Impact of Treatment and Imaging Modalities on Global Breast Cancer Survival

This analysis used a microsimulation model of global cancer survival to simulate 5-year net survival for women with newly diagnosed breast cancer in 200 countries/territories in 2018, accounting for the availability and stage-specific survival impact of specific treatment modalities (chemotherapy, radiotherapy, surgery, and targeted therapy), imaging modalities (ultrasound, x-ray, CT, MRI, PET, and single-photon emission computed tomography [SPECT]), and quality of cancer care. The model was calibrated to empirical data on 5-year net breast cancer survival in 2010-14 from CONCORD-3, and evaluated the potential impact of scaling up specific imaging and treatment modalities and quality of care to the mean level of high-income countries. The analysis estimates that global 5-year net survival for women diagnosed with breast cancer in 2018 was 67.9% (95% UI 62.9-73.4) overall, with an almost 25-times difference between low-income (3.5% [0.4-10.0]) and high-income (87.0% [85.6-88.4]) countries. Scaling up a package of traditional modalities (surgery, chemotherapy, radiotherapy, ultrasound, and x-ray) as well as improving quality of care could improve global survival to 78.2% (95% UI 74.9-80.4), with a substantial impact in low-income countries, improving net survival to 55.3% (42.2-67.8). Comprehensive scale-up of treatment and imaging modalities, and improvements in quality of care could improve global 5-year net breast cancer survival by nearly 15 percentage points. Scale-up of traditional modalities and quality-of-care improvements could achieve 70% of these total potential gains, providing a more feasible pathway to improving breast cancer survival in lower-income settings even without the benefits of future investments in targeted therapy and advanced imaging.