Breast Cancer Detection 2.0

Breast cancer detected with nanoprobes and SQUID

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) While mammograms are the only clinically proven method of detecting breast cancer, they are far from fool-proof.  New technology currently being studied may offer better, more accurate assessments.

Researchers have combined teeny tiny magnetic probes and what's called superconducting quantum interference device (SQUID) sensors to pinpoint never-before-visible breast cancer cells. This experimental technique is 100 times more sensitive than mammography and up to a thousand times better than a physical exam.

"Your genetic make-up impacts breast cancer risks."

While mammography detects quite small breast cancers, it also misses between 10-25 percent of tumors and can't tell whether or not the spots are actually cancerous.

A research team from the University of New Mexico School of Medicine and Cancer Research and Treatment Center, Senior Scientific, LLC, and the Center for Integrated Nanotechnologies facility at Sandia National Laboratories have been testing a new technique that combines imaging with diagnostic information.

The method created nanoprobes by attaching iron-oxide magnetic particles to antibodies (immune system's response to antigens - invaders) against HER-2 proteins. HER-2 is over-expressed (there's too much of it) in about 30 percent of breast cancers.

Daniel B. Kopans, M.D., Professor of Radiology at Harvard Medical School, explains in an email to dailyRx, "The investigators are using a novel way to essentially tag an antibody, with a material that can be found (imaged) when it sticks to the antigens on the surface of cells. This approach has been tried for years with radioactive tracers without much success."

Dr. Kopans continues, "They are using magnetic technology to try to accomplish the same thing and I would wonder if the ability to track the magnetic particles is better or worse than if the antibodies were labeled with radioactive material.

The experimental system being tested was able to  distinguish cells with and without the HER-2 protein and identify it in biopsied tissue from mice.

Using a synthetic breast to determine how sensitive the system was, Dr. Helen Hathaway, a biomedical researcher at the University of New Mexico says the technique was 100 times more accurate in detecting cancer cells than mammography. She explained the method found lesions that had "about 1000x fewer cells than the size at which a tumor can be felt in the breast.

Dr. Kopans believes the technology warrants further study, "but there are lots of hurdles ahead," he says. "Even if this works it will be limited to these cancers. The question is can they get enough of a concentration of their nanoparticles to stick to the tumor to be able to distinguish them from the particles that will stick to normal breast tissue and be simply circulating in the blood (this is called "signal to background")," Dr. Kopans said.

Authors conclude that the system needs further refinement to allow for the tumor to be not only seen but also classified in terms of protein expression. This could bypass the need for biopsies, predict disease progression potential and be useful in creating individualized treatment plans that could improve survival.

"There are a lot of "ifs" here. I think it is a novel approach, but I am not optimistic that it will be able to detect the small cancers, that they suggest, deep in the breast," Dr. Kopans said.

This study was published in the journal Breast Cancer Research.

Reviewed by: 
Review Date: 
November 4, 2011
Last Updated:
November 7, 2011