Breast cancer is the most common kind of cancer in women, and the leading cause of cancer death for women worldwide, with nearly half a million deaths every year.
Statistics on Metastatic Breast Cancer are hard to find. Below is a small collection. More will be added over time.
Causes: Metastasis happens despite vigilance and precautions. Healthy lifestyles, timely screening and early detection are no guarantee a person will not metastasize. Even stage 0 patients metastasize.
Frequency of Progression: In developed countries, including the US, at least 30 % of women with early stage breast cancer will eventually develop metastatic breast cancer. (2008 Global Survey by Pfizer Oncology) NOTE: Some reporting puts this number at 40%. Both statistics exclude those initially presenting with metastatic breast cancer.
Stage at Diagnosis: In the METAvivor ABC1 Study, 19% of respondents were initially diagnosed at stage 0 (4%) or stage 1 (15%). Of note, slightly more stage II patients metastasized than stage III patients.
Number Initially Diagnosed at Stage IV: In the METAvivor ABC1 Study, 31% of respondents, who were initially diagnosed at stage IV, had no previous diagnosis of breast cancer.
Number Diagnosed with MBC: It is not known how many Americans are diagnosed annually with metastatic breast cancer because there has never been a count of people progressing to the disease. The count has been limited to people initially diagnosed at stage IV who had no history of breast cancer. HOWEVER, the number has been estimated to be as high as 73,000 to 86.000. (Silent Voices)
Number Living with MBC: The number of Americans living with metastatic breast cancer is not known. The numbers not collected. METAvivor has been pushing to have a count made and it appears that a such a system may be developed to do that in 2013.
Long-Term Survival: It is estimated that 2-3% of persons with the disease actually survive the disease. There have been few studies done on long-term survival for MBC. It is possible that the percentage is somewhat higher.
Median Survival: Median survival is 2 - 3 years; however, it is not uncommon to meet people 15 years out and doing well.
Mortality Rate: New treatments extend life for some, but survival remains elusive. Over 40,000 women and men have been dying annually since 1987.
Mortality vs Research: 100% of breast cancer deaths are caused by metastatic breast cancer. The reference to 90% refers to deaths is an average that pertains to all cancers. One cannot die of breast cancer that has not metastasized and spread. Despite the fact that metastasis causes almost all cancer deaths, only 2% of research funds go toward stage IV cancer research.