Worldwide, about 1.5 million people develop liver cancer every year. If patients do not benefit from surgery or chemotherapy, then radioembolization is a treatment option. This is a technique that uses a catheter to administer small radioactive beads that flow through the hepatic artery to the tumor in the liver. There they get stuck in the capillaries, causing the liver tumor to be irradiated from within. Radio embolization is therefore also called selective internal radiotherapy (SIRT).
The effect of radio embolization strongly depends on where exactly the globules end up in the liver. Where do you allow the globules to flow into the hepatic artery, how quickly should you administer them, how do they divide?
“We see divergent results with radio embolization, which probably mainly have to do with the eventual distribution of the spheres in and around the tumor,” says Frank Nijsen of the Radboudumc Imaging Department and coordinator of the project. “With this research we want to gain a better understanding of the factors that influence the ultimate distribution of the globules in the liver. If we can influence the distribution, it will be possible to irradiate the tumor tissue more specifically and to save the healthy liver tissue. If we can indeed predict this after the completion of this study, then we expect fewer side effects for patients and more often a long-term stop of the growth or even a reduction in their tumors. ”
Make treatment visible
Radio-embolization mainly uses radioactive yttrium and holmium spheres. The latter were developed by Quirem Medical, which as a company is also involved in the project, as are the companies Terumo, Organ Assist, Femto and Siemens Healthineers. A big advantage of the holmium spheres is that they – in contrast to yttrium – can be seen very well on MRI, CT and SPECT images. Especially with MRI we can very accurately measure and analyze the distribution in the liver very accurately at high resolution. Nijsen: “This project fits perfectly within the research we are conducting at Radboudumc into image-guided radionuclide interventions and improving the techniques in order to achieve the best results for the patient.”
Reliable computer model
The research program includes fundamental and experimental as well as patient-related research. “We use experimental setups, phantoms, animal livers left over after slaughter, and non-usable human livers that become available around the liver donation process and after liver transplantation,” says Nijsen. “All the knowledge we acquire in this way should ultimately result in a computer model. This computer model will be able to predict, based on the vascular system of a patient, where the catheter should be placed, and with how many beads the most optimal treatment – a lot of activity in the tumor and minimal activity in the healthy liver tissue – can be given. ”
The research into optimal treatment will eventually be concluded with the actual treatment of patients in the special MITeC operating room at Radboudumc. Nijsen: “We will then test whether our computer model indeed delivers better patient treatment. For example, a validated, generally applicable treatment method should follow from this research, with the aim of better and more consistent results in radio embolization. ”