Breast imaging is an important part of the work of Dr. Margie Brown, Dr. Marta Kenney and Dr. Kimberly Stigers, who work at the Saint Joseph Breast Center.
“The goal of a breast imager is to diagnose breast cancer when it can be treated successfully, ideally at an early stage,” said Dr. Brown. “Although anecdotal reports of cancers regressing on their own exist, until we find a reliable means of prospectively identifying them, the current standard of care is treatment of all noninvasive and invasive breast cancers.”
Mammography’s contribution to the decrease in breast cancer mortality has been debated for several years. The most recent reanalysis of the Swedish Two-County Trial, which followed 130,000 women for almost 30 years, documented a 30-percent risk reduction over a 25-year period.
Dr. Kenney said diagnostic radiologists often rely on more than standard mammography to ascertain a diagnosis. “Cancer may present on imaging in a variety of ways,” she said. “Calcifications, specifically linear/branching, heterogeneous or amorphous in clustered, linear or segmental distribution, are the hallmarks of ductal carcinoma in situ (DCIS).”
Invasive cancers present as masses, areas of architectural distortion or new focal asymmetries, Dr. Kenney said. “The difficulty in interpretation lies in the fact that only some cancers have a ‘classic’ appearance,” she said. “There is considerable overlap between features of cancer and benign entities. For this reason, ultrasound and MR (magnetic resonance) are frequently used as adjuncts to mammography.” (See the article on MRI testing in this issue.)
“Mammography is the gold standard for screening average-risk women,” Dr. Brown said. “For women with elevated risk, research supports the addition of screening MR, although a decrease in mortality has not yet been documented. MR screening is reserved for those whose lifetime risk exceeds 20 percent. New technologies, such as tomosynthesis and molecular imaging, may play a role in future breast cancer detection.”
Dr. Stigers addressed the question about which patients should be screened with mammography. “Despite recent media controversies, there is agreement among most major medical organizations, including the American Cancer Society, the American Medical Association and the American College of Radiology,” she said. “Annual screening mammography should begin at age 40 and continue as long as a woman’s life expectancy exceeds five years. Regardless of age, personal history of DCIS, invasive breast cancer, lobular neoplasia, atypical ductal hyperplasia (ADH) or ovarian cancer should prompt annual mammography. BRCA mutation carriers and others with a lifetime risk of 20 percent or greater are advised to start mammography at age 30.” In addition, women who received mantle radiation between the ages of 10 and 30 should begin screening eight years after XRT, but not before the age of 25.
“We have been alarmed at the advertisements in lay literature promoting thermography making claims such as, ‘Breast screening without radiation! Without Pain! FDA Approved!’” Dr. Kenney said. “In fact, the Food and Drug Administration is concerned that women will believe these misleading claims about thermography and will not receive needed mammograms.”
In June 2011, the FDA issued the following safety communication: “Thermography is not a replacement for screening mammography and should not be used by itself to diagnose breast cancer. The FDA is not aware of any valid scientific data to show that thermographic devices, when used on their own, are an effective screening tool for any medical condition.”
By Julie Griffith