"This is the first major advance in breast imaging and breast cancer screening since the development of breast MRI," said lead researcher Elizabeth A. Rafferty, M.D., director of Breast Imaging at the Avon Comprehensive Breast Center at Massachusetts General Hospital in Boston. "The beauty of tomosynthesis is that it addresses two major concerns with screening mammography: missed cancers and false positive rates."
According to the National Cancer Institute, there is convincing evidence that screening mammography reduces breast cancer mortality in women between the ages of 40 and 74. However, as many as 30 percent of breast cancers are not detected by mammography and an additional eight to 10 percent of women who undergo a screening mammogram are recalled for further testing when no cancer is present (called a false positive result).
Unlike a screening digital mammogram, which involves two X-ray images of each breast, breast tomosynthesis captures multiple, low-dose images from different angles around the breast. The images are then used to produce a three-dimensional reconstruction of the breast. Both digital mammography and breast tomosynthesis, which was approved by the United States Food and Drug Administration (FDA) in February of 2011, can be performed on the same mammography equipment in rapid succession.
Dr. Rafferty's study involved 1,192 women recruited from five sites, of whom 997, including 780 screening cases and 217 women who needed pre-biopsy breast imaging, had complete data sets. Each of the women underwent a standard digital mammogram followed by breast tomosynthesis. The total radiation dose for the combined procedure was less than 3 milligray, which is the FDA limit for a single mammogram.
Drawing from the eligible cases, the researchers then conducted two reader studies involving 312 and 310 cases, respectively. Twelve radiologists participated in the first reader study; 15 radiologists in the second. A total of 48 cancers were included in the first reader study; 51 cancers in the second.
Compared to digital mammography alone, the use of both standard mammogram and tomosynthesis resulted in increased diagnostic accuracy for all 27 radiologists. Additionally, the diagnostic sensitivity of the combined exam — or the rate at which cancer present in the breast was correctly identified — increased by 10.7 percent for radiologists in Reader Study 1 and 16 percent for radiologists in Reader Study 2.
"Almost all of the gains in diagnostic sensitivity with the combined modality were attributable to the improved detection and characterization of invasive cancers, which are the cancers we are most concerned about because of their potential to metastasize," Dr. Rafferty said.
With the addition of breast tomosynthesis to standard digital mammography, false positive recall rates also significantly decreased for all 27 of the radiologists. Absolute recall rate reductions of 38.6 percent and 17.1 percent were seen in Reader Studies 1 and 2, respectively.
"In the clinical setting, we would expect that type of reduction in recall rate to translate into a substantial number of unnecessary diagnostic tests being avoided," Dr. Rafferty said.
"Assessing Radiologist Performance Using Combined Digital Mammography and Breast Tomosynthesis Compared to Digital Mammography Alone: Results of a Multicenter, Multireader Trial." Collaborating with Dr. Rafferty were Jeong Mi Park, M.D., Liane E. Philpotts, M.D., Steven P. Poplack, M.D., Jules H. Sumkin, M.D., Elkan F. Halpern, Ph.D., and Loren T. Niklason, Ph.D.
Radiology is edited by Herbert Y. Kressel, M.D., Harvard Medical School, Boston, Mass., and owned and published by the Radiological Society of North America, Inc.
RSNA is an association of more than 50,000 radiologists, radiation oncologists, medical physicists and related scientists, promoting excellence in patient care and health care delivery through education, research and technologic innovation. The Society is based in Oak Brook, Ill.
For patient-friendly information on breast imaging, visit RadiologyInfo.org
Fraunhofer ITEM takes over and continues development of inhalation technology assets from Takeda
10.02.2016 | Fraunhofer Institute for Toxicology and Experimental Medicine
Laser-assisted wound closure for oral and maxillofacial surgery
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Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock which attains an accuracy which had only been predicted theoretically so far. Their optical ytterbium clock achieved a relative systematic measurement uncertainty of 3 E-18. The results have been published in the current issue of the scientific journal "Physical Review Letters".
Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock...
The University of Würzburg has two new space projects in the pipeline which are concerned with the observation of planets and autonomous fault correction aboard satellites. The German Federal Ministry of Economic Affairs and Energy funds the projects with around 1.6 million euros.
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Physicists from Saarland University and the ESPCI in Paris have shown how liquids on solid surfaces can be made to slide over the surface a bit like a bobsleigh on ice. The key is to apply a coating at the boundary between the liquid and the surface that induces the liquid to slip. This results in an increase in the average flow velocity of the liquid and its throughput. This was demonstrated by studying the behaviour of droplets on surfaces with different coatings as they evolved into the equilibrium state. The results could prove useful in optimizing industrial processes, such as the extrusion of plastics.
The study has been published in the respected academic journal PNAS (Proceedings of the National Academy of Sciences of the United States of America).
Exceeding critical temperature limits in the Southern Ocean may cause the collapse of ice sheets and a sharp rise in sea levels
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Indications of light-induced lossless electricity transmission in fullerenes contribute to the search for superconducting materials for practical applications.
Superconductors have long been confined to niche applications, due to the fact that the highest temperature at which even the best of these materials becomes...
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