In the US, approximately 6% of women have metastatic breast cancer (MBC) when they are first diagnosed (i.e., de novo MBC).[4]National Cancer Institute. Cancer stat facts: female breast cancer [internet publication].
https://seer.cancer.gov/statfacts/html/breast.html
[5]U.S. Centers for Disease Control and Prevention, U.S. Cancer Statistics, and National Cancer Institute. U.S. Cancer Statistics data visualizations tool: stage at diagnosis. Jun2024 [Internet publication].
https://gis.cdc.gov/Cancer/USCS/#/StageatDiagnosis
Metastatic disease was diagnosed in 260,379 (5.6%) of 4,652,885 new cases of female breast cancer reported between 2001 and 2021 in the US. Incidence of MBC has increased from 5.8 cases per 100,000 population in 2001 to 7.9 per 100,000 in 2021.[6]Centers for Disease Control and Prevention. United States Cancer Statistics: metastatic female breast cancer incidence. Nov 2024 [internet publication].
https://www.cdc.gov/united-states-cancer-statistics/publications/metastatic-breast-cancer.html
Incidence of metastatic female breast cancer is higher among non-Hispanic black women (age-adjusted incidence 11.4 per 100,000 in 2021) than among women from other racial and ethnic groups in the US (7.4 per 100,000 for non-Hispanic white women; 7.9 per 100,000 for all racial and ethnic groups combined, in 2021).[6]Centers for Disease Control and Prevention. United States Cancer Statistics: metastatic female breast cancer incidence. Nov 2024 [internet publication].
https://www.cdc.gov/united-states-cancer-statistics/publications/metastatic-breast-cancer.html
Breast cancer is most commonly diagnosed in middle-aged or older women; median age at diagnosis (all stages) in women in the US is 63 years.[4]National Cancer Institute. Cancer stat facts: female breast cancer [internet publication].
https://seer.cancer.gov/statfacts/html/breast.html
Incidence of metastatic female breast cancer rises with age, increasing from <1 per 100,000 population in women aged <40 years to 25.5 per 100,000 in women aged ≥75 years.[6]Centers for Disease Control and Prevention. United States Cancer Statistics: metastatic female breast cancer incidence. Nov 2024 [internet publication].
https://www.cdc.gov/united-states-cancer-statistics/publications/metastatic-breast-cancer.html
The breast is the most common site of cancer in women worldwide, accounting for approximately 23.8% of all new cancers in women in 2022, with highest incidence rates in Australia-New Zealand, North America, Northern Europe, and Western Europe.[7]Filho AM, Laversanne M, Ferlay J, et al. The GLOBOCAN 2022 cancer estimates: data sources, methods, and a snapshot of the cancer burden worldwide. Int J Cancer. 2025 Apr 1;156(7):1336-46.
http://www.ncbi.nlm.nih.gov/pubmed/39688499?tool=bestpractice.com
There were an estimated 310,720 new cases of female breast cancer, and 42,250 deaths from female breast cancer, in the US in 2024.[4]National Cancer Institute. Cancer stat facts: female breast cancer [internet publication].
https://seer.cancer.gov/statfacts/html/breast.html