By Jeffrey T. Jensen, MD, MPH

Leon Speroff Professor and Vice Chair for Research, Department of Obstetrics and Gynecology, Oregon Health & Science University, Portland

Dr. Jensen reports he is a consultant for and receives grant/research support from HRA Pharma, Bayer Healthcare, Merck, Agile Pharm, Population Council, AbbVie, Evofem, and ContraMed; and is a consultant for Teva Pharmaceuticals and MicroChips.

Synopsis: In the United States, the costs associated with the management of false-positive mammograms and breast cancer overdiagnosis is estimated to be $4 billion each year.

Source: Ong MS, Mandl KD. National expenditure for false-positive mammograms and breast cancer overdiagnoses estimated at $4 billion a year. Health Affairs 2015;34:576-583.

In an effort to better define potential harms associated with breast cancer screening, the authors used expenditure data from a major national U.S. healthcare insurance plan (not further identified) to identify costs of false-positive mammograms and breast cancer overdiagnoses in the 12 months following mammography screening. The study cohort included all female beneficiaries of the plan between the ages of 40-59 years who underwent a routine screening mammography during 2012 and who remained covered

by the plan during the next 12 months. Women considered to be at high risk for breast cancer or those with a previous personal diagnosis of any breast disorder or cancer were excluded. Mammography screening outcomes were assessed separately for the age groups 40-49 and 50-59. Two primary outcomes were identified: false-positive mammograms and screen-detected breast cancer (invasive breast cancer and ductal carcinoma in situ [DCIS]). A false-positive mammogram was defined as a study that led to further diagnostic workup that was not followed by a breast cancer diagnosis. The authors used a published estimate of 22% to determine the number of screen-positive women diagnosed with breast cancer who were likely to have received an overdiagnosis. Costs were defined as the total amount paid by the insurer for the claim related to the diagnosis.

Excluding screening cost, the average claims expenditure per false-positive mammogram was $852 and the average out-of-pocket expense was $200. The average cost of medical services for each invasive breast cancer diagnosed was $51,837 (out-of-pocket $3019). For DCIS, the average treatment cost was $12,369. One-third of women diagnosed with invasive breast cancer underwent total mastectomy.

Using these estimates, the authors calculated that the overdiagnosis of invasive breast cancer and DCIS ($1.2 billion) and workup of false-positive mammograms ($2.8 billion) cost the U.S. healthcare system $4 billion each year.


“First do no harm” remains one of the most important principles of medicine. Technological advances continue to increase healthcare costs and put the squeeze on clinicians. Although we want the best for our patients, we need to consider how to get the best bang for our healthcare dollar. With the cost of mammography a covered benefit under most insurance plans, most of us follow the ACOG and American Cancer Society recommendation to start annual screening at age 40. This new study, published in a health economics journal, provides additional information to use when you discuss this screening strategy. Although there are weaknesses associated with a retrospective analysis of insurance claims, the use of actual claims paid by a national private insurance plan provides a realistic estimate. The figure of $4 billion as the cost associated with unnecessary breast cancer treatment and the workup of false-positive screening mammograms should at least raise your eyebrows.

Of particular significance, the costs associated with breast cancer overdiagnosis appear higher in women aged 40-49. The U.S. Preventive Services Task Force (USPSTF) recommends against routine screening mammography in women age 40-49 years, concluding that the risk of harm attributable to screening exceeds the potential benefit for low-risk women.1 Mammography for women age 50-74 years is recommended, but only every 2 years and the USPSTF concluded that the evidence of additional benefits and harms of screening mammography in women 75 years or older was inconclusive.

Although the costs and burden of a false-positive mammogram are considerable, the overdiagnosis of breast cancer carries the additional risk and expense of unnecessary surgery and medical treatments. Data to support the concept of overdiagnosis include the landmark paper from Bleyer et al published in the New England Journal of Medicine2 that documented that 30 years of screening mammography was associated with a doubling in annual detection of early-stage breast cancer but only an 8% decrease in the diagnosis of late-stage breast cancer. The overdiagnosis estimate of 22% comes from the 25-year follow-up of the mammography randomized trial done in Canada.3

As estimated in a previous column, according to the 2010 census, there are more than 52 million women aged 40-65 years, and the cost of a universal program for screening mammography for this group is almost $14 billion annually. We can now add to this the $4 billion cost associated with management of false-positive studies and the overdiagnosis of early breast cancer.

We can expect to see additional recommendations from the USPHTF and these may influence insurers to change their coverage of mammogram screening. Rather than oppose these recommendations, we need to lobby to ensure that any savings are redirected to research leading to the discovery of advanced diagnostic modalities that can identify women truly at risk for serious breast cancer.


  1. U.S. Preventive Services Task Force. Screening for breast cancer: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med 2009;151:716-726, W-236.
  2. Bleyer A, Welch HG. Effect of three decades of screening mammography on breast-cancer incidence. N Engl J Med 2012;367:1998-2005.
  3. Miller AB, et al. Twenty-five year follow-up for breast cancer incidence and mortality of the Canadian National Breast Screening Study: Randomised screening trial. BMJ 2014;348:g366.