Breast Cancer Screening: Facts and Figures
In 2015, it was estimated that there would be 231,840 new breast cancer cases in the United States and roughly 40,290 women would die of the disease.
A woman in the United States has a one in eight risk, over the course of her lifetime, of being diagnosed with breast cancer.
The incidence of breast cancer increases steadily with age. Each year approximately 1 woman in 1000 will be diagnosed with breast cancer at the age of 40, increasing to approximately 1.1/1000 at age 41, 1.2/1000 by age 43, etc. This increases to 2/1000 by age 50, 2.1/1000 by age 51, up to 3/1000 by age 60 and so on.
None of the parameters of screening change suddenly at the age of 50 or any other age.
There is no scientific or biological reason to delay screening until the age of 50. No decade of life 40-49, 50-59, 60-69, or 70-79 accounts for more than 25% of the cancers diagnosed each year. Some analysts have compared women in one decade of life (ages 40-49) to the combined results for all other women (ages 50-79) to make it appear as if there is a sudden increase in results at the age of 50. However, there are no sudden jumps.
It has been known for years that mammographic screening is able to detect a large percentage of breast cancers before they can be felt and when they are at a smaller size, earlier stage, and more likely to be curable
The breast cancer death rate was unchanged for decades prior to the onset of mammography screening, which began at a national level in the mid 1980's. As expected, five-to-seven years later, the death rate began to fall in 1990, and has now declined by over 30% since then. Each year, more than 30% fewer women die from breast cancer than would have died had the death rate not been reduced. Therapy has improved, but lives are saved when breast cancers are detected and treated earlier. It has been shown in studies from the Netherlands, Sweden, Norway and the United States that even when women have access to the latest therapy, it is screening that leads to the greatest reduction in deaths.
Men develop breast cancer as well and receive the same modern therapy as women, but the death rate for men has decreased only slightly since 1990. This is because men are not screened and do not have the benefit of early detection.
Breast cancer has a disproportionately devastating impact on minorities. In 2010, breast cancer mortality rates were 41% higher among African-American women than among non-Hispanic white women. This is, in part, due to lower participating in breast cancer screening.
The most rigorous scientific studies known as randomized-controlled trials (RCT) have shown a decline in deaths from screening women beginning at the age of 40.
More than 40 percent of the years of life lost to breast cancer are among women diagnosed in their 40s.
The harms of screening are negligible compared to dying from breast cancer. For every 1,000 women screened, 100 are recalled. Of the 100, 81 are either called negative and rescreened in a year or have another imaging study in six months. Nineteen undergo a minimally invasive needle biopsy, and five of them are diagnosed with breast cancer.
Major health organizations, including the American Cancer Society, the American Society of Breast Disease, the American College of Obstetricians and Gynecologists, the American College of Radiology and the Society of Breast Imaging, recommend annual mammograms beginning at age 40.
Dr. Esmaili is a mammogram expert witness and a medical director of a breast care imaging center in southern California. Contact us at mammogramexpert.com or firstname.lastname@example.org for a case consultation.