AIDER Collaboration Project

WTSH Online Editorial Team: Prof. Rafecas, why are international collaborations such as those in the AIDER project so crucial – both in general and specifically for medical imaging?

Prof. Magdalena Rafecas: International collaborations are – particularly in a project like AIDER – crucial because these are highly complex undertakings that can rarely be tackled by a single research group on its own. Medical imaging, or more specifically nuclear imaging, is also a highly interdisciplinary field: it requires expertise in radiation physics, electronics, image reconstruction algorithms, software development, as well as continuous feedback from clinical practice. No single institute can provide all these areas of expertise to the necessary depth. Europe is now a key hub for many international experts in these fields. AIDER brings us together and creates a shared platform to pool our knowledge and develop solutions that no single partner could achieve on their own.

WTSH Online Editorial Team: What does the new technology you and your partners are working on actually mean for patients? How might it improve future cancer treatments?

Prof. Magdalena Rafecas: The aim is to develop an imaging method specifically for verifying different radionuclide therapies (also known as image-based verification or dosimetry verification). To explain: Radionuclide therapy is a targeted nuclear medicine treatment in which radioactive substances are bound directly to diseased tissue to destroy tumour cells from within. By using imaging techniques, we aim to verify whether an administered therapeutic radiopharmaceutical actually reaches the intended site in the body, accumulates there, and acts exactly as planned. The point is that every patient absorbs the radiopharmaceutical differently. Without imaging, treatment would be carried out ‘blindly’. The aim is for critical organs to absorb as little of the radiopharmaceutical as possible, whilst ensuring that the tumour has been sufficiently irradiated. Imaging helps us to optimise subsequent treatment cycles. For example, it shows whether a tumour received too little radiation in a previous cycle. We can then increase the next dose of the radiopharmaceutical accordingly. Conversely, we can also see if a sensitive organ is already close to its permissible exposure limit. In this case, we reduce the next dose to ensure the patient’s safety. Furthermore, the images provide clues as to how quickly a patient metabolises the radiopharmaceutical. If metabolism is particularly rapid, the next treatment cycle may be able to take place sooner.

WTSH Online Editorial Team: Does that mean this image-guided verification turns every treatment cycle into a learning step? 

Prof. Magdalena Rafecas: Exactly. You can see how well the therapy is actually working and how resilient the body is – and adjust the subsequent cycles so that they become more effective and safer. To continue the comparison with the film mentioned above: our miniature submarines – the radiopharmaceuticals – are equipped with ‘weapons’ and ‘transmitters’. The weapon has a short range but great penetrating power, for example the alpha radiation in Targeted Alpha Therapy (TAT). The radiopharmaceuticals also emit gamma rays, which are detected by the Compton camera; the Compton camera is therefore the ‘radio receiver’ that allows us to locate the radiopharmaceuticals.

WTSH Online Editorial Team: Looking at the project: What strengths does your Lübeck team bring to this European network, and what do you benefit from most in return?

Prof. Magdalena Rafecas: We deal with what is known as “image reconstruction”, which means we bridge the gap between the measuring instruments and the image. We are like tailors who tailor a bespoke suit for the camera to extract the best possible image from the available data. This “bespoke suit” consists of physical models and algorithms. My team and I have extensive experience in crafting such “suits” for new prototypes in nuclear medicine imaging, for which there is no plug-and-play software. A project like AIDER is a win-win situation. Although my team also works on the development of specialised imaging devices – for example, we are developing the world’s first PET scanner for zebrafish – we do not have the resources to develop Compton cameras. It is therefore essential to collaborate with experts in this field. Such collaboration also offers us the opportunity to explore novel and promising therapies, such as Targeted Alpha Therapy (TAT). As far as I am aware, there is currently no independent TAT research being conducted in Schleswig-Holstein. Globally, it remains predominantly in the research phase and is only used at specialised centres, such as the AIDER partner in Lyon.

The interview was conducted by Ute Leinigen