Scientists at Rutgers University-New Brunswick have invented a groundbreaking method to detect tiny cancerous tumors and track their spread. The method uses infrared light-emitting nanoparticles that can detect the presence of micrometastases months before they grow big enough to be able to detect by traditional imaging techniques.

Micrometastases are a small number of cancer cells that have been separated from the primary tumor to spread to other areas of the body. Micro-metastatic cells are too few to be detected by CT imaging, MRI or PET scans, and currently there are no chemo therapeutic agents specifically tailored to combat micro-metastases. But this new imaging technique holds new promise.

“We’ve always had this dream that we can track the progression of cancer in real-time, and that’s what we’ve done here,” explains Prabhas V. Moghe, a corresponding author of the study. “We’ve tracked the disease in its very incipient stages.”

One of the major challenges in cancer diagnosis today is the ability to detect early tumors before they metastasize, and most imaging methods fail to do so. But this study shows that one the nanoprobes – microscopic optical devices that emit short-wave infrared light – are injected, they travel through the bloodstream and detect tiny tumors and even tracking them in multiple organs.

Nanoparticles Detect Cancer Months Before It Can Be Done By Conventional Imaging Techniques. Image shows human breast cancer cells in a mouse model were “chased” with novel rare earth nanoscale probes injected intravenously.  [Credit: Harini Kantamneni and Professor Prabhas Moghe/Rutgers University New Brunswick]

“The Achilles’ heel of surgical management for cancer is the presence of micrometastases,” says Dr. Steven K. Libutti, director of Rutgers Cancer Institute of New Jersey. “This is also a problem for proper staging or treatment planning. The nanoprobes described in this paper will go a long way to solving these problems”

In their earlier experiment in mice, the nanoprobes were shown to perform significantly “faster” than MRIs and accurately “detect” the minute spread of tiny lesions and tumors in the adrenal glands and bones of the animals. In humans, this would likely translate to cancer detections months earlier, potentially improving cure rates and survival times.

“Cancer cells can lodge in different niches in the body, and the probe follows the spreading cells wherever they go,” explains Vidya Ganapathy, a corresponding author and assistant research professor. “You can treat the tumors intelligently because now you know the address of the cancer.”

Another promising application for nanoprobes in the future is in surgery. Not only can they be used to mark tissues that surgeons want to remove, but also to track the effectiveness of immunotherapy, which includes stimulating the immune system to fight cancer cells. Researchers say their technology could detect and track the 100-plus types of cancer, and could be available in less than five years.

The study, entitled “Surveillance nanotechnology for multi-organ cancer metastases” has been published in the journal Nature Biomedical Engineering. [ePDF]