The number of tools used to gain a clear image of breast tissue has expanded since the introduction of standard film-screen mammography in the 1960s. Today breast imaging specialists also have digital mammography and breast ultrasound at their disposal. Research is also under way to evaluate the clinical potential of magnetic resonance imaging (MRI) and positron emission tomography (PET), as well as newer techniques.

"Healthcare professionals are always looking for improved methods for the early detection of breast cancer," says Hildegard Toth, MD, Associate Professor of Radiology and Chief of Breast Imaging. "At the Breast Imaging Center of the NYU Cancer Institute, we have dedicated and highly experienced doctors who specialize in breast imaging. That's all we do, and it's a huge advantage for patients."

Moreover, patients who have a mammogram for a suspected breast problem receive the results of the test at the time of the exam, while those who undergo routine annual screening mammograms receive the results within 30 days.

Mammography remains the "gold standard" of breast imaging. However, a recent study found that between 2000 and 2005, the rate of women undergoing regular mammograms fell by 4 percent. Dr. Toth explains that many factors may be contributing to this unfortunate statistic. Mammogram appointments are becoming increasingly difficult to obtain, possibly discouraging women from having the exam.

NYUCI's Breast Imaging Center has responded to this situation by scheduling the next breast imaging exam for each patient before she leaves the Center. "We empower our patients by giving them the ability to manage their breast health," explains Rosina Ally, Manager of Breast Imaging. The Breast Imaging Center's priority is to provide top-notch care to patients referred by NYU Cancer Institute physicians and NYU-affiliated physicians, as well as to employees and existing patients.

The Breast Imaging Center uses full-field digital mammography, enabling doctors to computer-enhance features such as contrast and brightness and to magnify the image to better scrutinize the intricacies of breast ana-tomy. Digital mammograms can be stored in hospital information systems and be transmitted electronically between medical specialists.

While a 2005 study published in the New England Journal of Medicine showed that digital mammography was more sensitive than film-screen mammography in premenopausal women and those with dense breasts, it is also recognized that the two techniques are essentially equivalent in overall accuracy. "This is an exciting time in mammography," asserts Ms. Ally. "Forty years after its introduction, we are now seeing significant advances in the technology."

One such change is tomosynthesis, an investigational approach in which X-rays are used to create a three-dimensional picture. It is conducted in a manner similar to mammography, but requires less applied compression to the breast. An X-ray tube moves in an arc over the breast while multiple images are taken during an examination that takes just a few seconds. A computer reformats the data to assemble the final 3D image. NYU does not offer tomosynthesis at this time, as FDA approval is still pending further research.

The NYUCI is involved in research assessing MRI of the breast. Last spring, the American Cancer Society recommended using mammography, ultrasound, and MRI to monitor women with an increased risk of breast cancer. At the same time, a study in the New England Journal of Medicine suggested that patients recently diagnosed with breast cancer on one side may derive benefit from preoperative MRI because of its potential for detecting cancers on the opposite side.

The NYUCI has MRI scanners with magnets of various field strengths (1.5 Tesla and 3 Tesla) used for breast imaging. MRI may be used to guide breast biopsies; to evaluate women before breast surgery; to screen women at high risk of developing breast cancer; and to evaluate the post-operative breast to look for residual tumor tissue. Researchers are studying ways to combine or fuse MRI images with PET, a test which can reveal information about a cancer's biologic behavior as well as its location.

Investigators are building a program to determine which women with ductal carcinoma in situ (DCIS, a preinvasive form of breast cancer which accounts for up to 20 percent of all lesions found on mammography) are most likely to develop invasive breast cancer, based on molecular and genetic features of the disease and imaging data obtained from NYU's 3 Tesla and investigational 7 Tesla MRI scanners. Right now, because not all DCIS lesions progress to cancer, some women receive treatment for DCIS when they may not need it.

However, MRI is not fool-proof. It has a high sensitivity for detecting breast cancers, but it may be associated with low "specificity" rates, leading to some women undergoing biopsies for benign breast disease. Because of the rate of false-positives and the generally high cost of an examination (some $2,000), MRI is not recommended as a routine breast cancer screening test for women at average risk of developing the disease.

"MRI is not yet a screening test for everyone," says Dr. Toth. "We still believe that mammography is the gold standard for early detection. But for a certain subgroup of women, MRI is going to be considered an indispensable imaging tool."

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