatives, and by supporting breast feeding mothers.  

Initiatives that could help are increased tax on alcohol, tobacco, unhealthy food and drinks, but also by changing transport infrastructure to encourage walking and cycling and investing in maternity leave. 

At the current rate, by 2050, there is projected to be a 38% rise in cases and a 68% rise in deaths.

Only 7 of the most developed countries worldwide have met the GBCI goal of 2.5% annual decrease in mortality rates.

The authors note that if all countries met this goal from 2022 onwards the number of breast cancer-related deaths could be halved.

Reference: Kim, J., Harper, A., McCormack, V. et al. Global patterns and trends in breast cancer incidence and mortality across 185 countries. Nat Med (2025). https://doi.org/10.1038/s41591-025-03502-3