Liver cancer is one of the deadliest forms of cancer, claiming about 700,000 lives every year worldwide. The most common type of liver cancer, hepatocellular carcinoma, is often treated with a complex and invasive procedure called transarterial chemoembolization (TACE), which involves injecting chemotherapy drugs and blocking the blood supply to the tumor using microcatheters guided by X-rays.
However, this method has several limitations, such as the risk of damaging healthy cells, the difficulty of visualizing the tumor on X-rays, and the need for highly skilled personnel. Moreover, TACE may not be effective for tumors that are located higher than the injection site, as the force of gravity prevents the drugs from reaching them.
But what if there was a better way to deliver treatment to liver tumors, using tiny robots that can navigate through the blood vessels and target the tumor with precision and accuracy?
This is the idea behind a novel approach developed by Canadian researchers, led by Dr. Gilles Soulez, a radiologist from Montreal. The researchers have created magnet-guided microrobots, made of iron oxide nanoparticles, that can be controlled by an external magnetic field inside a Magnetic Resonance Imaging (MRI) device.
The MRI device not only provides a high-resolution image of the tumor, but also generates a magnetic field that can steer the microrobots to the desired location. The researchers have also developed an algorithm that combines the magnetic force with gravity, making it easier for the microrobots to travel to the arterial branches that feed the tumor.
The microrobots are injected into the body using an implantable catheter, similar to those used in chemotherapy. The microrobots form “particle trains”, which have a greater magnetic force and are easier to pilot and detect on the MRI images. The microrobots can then deliver drugs or other agents to the tumor site, while sparing the healthy cells.
The researchers have tested their approach on 12 pigs and 19 patients who had undergone TACE, and found promising results. The microrobots were able to reach the tumor site in over 95% of cases, and showed no adverse effects on the animals or the patients.
The researchers believe that their method could improve the outcomes and quality of life of liver cancer patients, as well as reduce the costs and risks associated with TACE. They also hope that their method could be applied to other types of cancers and diseases in the future.
The following table summarizes the main differences between TACE and the magnetic microrobot approach:
| Method | TACE | Magnetic microrobots |
|---|---|---|
| Image guidance | X-ray | MRI |
| Navigation force | Gravity | Magnetic field + gravity |
| Injection device | Microcatheter | Implantable catheter |
| Drug delivery | Embolization | Particle trains |
| Advantages | Established technique | Better visualization, accuracy, and safety |
