A new magnetic resonance imaging (MRI) contrast agent has been developed by Case Western Reserve University (CWRU) scientists that can detect smaller aggressive breast cancer tumours and micrometastases.

The small peptide gadolinium-based MRI contrast agent works by binding to molecular markers, called fibrin-fibronectin complexes, which are expressed in high-risk primary tumours and metastases.

Called CERKA, the small peptide is a chain of five amino acids, and does not adhere to healthy tissues.

However, researchers found more fibronectin is expressed in metastatic tumours and aggressive primary tumours, especially those preparing to metastasize, and more image contrast is generated.

"We not only detect the tumour, but detect its aggressiveness."

Case Western Reserve University biomedical engineering professor Zheng-Rong Lu said: "Currently, there is no imaging technology in clinical use that can detect tumours or metastases smaller than 2mm in diameter.

"This can detect them as small as 300 microns, a few hundred cells. We not only detect the tumour, but detect its aggressiveness."

During testing on mice with breast cancer metastases, signals generated during a molecular MRI highlighted the agent was effective at delineating primary tumours and micrometastases in the lung, liver, lymph node, adrenal gland, bone and brain as small as 300 micrometers.

The agent was said to have increased signal output from metastases by 77% to 122%. The findings were confirmed using Wilson ‘s high-resolution fluorescence cryo-imaging system.

The scientists intend to undertake tests that will confirm safety of the test, with an aim to initiate clinical trials within the next three years.

A previous biodistribution test showed the agent clears the body in eight hours, which is the same time as existing clinical contrast agents.

In addition, the researchers are working to make the agent more tumour-specific, starting with configuring the technology to detect prostate cancer.

Metastasis is the most common cause of breast cancer deaths. The early detection and treatment of primary and metastatic tumours is said to increase the chances of survival.