For many women, regular mammograms allow physicians to spot breast cancer tumors as dense lumps in the breast. But mammography often fails in women who have dense breast tissue due, for instance, to genetics or scarring. According to Eric Rosen, M.D., a Duke University Medical Center physician and lead author on the study, "In women with dense breasts, it's very hard to pick out even large anatomic abnormalities."
Stan Majewski, Jefferson Lab Detector Group Leader and principal investigator on the instrumentation part of the project, led the team that designed and built the PEM unit. He says PEM imaging works differently than mammography. It reveals breast tissue that is showing higher metabolism than other areas. "The imager we built is a functional imager. That is, it indicates something about physiology, which can be different from anatomy," he says.
To fuel rapid growth, cancer cells use more glucose (sugar) than surrounding cells. In this imaging procedure, a small dose of radioactive molecules that look like sugar, called fluorodeoxyglucose (FDG), are injected into the body, where they're absorbed by cancerous tumors. The PEM device pinpoints tumors in the breast by detecting the location of FDG uptake. "By detecting areas that have increased glucose metabolism, you can often distinguish a cancer between normal surrounding tissue, which in general has low uptake of FDG," Dr. Rosen says.
For the study, Duke physicians recruited patients with suspicious mammograms who were scheduled for bio