Distance Decides Diagnosis: Breast Cancer Clusters Reveal Hidden Care Gaps

A geospatial study of breast cancer diagnoses in northern Tanzania links lower detection rates to where diagnostic services are available—not to where the disease is more common. Researchers mapped the home subdistricts of 379 women diagnosed with breast cancer at Bugando Medical Center (BMC) in Mwanza between July 2019 and December 2023. Diagnosis rates clustered around the tertiary hospital, while lower-rate areas clustered toward the distant edge of BMC’s catchment. Because BMC is the only facility in the region offering comprehensive breast cancer care, the authors argue its patient “geographic fingerprint” shows who can reach diagnostic testing. The analysis covered 45 subdistricts and used Global Moran’s I and Anselin Local Moran’s I.