House Call: Mammography Is Essential for Breast Cancer Screening

The gold-standard imaging technique for breast cancer screening is mammography, which uses low-dose x-rays to detect tumors. But some companies are advertising screening with another technique, thermography, instead of mammography. However, the U.S. Food and Drug Administration (FDA), which regulates medical devices, has not approved thermography as a stand-alone tool for breast cancer screening. In fact, the FDA has issued a consumer advisory about the dangers of thermography-only screening.

Thermography, which shows temperature changes on or just below the surface of the skin, is FDA-approved for breast cancer screening only when used with mammography. Although some companies claim that thermography is a proven alternative to mammography, there is no evidence to support these claims.

Beware of misleading ads

According to the FDA’s consumer advisory, misleading ads on some Web sites promote thermography as equal to or better than mammography for breast cancer screening. The FDA’s consumer advisory was first issued in 2016 and updated in 2017 after the FDA issued warning letters to two companies that falsely advertised thermography as an effective breast cancer detection tool.

Thermography was not the first unproven technique to be advertised as a replacement for mammography for breast cancer screening. In 2013, the FDA issued a consumer advisory about companies that advertised nipple aspirate (also called ductal lavage) tests for breast cancer screening. In a nipple aspirate test, suction is used to remove a small amount of fluid, which is tested for abnormal cells that can indicate cancer. One company advertised the test as a “Pap test for breast cancer,” comparing the nipple aspiration test
 to the Papanicolaou test for cervical cancer. This comparison was deceptive because nipple aspirate tests—which often find abnormal cells in patients who do not have cancer or find no abnormal cells in patients who have cancer—are much less reliable than Pap tests. Like thermography, nipple aspirate tests have never been proven to be an effective stand-alone breast cancer screening tool.

Companies that promote unproven techniques for breast cancer screening pose several risks to patients. Patients are at financial risk because insurance companies are unlikely to cover a procedure that is used for a purpose that is not approved by the FDA. But even more important is the risk to the patients’ health.

“The greatest danger of these un-proven screening techniques is that they may miss cancers that could have been detected with mammography and treated at an early stage with a good chance of cure,” said Therese Bevers, M.D., a professor in the Department of Clinical Cancer Prevention at The University of Texas MD Anderson Cancer Center.

Get appropriate screening

Both the National Comprehensive Cancer Network (NCCN) and MD Anderson recommend annual breast cancer screening with mammography and a clinical examination (in which a doctor or nurse checks for lumps or other changes) for women 40 years or older with an average risk of the disease. “We know that annual screening with mammography can detect breast cancer and save lives,” Dr. Bevers said. She added that no major cancer centers or national organizations making breast cancer screening recommendations (such as the NCCN, U.S. Preventive Services Task Force, or American Cancer Society) endorse thermography for breast cancer screening or diagnosis.

Women of any age who have a higher than average risk of breast cancer may need more frequent screening examinations or additional tests such as magnetic resonance imaging. The screening guidelines for women with higher than average risk vary according to women’s age and risk factors.

Women who are unsure about their risk for breast cancer can use the U.S. National Cancer Institute’s online breast cancer risk assessment tool (www.cancer.gov/bcrisktool). Dr. Bevers said that the results from the risk assessment tool are useful but should not be considered a substitute for a physician’s advice.

“A woman’s doctor can help determine the patient’s risk of breast cancer and recommend an appropriate screening plan,” Dr. Bevers said. “And mammography is still the gold standard for breast cancer screening.” 

For more information, ask your physician, call askMDAnderson at 877-632-6789, or read MD Anderson’s breast cancer screening guidelines at http://bit.ly/1kln5fj.

OncoLog, January 2018, Volume 63, Issue 1