Radar breast imaging passes first clinical test

Prototype promises safe, quick assessments

In its first real-world test, a radar-based imaging technology uncovered a malignancy that couldn't be detected with conventional x-ray mammography. The technology, which was tested only on women with known breast cancer, identified a tumor in a woman who felt a lump three months after a normal routine screening mammogram, reports Dr. Allan Malmed, medical director of Northwest Community Hospital's Interdisciplinary Breast Center in Arlington Heights, IL.

"We put her in the machine and sure enough, the device was able to detect the tumor that mammography couldn't, even when we went over the mammogram with a fine-tooth comb," he said. "There was just no indication anywhere of a suspicious abnormality."

Malmed acknowledges that the findings from his initial experience with radar mammography come early in the life of the technology; there are no data to indicate how sensitive and specific it will turn out to be. But he has evaluated 21 other women with known breast cancer and found that radar is quick (the procedure takes only five to 10 minutes), comfortable (it requires no breast compression), and convenient. Scanning is done from below a padded table on which the patient lies face down.

Radar mammography also appears to be safe. The technology uses low-energy radio waves rather than ionizing radiation, such as x-rays. Radar scans of structures high in water content, such as tumors and cysts, produce different signals from those of normal tissue. According to Denis E. Jones II, president and CEO of Interstitial, the Mount Prospect, IL company, that is developing the technology, the signal strength of the radar that bounces back from a tumor or a cyst is significantly stronger than the one coming from normal tissue. Preliminary results indicate that radar mammography generates a strong signal-to-noise ratio leading to clear 3D images of malignant subtleties that may not be apparent when using conventional mammography, he said.

It is too soon to tell whether this technology will succeed as a stand-alone imaging modality. But both Jones and Malmed believe that it may complement conventional scanning in much the same way as other mammography adjuncts, such as MR and ultrasound. Radar mammography may be particularly useful when imaging women with dense breast tissue.

As Malmed explains, MR is probably the best technique for imaging dense breasts, but it takes an hour, may require contrast administration, and is expensive. Ultrasound, while relatively fast and low-cost, depends on the skill of the operator.

"This has the potential to be right up there with MRI but not nearly as expensive," Malmed said. "It could be a 10-minute thing."

Interstitial is fine-tuning its prototype device in preparation for planned clinical trials of the technique. The initial instrument used by Malmed was operated manually to image only those portions of the breast that harbored known malignancies. The next version will be automated to produce more consistent and reliable scans of the entire breast, Jones said.

"While we do not have a statistical basis for a claim (that radar mammography is an effective breast imaging vehicle), we have sufficient information to warrant our belief that the technology is more than a curiosity," he said. "The challenge for our technology is to be sure it does not copycat mammography but adds some real value beyond what mammography provides."