Technology Overview
This article appeared in Imaging Technology News, November/December 2008 Issue

MBI Takes On FFDM

Molecular breast imaging rivals FFDM for dense breasts, but will it be readily adopted?
By: Antonio Garcia, industry manager, Medical Imaging Group, Frost

CAD Could Improve Cancer Detection Rate in Mammography

Researchers found that, “Single reading with computer-aided detection could be an alternative to double reading and could improve the rate of detection of cancer from screening mammograms read by a single reader,” in a recent study published in the October issue of The New England Journal of Medicine.

The study was a prospective, multi-center clinical trial, comparing the cancer detection rate for single reading of screening mammograms with CAD input versus double reading without CAD support. Researchers used Hologic’s R2 computer-aided detection (CAD) system in the study.

Interpretation by two readers (double reading) rather than one reader is known to improve the cancer detection rate. The study’s authors said, “Where single reading is standard practice, computer-aided detection has the potential to improve cancer detection to the level achieved by double reading.”

In the study, lead author Fiona Gilbert, M.D., and her colleagues in the United Kingdom analyzed the screening results from 31,057 women undergoing routine screening by film mammography and found that a single reader with Hologic’s R2 CAD system produced comparable cancer detection rates (87.2 percent) to double reading (87.7 percent) without CAD. Although single reading with CAD produced a higher recall rate (3.9 percent) than double reading (3.4 percent), they concluded that despite this difference, “Single reading with computer-aided detection could be an alternative to double reading and could improve the rate of detection of cancer from screening mammograms read by a single reader.”

“Double reading is a method for increasing cancer detection commonly used in European screening programs. However, it is used by few practices in the U.S. because it is time-consuming and because of a shortage of radiologists focused on breast imaging,” said Ronald A. Castellino, M.D., FACR, chief medical officer for Hologic. “These results indicate that in the United States, where single reading of mammograms is most common, Hologic’s R2 CAD system can provide an improvement in cancer detection rates comparable to those achieved with double reading. This important study, combined with prior published research studies, further supports the use of the R2 CAD system to increase cancer detection.”

For more information: www.hologic.com


X-ray mammography is considered the “gold standard” for breast cancer screening in the breast imaging equipment market. The procedure is generally seen as the most effective option for women needing a diagnosis of any abnormalities in the breasts. However, with recent advances in other diagnostic breast cancer tests, such as breast MRI and molecular breast imaging, mammography may slip from its golden status.

These photos provided by the Mayo Clinic show dense breasts, which mammograms don't penetrate well. The left image is a 50-year-old's digital mammogram, showing no problems. The right image is that same woman's MRI, showing what turned out to be an early
These photos provided by the Mayo Clinic show dense breasts, which mammograms don't penetrate well. The left image is a 50-year-old's digital mammogram, showing no problems. The right image is that same woman's MRI, showing what turned out to be an early



Widespread Application

Mammograms aren’t necessarily the most effective but rather, the most available method for diagnosing breast cancer. While the analog segment in mammography continually declines in revenue growth – revenues are based on manufacturer revenues from sales of equipment to hospitals, private radiology practices, clinics and imaging centers – substantial growth is seen in full-field digital (FFDM) X-ray mammography, which is still a driver in this segment. Indeed, according to Frost & Sullivan’s discussions with hospital facility procurement officers, FFDM is certainly deemed a “priority” purchase in 2009.

The total North American breast imaging equipment market was $910.3 million in 2007. X-ray mammography contributes to 67 percent of this figure, and is expected to maintain this healthy dominance in the total breast imaging market going forward.

However, given recent trends and the results of some highly anticipated studies, mammography may at some point yield to some more sophisticated – and more accurate – methods for detection of cancers in women.

New Rivals to Mammography

Granted, mammography has its competition: breast magnetic resonance imaging (MRI), nuclear breast imaging and breast ultrasound. However, new promise is seen in molecular breast imaging (MBI), a new experimental method that is currently in advanced testing at the Mayo Clinic in Rochester, MN. MBI reveals more tumors and gives fewer false positives, when compared to mammography.

In the largest study ever to compare MBI to mammography, researchers have shown that MBI can detect three times as many cancers in women who have dense breast patterns (as seen on pg. 37) and are at increased risk of breast cancer (due to personal or family history or a previous precancerous condition).

In the MBI procedure, women are given an intravenous dose of a short-acting tracer that is absorbed more by abnormal cells than by healthy ones. Special cameras then collect the “glow” these cells give off, and doctors examine the picture to spot tumors.

The results of the study were presented the first week of September at the American Society of Clinical Oncology’s 2008 Breast Cancer Symposium in Washington, D.C. A follow-up clinical study comparing MBI to MRI is next; these results should be interesting, as MBI is more expensive than mammography, yet only one-fifth the cost of breast MRI.

But an MBI is not necessarily for every woman. Rather than replace mammograms for women at average risk for cancer, MBIs might become an additional tool for higher-risk women with a lot of dense tissue that makes tumors hard to spot on mammograms and at a lower cost than MRI (about one-fourth of women 40 and older have dense breasts). With an aging population, this translates to a larger market of higher-risk women, thereby making the availability of MBI an attractive option for a hospital or clinic.

Cost of Improving Detection

Cost, of course, is always an issue. More advanced, digital systems can cost nearly five times that of an existing system, and without ample data from multiple studies and rather limited success stories, buyers may be reluctant to make a spend. This is certainly true for private radiology practices that need to manage costs very tightly.

It is costly for manufacturers too. GE Healthcare or Siemens Medical Solutions would only consider producing such systems if a sizeable enough market could exist. Adoption of MBI monitors perhaps might be slow at the beginning, but as hospitals rush to purchase state-of-the-art equipment, GE and Siemens could eventually realize profit. Additionally, manufacturers can harness the power of their education, training and support communities to drive incremental revenues from training hospital personnel – perhaps staff mammographers or sonographers – in the use of the MBI system.


This article appeared in Imaging Technology News, November/December 2008 Issue