MRI Contrast Agent Illuminates Aggressive Breast Tumors

Gadolinium-containing imaging agent could improve breast cancer survival.

Many patients rely on magnetic resonance imaging (MRI) for breast cancer diagnosis. Unfortunately, current methods may not be completely accurate for all patients.

An investigational MRI contrast agent has shown promise in identifying early-stage breast cancer, while also distinguishing between aggressive and slow-growing cancers, according to a study published by Nature Communications. This investigational gadolinium-based agent may provide significant benefits over current agents, according to the study authors.

“Doing both will help doctors find the right treatment,” said lead researcher Zheng-Rong Lu, PhD. “There’s no such technology available now that we know of.”

The contrast agent contains gadolinium and is safer than current methods, according to the authors. The investigational agent requires a dose that is 20 times smaller than traditional methods, allowing it to easily leave the body.

Even at low doses, the authors found that the agent illuminates biomarkers and overcomes the challenge of the low-sensitivity of MRIs, according to the study.

In the study, the authors combined tri-gadolinium nitride metallofullerene (Gd3N@C80) with a novel peptide called ZD2. The authors report that gadolinium ions are encaged in a hollow molecule in Gd3N@C80, which is different than the traditional agent.

“The cage prevents direct contact between the gadolinium and tissue, and the gadolinium will not be released, which prevents any kind of interaction with tissue,” Dr Lu said. “But the key technology for our targeted contrast agent is the peptide attached.”

The investigators then applied the peptide to the surface of the molecule. ZD2 targets the extradomain-B fibronectin (EDB-FN), which is expressed in the area around cancer cells. The peptide has been linked to tumor invasion, metastasis, and drug-resistance, according to the study.

In mouse models, the novel contrast agent was able to detect breast cancer. Notably, the signal created for 3 aggressive triple-negative breast cancers were brighter, according to the study.

Since slow-moving breast cancers secrete less EDB-FN, a smaller amount of contrast agent attached, resulting in a more muted effect compared with aggressive tumors, according to the authors.

These findings suggest that the investigational contrast agent can effectively detect breast cancer, but can also distinguish tumor type, according to the authors.

If proven in humans, the novel contrast agent may be able to better inform treatment decisions and improve survival rates among patients with breast cancer.

The authors are currently looking for a way to lower the production cost of the agent to ensure that it could be implemented in a clinical setting, the study concluded.