In 2020, breast cancer was the most commonly diagnosed form of cancer worldwide, with more than two million cases. In women, this particular type of cancer accounts for 25% of all cancer cases and is responsible for 15.5% of all cancer deaths. Early confirmation of the diagnosis is crucial as it allows prompt initiation of appropriate treatment, thereby significantly improving the chances of survival. Because of its importance, researchers worldwide are working diligently to improve early detection methods for this condition.
And this has now been achieved by a team of researchers from the Paul Scherer Institute PSI and ETH Zurich together with the Baden Cantonal Hospital (KSB) and the University Hospital Zurich (USZ). Researchers have achieved a significant breakthrough in early tumor detection, significantly improving existing techniques. The improved method now provides more reliable results and is much less painful for patients. Additionally, conventional computed tomography (CT) has been upgraded to substantially increase image resolution without increasing radiation dose. This development marks a major milestone in medical imaging and promises to revolutionize tumor detection and the patient experience.
This means that small calcium deposits known as microcalcifications, which indicate breast cancer, can potentially be detected earlier than before. As a result, the chances of successful recovery for affected women are significantly increased. The technique, which is based on X-ray phase contrast, could quickly be used in clinical settings, according to experts. "We still need some time, but we have reached a milestone with our work," says Marco Stempanoni, head of the research group at PSI and professor of X-ray imaging at ETH Zurich.
How effective is mammography?
Increasing the accuracy of early tumor detection plays an important role in the fight against breast cancer. Currently, many industrialized countries rely on mammography screening programs as an early detection method. Nevertheless, the effectiveness of mammography screening remains a subject of controversy.
Controlled studies have shown that only 46% of suspected cases detected during screening are confirmed to be true cancer cases. This highlights the need for further development in detection techniques to improve accuracy and reduce false positives. A false alarm can cause great anxiety for victims, as biopsy results can take two to three weeks to become clear. Additionally, studies show that mammography misses 22 percent of true cases, lulling victims into a false sense of security. This is even more serious, as it means valuable time is lost before treatment can begin.
The weaknesses cited here stem from the challenges that even experts face when interpreting mammography images. Soft breast tissue presents only limited contrast on X-ray, while the complex interior of the breast is often obscured on two-dimensional fluoroscopy. To take a breast X-ray, it must be squeezed firmly to keep it still. Patients sometimes find it uncomfortable or painful, which is why some women don't go for screening.
Three-dimensional X-rays bring advantages
Unlike three-dimensional X-ray staging, researchers enhance tumor diagnosis with additional anatomical information. In other words, the images they produce capture information that is not taken into account in conventional X-ray imaging: the signals produced when biological tissue refracts and scatters radiation. As X-rays pass through structures of different densities, they undergo not only attenuation but also refraction and diffraction. This information brings benefits to improving both the contrast of the images and their resolution.
