Impedance Scanning Evaluated as Alternative to Mammograms

Whether a painless, portable device that uses electrical current instead of X-rays to detect breast cancer could be an alternative to conventional mammograms is being evaluated.

The Medical College of Georgia (Augusta, GA, USA) is one of 20 centers internationally studying new technology developed by Z-Tech, Inc. (Westford, MA, USA), to compare traditional mammograms with impedance scanning, a technique based on evidence that electrical current passes through cancerous tissue differently than through normal tissue.

This phase of the study will focus on women age 40-50. Older women have less dense breast tissue so a tumor is easier to find, according to Dr. James Craft, MCG radiologist and principal investigator on the study. Mammograms, also performed in the study, are more accurate in this population; therefore, this phase will be a more comprehensive test of the new technology, according to Dr. Craft. The first phase of the study, which began in 2005, was open to women of all ages.

"Normal breast tissue is very dense, especially in younger women, and can hide tumors,” Dr. Craft noted. "While we've known for a while that water flows more freely through cancerous cells, we also know that electrical current flows easier through cancerous and tumor tissue.”

The Z-Tech scan works by placing a flower-shaped grouping of electrodes over each breast and sending a small, painless amount of electricity through them. Unlike conventional mammography, the scan does not involve breast compression or radiation. "It's like doing an EKG [electrocardiogram] of the breast,” Dr. Craft commented.

A computer immediately calculates and presents a report based on the electrical signature of the breast tissue. Rather than waiting on breast image from a traditional mammogram, the computer immediately notes whether the scan is positive or negative for cancer. However, for study purposes, neither Dr. Craft nor the patient will know the results. Patients must undergo a mammogram within 90 days, which Dr. Craft interprets. Z-Tech compares those results to the electrical study.

The hope is that the new test--called HEDA (homologous electrical difference analysis)--will provide an alternative to mammograms. While Dr. Craft believes that having this test should help find more tumors, he does not think it will replace conventional mammography. "This method doesn't use radiation, is portable, and there is no pain associated with the squeezing that mammograms require,” he stated. "I can see it being used as an additional test. I don't think it will replace mammography, but it could increase our chances of catching breast cancer.”

Related Links:
Medical College of Georgia
Z-Tech