The Mammogram Debate Continues

The Wall Street Journal’s article, published this morning, Final Recommendations on When to Start Getting a Mammogram, continues the trend of highlighting the risk of under screening while mitigating the harms of overtreatment in the mammogram debate.

The article does a good job explaining that right now three different advisory groups, the American College of Obstetricians and Gynecologists (ACOG), the U.S. Preventative Services Task Force (USPSTF), and the American Cancer Society, have different recommendations for when women of average risk should commence mammograms, how often the mammograms need to be done and at what age women should cease doing routine, preventative mammograms. 

"Final Recommendations on When to Start Getting a Mammogram" published by the Wall Street Journal

However, the article really drops the ball when it comes to explaining the origin of these different recommendations. The article explains that the controversy is centered on the balance of doing enough screening to save women’s lives, while not over-screening which leads to false positives and unnecessary treatment. One of the physicians quoted in the article, Dr. Therese Bevers, chairwomen of the breast cancer screening and diagnosis guidelines panel for the National Comprehensive Cancer Network, stated, “Harms such as false positives requiring a repeat ultrasound or a needle biopsy are outweighed by the potential for lives saved.” This is short sighted. If overtreatment were just about ultrasounds and needle biopsies, there simply would not be any controversy. The controversy stems from a combination of (i) false positives which can lead to emotional stress, financial strain due to follow-up testing and sometimes unnecessary, invasive procedures including mastectomies, and (ii) catching early stage, or “stage zero” cancers such as Ductal Carcinoma In Situ (DCIS), which no one really knows how to appropriately treat.

DCIS refers to clusters of abnormal cells confined to milk ducts which may later develop into an invasive breast cancer. Before the implementation of widespread mammography in the 1980’s, DCIS accounted for just 3% of breast cancers diagnosed. Now DCIS accounts for nearly a third of breast cancer diagnoses annually. It was thought that treating DCIS (and it is treated the same as breast cancer, typically with lumpectomy and radiation) would cause the rates of invasive breast cancer to plummet, but the data has failed to support this hypothesis. Everyone agrees that some cases of DCIS will eventually become an invasive breast cancer, but the exact proportion is widely debated. The data is causing many prominent physicians and researchers such as Dr. Laura Esserman, a breast surgeon at the University of California, San Francisco, to question whether DCIS is in fact a risk factor for invasive cancer rather than a precursor. Dr Esserman believes that for some women a more effective treatment to decrease the risk of developing invasive breast cancer in the future may be hormonal or immunological therapies.

 The future will bring more information about how to best interpret and treat DCIS but at the moment the issue is not a question of data interpretation but rather a matter of individual risk tolerance. Each woman must decide whether she feels more comfortable having mammograms earlier and more frequently, which may save her life but also puts her at higher risk for potentially unnecessary, costly treatment and all the baggage that comes with that treatment (anxiety, for example) or limiting mammograms to when they are more likely to be beneficial, but then possibly missing cancer in its early stages. One of the physicians, Dr. Nancy Keating, quoted in the article says that she tries to give patients an idea of whether they are at average or above average risk for developing breast cancer and lets them know the pros and cons of getting mammograms early and often. The patients are then able to make an informed decision about how to proceed. That sounds about right.