New mammography recommendations could be harmful

By John Benson, Special to the BDN
Posted Nov. 24, 2009, at 6:05 p.m.

I am a board certified radiologist and I have practiced breast imaging for over 30 years interpreting tens of thousands of mammograms and performing hundreds of breast interventions. I regularly diagnose cancer in women who miss their annual screening exam and come in a year or more later. I diagnose cancer in 40- to 49-year-old women on a regular basis.

Contrary to what the new federal task force recommendation would have us believe, there is no sudden biological event that happens at a woman’s 50th birthday that makes them more likely to develop a lethal cancer. Cancer risk increases with age but it is gradual.

Since digital mammography is now in widespread use, more cancer is being diagnosed especially in women under 50. For example, the cancer detection rate at our institution increased four-fold after digital mammography. Most of this increase is early, highly curable cancer in younger women. Recent published reports demonstrating this effect were excluded by the government panel.

When I see a case of advanced cancer it is usually in a patient who has not had a screening. I can tell you without reservation that I will be seeing more advanced cancers if women delay screening until age 50 and follow the recommendation to come in at a two-year interval instead of annually.

Once again, women are the victims of confusing guideline switching regarding breast cancer screening. It is particularly distressing that this comes at a very exciting time in breast cancer treatment and diagnosis with the advent of targeted cancer treatments based on genetic susceptibility and advances in breast imaging including an increasingly pervasive use of digital mammography, ultrasound, MRI and molecular or functional breast imaging. Selective use of new diagnostic methods enhances accuracy and can lower the false positive rate referred to in the panel’s report.

The government’s panel of experts in public health and health statistics, after a highly focused review of selected evidence, is now retracting their earlier recommendation that screening for breast cancer begin at age 40. It is interesting to note that none of the panel members are experts in breast imaging, breast surgery or oncology.

The long-standing recommendation that all women undergo annual mammography beginning at age 40 has detected many early stage cancers and has prevented many deaths. Many studies have shown as much as a 30 percent mortality reduction from breast cancer since the mid-1980s, when widespread screening mammography was introduced. Organizations such as American Cancer Society, American College of Radiology, American Academy of Obstetrics and Gynecology, National Cancer Institute, breast cancer advocacy organizations and prestigious cancer institutions such as MD Anderson and Mayo Clinic have reacted swiftly and in many cases with justifiable outrage over these new recommendations.

A review of the panel’s methodology notes hundreds of peer-reviewed studies were excluded from the decision-making process. Many of these excluded studies indicate significant mortality reduction in screening participants in the 40 to 49 age group. By the panel’s own admission, there is evidence for mortality reduction in this group but they impose an arbitrary benefit threshold and conclude there simply are not enough lives saved to justify continuing to screen this population.

The American Cancer Society is widely known for its carefully formulated recommendations. It used fundamentally the same data to arrive at a totally opposite conclusion, that there is clear life saving value in screening the 40 to 49 age group. It is also interesting to observe that evidence cited by the task force is basically the same it used in 2002 to issue their landmark recommendation to include the 40 to 49 group for screening mammography. This flip-flop does not give a sense of confidence in what is supposed to be the role model for guideline setting.

The panel is careful to indicate these new recommendations are for women of average lifetime risk of developing breast cancer. This reasoning is counter-intuitive because it is well-known that only 25 percent of breast cancer is diagnosed in women with a positive family history.

I strongly encourage women to continue to participate in the proven, life-saving practice of annual screening mammography beginning at age 40.

John Benson, M.D. is the medical director of the Breast Center at Mount Desert Island Hospital in Bar Harbor and is a Fellow of the American College of Radiology.

http://bangordailynews.com/2009/11/24/opinion/new-mammography-recommendations-could-be-harmful/ printed on July 31, 2014