MRI combines with sound waves to reveal the stiffness of tumors
Getting drugs into the tumors of a cancer patient can be a tricky business. One of the many obstacles clinicians have to contend with centers on the density and stiffness of the tumor itself, which can impact how well the drugs are able to infiltrate the growth. A new imaging technique could provide them with a guiding light, however, by revealing which ones need to be softened up ahead of time.
The research was led by scientists at London’s Institute of Cancer Research (ICR) and makes use of an imaging technology called magnetic resonance elastography (MRE). This is much like a traditional MRI, except that it brings sound waves into the mix to paint a clearer picture of body tissue composition.
Still a non-invasive technique, MRE sees a small pad placed on the patient’s skin which sends sound waves through the body while measuring how fast they travel. Stiffer tissues make for faster travel times, with MRE exams already in use as a way of tracking the progression of liver disease as the organ hardens.
But its potential doesn’t end there. Scientists have also been exploring how MRE could be used to investigate the stiffness of tumors, with the ICR team among them. Specifically, the team applied the technique to tumors in mice, looking to see how much of a role collagen, the structural protein in connective tissues, muscles, bones and skin, plays in their structure and density.
Through their experiments, the team was able tease out some useful insights around the density of different tumor types, and how they might be able to destroy them more effectively. The research revealed that collagen plays an important role in the stiffness of breast and pancreatic cancers, while others, such as brain tumors, were found to be far softer.
And with this new understanding of the tumors comes new options to attack them. The team administered collagenase, which is a drug that breaks down the bonds in collagen and therefore the stiff matrix that serves as a foundation for these tumors to grow. Continued MRE monitoring of the tumors indeed found that elasticity and viscosity of mouse breast tumors were reduced by around 20 percent.
“Our research shows that this new type of scan can give valuable diagnostic information about breast and pancreatic tumors non-invasively by assessing their stiffness,” says study co-leader Dr Simon Robinson. “If confirmed in a clinical trial, we could use this technique to identify patients most likely to benefit from treatments that target the dense scaffold upon which these tumors grow. It gives us a new way of looking at cancers, and a potential way to monitor new treatments that alleviate tumor stiffness in order to help enhance the efficient delivery and uptake of chemotherapy.”
The research was published in the journal Cancer Research.
Source: Institute of Cancer Research