Can we improve cancer detection in mammography?
Digitization of the imaging procedure was a great leap forward, particularly in terms of workflow and dose efficiency. Although screening programs are proven to decrease breast cancer mortality by up to 45%, we still miss 30% of cancers. Also, high recall rates are a frequent source of debate. In short, there is still room for improvement in both sensitivity and specificity.
Photon counting with its high DQE and scatter rejection has shown improvements in dose efficiency. In other words, higher diagnostic image quality at a lower dose. In addition to this, several new technologies with potential for improved cancer detection are now emerging.
Digital breast tomosynthesis has been a source of “buzz” in the field of mammography for half a decade. The problem this technology solves is the overlapping of tissue, meaning glandular tissue that could potentially hide cancers, a problem that doctors face in normal 2D projection mammography.
However, the diagnostic imaging industry has yet to prove the clinical value of tomosynthesis, and so far, there are no diagnostic protocols for how to use the technology. The questions in need of answers are: Should tomosynthesis be used together with 2D? If so, for which cases? How will this fit into a screening workflow and how will the radiologists – in scarcity in most countries – deal with 20 to 30 times the number of images?
Several vendors are in the research phase when it comes to tomosynthesis, and a few also have commercially available systems – but opinions on the benefits and clinical use differ.
Photon counting using a scanning detector shows great promise for this type of 3D image acquisition, since tomosynthesis in itself is a scanning technology and hence a scanning system will not have to deal with the potential motion and ghosting artifacts and higher dose associated with flat panel digital systems.
Spectral imaging is another technology currently under trial. With the use of photon counting, multiple-energy images can for the first time be acquired through a single exposure, thanks to the possibility to set multiple energy thresholds in the photon counting detector. In practice, this means that material decomposition of the breast can be achieved: malignant tissue can be separated from normal tissue through image subtraction thanks to the different compositions of the tissues. Single-shot spectral imaging shows promise as both a screening and diagnostic tool. Used without contrast agent, it is as quick as a normal screening exam, but offers the potential for higher sensitivity and specificity. With contrast, it may be a faster, more cost-efficient alternative to MRI.
If you are attending ECR 2010 in Vienna, there is an excellent opportunity to catch up on the latest developments in these technologies. During a symposium on March 6, prominent experts from four different countries will share their views on the challenges of early cancer detection and how new technology can improve cancer visibility while significantly lowering dose.
Speakers at the symposium are:
- Martin Yaffe, Professor, Toronto, Canada
- Matthew Wallis, Consultant Radiologist, Addenbrooke’s Hospital, Cambridge, UK
- Felix Diekmann, MD, Charité Hospital, Berlin, Germany
- Jean-Charles Piguet, MD, Imagerive, Geneva, Switzerland
Time and place: March 6, 2:00 p.m. to 3:30 p.m., course room N/O, level 01
Book your seat at: ecrsymposium@sectra.com
Further reading:
- Why low dose really matters in screening mammography, by Dr Jean-Charles Piguet, ImageRive, Geneva, Switzerland
- Mammography shifts toward spectral imaging, by Mats Danielsson, Professor, Royal Institute of Technology (KTH) in Stockholm
On September 1, 2011, Philips acquired the MicroDose operations from Sectra and hence all questions regarding photon-counting, low-dose mammography, MicroDose etc are referred to Philips. For more information on MicroDose Mammography or on the acquisition please go to www.philips.com/microdose
