Bottom line: Mammograms save lives

By Matthew Gromet

Breast cancer can be a woman’s biggest fear and these days it’s also one of the most confusing health issues she faces.

On May 3, another study was published in the Journal of the National Cancer Institute (JNCI) stating that average-risk women under the age of 40 should not get screening mammograms due to the low incidence of cancer in that age group. This finding is consistent with guidelines of mainstream medical organizations.

What has departed from current guidelines, however, is November’s U.S. Preventive Services Task Force recommendation that women ages 40-49 no longer need breast cancer screenings, and that women 50 or older need screening only every other year. Headlines continue to create confusion in the minds of women and their doctors about the benefits of mammograms.

Women’s health care is already paying the price. An Avon Foundation survey reports that 10 states are reducing cancer screening services for women under 50. In February, the Annals of Internal Medicine published a poll indicating that 67 percent of physicians would stop advising women in their 40s to get routine mammograms and that 62 percent would advise only every other year mammograms for women over 50.

As a radiologist who has practiced breast imaging for 26 years in one of the nation’s largest mammography programs, I’ve researched the Task Force’s recommendations and found serious flaws in its methods and conclusions.

What’s wrong with the research method?

The Task Force — which included no breast cancer specialists — conducted no original research. It used only statistical and computer models to estimate screening benefits at various ages. The “gold standard” for medical research is a randomized double-blind study measuring actual outcomes, not estimates. Multiple studies worldwide that meet this gold standard have shown significant mortality reduction from screening women age 40-49. The U.S. breast cancer death rate has declined by 30 percent since 1990 when screening mammography was introduced. As compliance with current guidelines increases, mortality rates should drop further. Why reverse this encouraging trend?

What’s wrong with the data?

The data cited by the Task Force included outdated research from the 1960s that was not structured to measure benefits to women in their 40s. Some studies had multiple flaws including poor mammography techniques. One major study allowed improper placement of patients with advanced breast cancer into the screened group, skewing the results.

Despite their flaws, these less relevant studies still showed a 15 to 24 percent lower mortality for women in their 40s. While noteworthy, this benefit is less than that found in other studies using improved methods. For example, a large Swedish study, published in the medical journal The Lancet in April 2003, showed a 48 percent reduction in mortality from breast cancer for women who were screened in their 40s.

The studies cited used film, not digital, mammography, which is now in widespread use. Although the Task Force acknowledges digital’s proven higher detection rates in women under 50, it then states that “it is not clear whether this additional detection would lead to reduced mortality from breast cancer.” Where is the common sense here?

What about risk factors?

About 75-80 percent of women diagnosed with breast cancer have no family history of the disease. If we followed the Task Force suggestion that women in their 40s be screened only if they have risk factors, we would miss the great majority of breast cancers.

The Task Force highlighted the harms and ignored the benefits. It measured only one benefit of screening mammograms — decreased mortality. But early detection of cancer — the purpose of screening — is important for reasons beyond the lives it saves. For cancers detected early, surgery is less drastic and usually allows for preservation of the breast. Also, there are fewer cases of lymph node involvement and the need for chemotherapy.

The harms cited by the Task Force and the JNCI studies included anxiety, false-positive results and unnecessary biopsies. In reality, only about 10 percent of patients are recalled and most of them then receive normal results. A biopsy that doesn’t show cancer is benign, not “unnecessary.”

What should women do?

For decades researchers have conducted randomized clinical studies and their findings have proven significant mortality reduction in women over 40 who get mammograms. And while early detection saves lives, it also saves health care dollars by detecting cancer at an earlier, more treatable stage. The American Cancer Society and many professional groups stand firm in support of established guidelines that women 40 and over should get annual mammograms. Mammography remains the only proven way to save lives by finding breast cancers early.

Dr. Matthew Gromet is a physician at Charlotte Radiology, P.A., in Charlotte, subspecializing in breast imaging.